摘要：报道了基于梯度能带结构的高速室温中波红外HgCdTe器件,器件设计为n-on-p同质结结构,在300 K的零偏压条件下达到了1.33 ns(750 MHz)的总的响应时间,相对于非制冷的碲镉汞器件和工作于高偏压下的碲镉汞APD器件响应速度有所提高。基于一维模型的分析表明,吸收层中的组分梯度可以形成内置电场并改变了载流子的输运特性,该模型由不同组分梯度的HgCdTe器件的实验对比验证。因此,此项工作优化了高速HgCdTe中波红外探测器的设计,并为设计超快中波红外光电探测器提供了一种可行的思路。

摘要：Target detection in low light background is one of the main tasks of night patrol robots for airport ***,if some algorithms can run on a robot platform with limited computing resources,it is difficult for these algorithms to ensure the detection accuracy of human body in the airport terminal. A novel thermal infrared salient human detection model combined with thermal features called TFSHD is proposed. The TFSHD model is still based on U-Net,but the decoder module structure and model lightweight have been redesigned. In order to improve the detection accuracy of the algorithm in complex scenes,a fusion module composed of thermal branch and saliency branch is added to the decoder of the TFSHD model. Furthermore,a predictive loss function that is more sensitive to high temperature regions of the image is designed. Additionally,for the sake of reducing the computing resource requirements of the algorithm,a model lightweight scheme that includes simplifying the encoder network structure and controlling the number of decoder channels is adopted. The experimental results on four data sets show that the proposed method can not only ensure high detection accuracy and robustness of the algorithm,but also meet the needs of real-time detection of patrol robots with detection speed above 40 f/s.

摘要：Mg–8Li–3Al–0.7Si alloy was prepared by casting and deformed by hot extrusion in this *** the microstructure of as-cast and extruded specimens was analyzed with OM,XRD,SEM and *** show that the specimens are composed ofα-Mg,β-Li,AlLi,MgLiAl2 and Mg2Si *** as-extruded specimen,the microstructure is refined and theβ-Li phase has the effect of coordination during *** hot extrusion,Chinese script Mg2Si phase is crushed into block-like and distributes uniformly in the *** properties results show that the strength and elongation are both improved after hot extrusion.

摘要：Based on the two-dimensional （2D） system theory, an integrated predictive iterative learning control （2D-IPILC） strategy for batch processes is presented. First, the output response and the error transition model predictions along the batch index can be calculated analytically due to the 2D Roesser model of the batch process. Then, an integrated framework of combining iterative learning control （ILC） and model predictive control （MPC） is formed reasonably. The output of feedforward ILC is estimated on the basis of the predefined process 2D model. By min- imizing a quadratic objective function, the feedback MPC is introduced to obtain better control performance for tracking problem of batch processes. Simulations on a typical batch reactor demonstrate that the satisfactory tracking performance as well as faster convergence speed can be achieved than traditional proportion type （P- t-we） ILC despite the model error and disturbances.

摘要：A 25-channel 200 GHz arrayed waveguide grating （AWG） based on Si nanowire wavegnides is designed, simulated and fab- ricated. Transfer function method is used in the simulation and error analysis of AWG with width fluctuations. The 25-channel 200 GHz AWG exhibits central channel insertion loss of 6.7 dB, crosstalk of-13 dB, and central wavelength of 1 560.55 nm. The error analysis can explain the experimental results of 25-channel 200 GHz AWG well. By using deep ul- traviolet lithography （DUV） and inductively coupled plasma etching （ICP） technologies, the devices are fabricated on sili- con-on-insulator （SOI） substrate.

摘要：A design of different microtextures on the surface of the crankpin bearing(CB)is proposed to ameliorate the lubrication and friction performance(LFP)of *** the basis of the CB s hydrodynamic lubrication model,the bearing surface of CB using different microtextures,such as wedge-shaped textures(WSTs),square textures(STs),circular textures(CTs),and combined square-circular textures(CSCTs),is simulated and assessed under various external loads of the CB at an engine speed of 2000 r/*** pressure of the oil film,the frictional force,the force of the solid asperity contact,and the friction coefficient of the CB are used as objective *** indicate that the bearing surface designed by the STs remarkably improves the CB s LFP in comparison with other structures of WSTs,CTs,and ***,the average values of the frictional force,solid asperity contact,and friction coefficient of the CB using the STs are greatly reduced by 28.5%,14.5%,and 33.2%and by 34.4%,26.3%,and 43.6%in comparison with the optimized CB dimensions and CTs,***,the application of the STs on the CB surfaces can enhance the LFP of engines.

摘要：Flexible lithium-sulfur(Li-S)batteries are considered one of the most promising candidates for highenergy-density storage devices in wearable ***,the safety problem severely restricts the practical application of Li-S batteries because of the possible occurrence of thermal runaway caused by battery short circuits and combustible components,particularly under bending *** development of advanced separators that can suppress lithium dendrite growth and are incombustible is the key to improving the safety of flexible Li-S *** this work,a nonflammable multifunctional Janus separator with self-extinguishing capability,high thermal stability,high thermal conductivity,good electrolyte infiltration,uniform lithium deposition,and efficient polysulfide shuttling inhibition,is *** separator is composed of polyacrylonitrile(PAN)fiber and decabromodiphenyl ethane(DBDPE)membrane as well as functional layers of boron nitride(BN)for suppressing lithium dendrite growth and reduced graphene oxide(rGO)for accelerating the sulfur convention *** a result,the Li-S battery with a sulfur mass loading of2.7 mg cm^(-2) delivers a specific capacity of 916.8 mA h g^(-1) after100 cycles at 0.1 C and maintains a stable performance during intermittent thermal ***,the Li-S pouch cell with a sulfur mass loading of 8 mg exhibits a high capacity of6.3 mA h under bending conditions.

摘要：Future climate change is usually projected by coupled earth system models under specific emission sce- narios designed by integrated assessment models （IAMs）, and this offline approach means there is no interaction between the coupled earth system models and the IAMs. This paper introduces a new method to design possible future emission scenarios and corresponding climate change, in which a simple economic and climate damage component is added to the coupled earth system model of Beijing Normal University （BNU-ESM）. With the growth of population and technological expertise and the declining emission-to-output ratio described in the Dynamic Inte- grated Climate-Economy model, the projected carbon emission is 13.7 Gt C, resulting in a 2.4℃ warming by the end of the twenty-first century （2080-2099） compared with 1980-1999. This paper also suggests the importance of the land and ocean carbon cycle in determining the CO2 con- centration in the atmosphere. It is hoped that in the near future the next generation of coupled earth system models that include both the natural system and the social dimension will be developed.

摘要：In the process of unprecedented urbanization in contemporary china, a great many of Chinese cities have witnessed a rapid expansion of urban scale to different degrees. With the continuous compilation, amendment and enforcement of urban planning, the functional structure, spatial environment, street patterns and textures and even the social aspect of cities have changed conspicuously, all of which have directly happened to the spatial forms of the dimension, or even the multi-dimension of a certain city. By describing and analyzing the structure, evolution and explicit tokens of the spatial forms of cities, this thesis attempts to set up a model of factors that affect urban forms, as well as discuss the attributes, protection, adjustment and development-potential of urban land closely associated with forms. In addition, on the basis of the professional features for urban design to participate in the modeling and construction-management of desirable spatial forms of cities, the author has put forward technical measures for quantitatively appraising and analyzing the large-scaled spatial forms of cities, thus offering technical support to municipal governments and management departments of planned construction.

摘要：The plastic deformation showing instability has been a subject receiving considerable attention for centuries due to its importance in many industrial *** Al alloys,the major instability is the Portevin-Le Chatelier(PLC)effect that appears within a certain region of strain,strain rate and *** manifests itself on the stress−strain curve as serrations associating with the rapid accumulation of plastic deformation within inclined slip *** PLC effect has severe practical consequences,which damages the surface quality after the sheet metal forming process and threatens the tensile ***,it is crucial to investigate the fundamental mechanisms underlying the PLC effect and in particular to investigate how it can be tempered by tailoring the material *** this paper,we review the common interpretations of the PLC effect and summarize the experimental results of the effects of the precipitation and the grain refinement,two conventional strengthening methodologies in Al alloys,on the serrated plastic *** effectiveness of solute atom clusters in suppressing the PLC effect is emphasized.