Study on a New Spline Adaptive Filter Using Convex Combination of Exponential Hyperbolic Sine

In this paper, a new spline adaptive filter using a convex combination of exponential hyperbolic sinusoidal is presented. the algorithm convexly combines an exponential hyperbolic sinusoidal Hammerstein spline adaptive filter and a Wiener-type spline adaptive filter to maintain the robustness in non-Gaussian noise environments when dealing with both the Hammerstein nonlinear system and the Wiener nonlinear system. The convergence analyses and simulation experiments are carried out on the proposed algorithm. The experimental results show the superiority of the proposed algorithm to other algorithms.

基于粉末微波发泡法制备超轻质聚酰亚胺泡沫的结构与性能

以3,3′,4,4′-二苯甲酮四羧基二酐和4,4′-二氨基二苯醚为主要原料,采用简单高效的粉末微波发泡法制备了一系列超轻质开孔柔性聚酰亚胺泡沫,克服了液相发泡法易掉渣的不足。泡沫密度6~200kg/m^3可调,厚度1~400mm可调,最大宏观尺寸可达1000mm×1000mm。对泡孔结构和性能进行了测试,分析了发泡原理,探究了高温下材料的拉伸、隔热和真空出气性能。结果表明,泡沫玻璃化温度达265℃、5%失重温度达560℃;随着密度由6kg/m^3增加至60kg/m^3,泡沫开孔率由99.1%降低至95%,拉伸强度由0.08MPa增加至0.92MPa,150℃时泡沫拉伸强度几乎不变;室温热导率则表现为先降低后增加的趋势,热端温度250℃,泡沫热导率均小于0.1W/(m·K);150℃的真空质量损失仅为0.947%,远低于液相发泡法的泡沫。

Branching Process based Cascading Failure Probability Analysis for a Regional Power Grid in China with Utility Outage Data

Studying the propagation of cascading failures through the transmission network is key to asses and mitigate the risk faced the energy system. As complex systems the power grid failure is often studied using some probability distributions. We apply 4 well-known probabilistic models, Poisson model, Power Law model, Generalized Poisson Branching process model and Borel-Tanner Branching process model, to a 14-year utility historical outage data from a regional power grid in China, computing probabilities of cascading line outages. For this data, the empirical distribution of the total number of line outages is well approximated by the initial line outages propagating according to a Borel-Tanner branching process. Also for this data, Power law model overestimates, while Generalized Possion branching process and Possion model underestimate, the probability of larger outages. Especially, the probability distribution generated by the Poisson model deviates heavily from the observed data, underestimating the probability of large events (total no. of outages over 5) by roughly a factor of 10-2 to 10-5. The observation is confirmed by a statistical test of model fitness. The results of this work indicate that further testing of Borel-Tanner branching process models of cascading failure is appropriate, and should be further discussed as it outperforms other more traditional models.

Application and Development of Computer and Software Technology in the Field of Sports

This paper expounds and summarizes the application situation of modem information technology in the current sports field in our country, and prospected its future development trend. At the same time, Chinese perception is an important strategic thought for development and application of network technology in China, represents the important development direction of information technology in the next generation. The perception sports can be considered using the Internet of things technology to develop and utilize sports resources, thus realize the wisdom management and effective monitoring of sports system, ultimately to serve the sports powerful nation strategy.

Biomechanical analysis of bone mesoscopic structure and mechanical properties of vertebral endplates of degenerated intervertebral discs in rabbits

In previous studies of disc degeneration,the structural and mechanical properties of the endplate were often neglected.In this paper,the station legislation was used to construct an animal model of minor trauma disc degeneration,and the mechanism of disc degeneration was further investigated by observing the changes of mesoscopic structure and developing the mechanical properties of endplate bone.Twenty-eight 6-month-old Japanese white rabbits were divided into two groups:control group and experimental group.An animal model of intervertebral disc degeneration was established by upright experiment in the experimental group.The bone mesoscopic structures in different areas of each endplate were observed by histological and imaging methods,and the mechanical properties of the endplates were measured by indentation method.The two groups of data were compared by one-way ANOVA.After the experimental animals stood for 17 weeks,The experimental group showed the characteristics of early disc degeneration.The microstructure of the degenerative group showed that the end plate mineralization degree was higher,the bone mass was larger,and the number and thickness of bone trabeculae were larger.The results of indentation test showed that the mechanical properties of the degeneration group were enhanced,and the lower endplate was obviously enhanced.We successfully established a model of human disc degeneration with non invasive trauma and more consistent with the process of human disc degeneration through the standing experiment.In the experimental group,the internal structure of the endplate was dense and pore distance was reduced.The change of bone mesoscopic structure further affects the endplate,resulting in the enhancement of the mechanical properties of the endplate after intervertebral disc degeneration.The reduction of the pore distance and the narrowing of the internal channel structure of the endplate also hinder the nutrition supply of the intervertebral disc,which may be the key reason affecting the degeneration of the intervertebral disc.A biomechanical method for investigating the mechanism of intervertebral disc degeneration can be provided in this paper.

Photocatalytic degradation of tetracycline by copper(I)oxide loaded on Daylily Stalk derived carbon material

In this work,Daylily Stalks derived N doped carbon material(N-DSC)with a high specific surface area was firstly prepared by a chemical activation method,and then cubic Cu_(2)O nanoparticles were combined with the prepared N-DSC to obtain N-DSC/Cu_(2)O composite as the catalyst for the photocatalytic degradation of tetracycline(TC)antibiotics under visible light.It is found that the obtained composite had higher photocatalytic activity than pure Cu_(2)O.Particularly,25 wt%N-DSC/Cu_(2)O composite showed the highest photocatalytic performance with 95%of TC degradation within 100 min and more excellent stability.Combined with various characterizations,it is confirmed that carbon bonds should be conducive to the separation of photoelectron and hole,and the carbon layer with an excellent electrical conductivity on Cu_(2)O can reduce the charge transfer resistance between N-DSC and Cu_(2)O,thereby improving the absorption of visible light and enhancing the photocatalytic activity.Moreover,it is considered that the synergistic effect of photo-generated electron pair in Cu_(2)O and N-DSC could promote the photodegradation efficiency of N-DSC/Cu_(2)O composite.In addition,the active species capture experiment confirmed that·OH and·O_(2)should be the main active species for TC degradation under visible light.This study is expected to provide a novel low-cost photocatalysts for pollutants removal.

Organic ionic plastic crystal as electrolyte for lithium-oxygen batteries

Organic ionic plastic crystals (OIPCs) composed of 1-ethyl-1-methyl pyrrolidinium bis(fluorosulfonyl) imide (P12FSI) and lithium bis(fluorosulfonyl)imide (LiFSI) was used as electrolyte for lithium-oxygen batteries. Since P12FSI-LiFSI electrolyte exhibited high ionic conductivity, good chemical stability and wide electrochemical window, the battery showed good rate capability, excellent cycling stability and can be operated stably for 320 cycles under a fixed capacity of 500 mAh/gcarbon. The use of OIPCs electrolyte could provide a new avenue for the development of high-performance Li-O2 batteries.

Recent Advancements in Photoelectrochemical Water Splitting for Hydrogen Production

Sunlight is the most abundant and inexhaustible energy source on earth.However,its low energy density,dispersibility and intermittent nature make its direct utilization with industrial relevance challenging,suggesting that converting sunlight into chemical energy and storing it is a valuable measure to achieve global sustainable development.Carbon–neutral,clean and secondary pollution-free solar-driven water splitting to produce hydrogen is one of the most attractive avenues among all the current options and is expected to realize the transformation from dependence on fossil fuels to zero-pollution hydrogen.Artificial photosynthetic systems(APSs)based on photoelectrochemical(PEC)devices appear to be an ideal avenue to efficiently achieve solar-to-hydrogen conversion.In this review,we comprehensively highlight the recent developments in photocathodes,including architectures,semiconductor photoabsorbers and performance optimization strategies.In particular,frontier research cases of organic semiconductors,dye sensitization and surface grafted molecular catalysts applied to APSs based on frontier(molecular)orbital theory and semiconductor energy band theory are discussed.Moreover,research advances in typical photoelectrodes with the metal–insulator–semiconductor(MIS)architecture based on quantum tunnelling are also introduced.Finally,we discuss the benchmarks and protocols for designing integrated tandem photoelectrodes and PEC systems that conform to the solar spectrum to achieve high-efficiency and cost-effective solar-to-hydrogen conversion at an industrial scale in the near future.

Ultrathin salt-free polymer-in-ceramic electrolyte for solid-state sodium batteries

The practical energy density of solid-state batteries remains limited,partly because of the lack of a general method to fabricate thin membranes for solid-state electrolytes with high ionic conductivity and low area-specific resistance(ASR).Herein,we use an ultrahigh concentration of a ceramic ion conductor(Na_(3)SbS_(4))to build an ionconduction“highway”,and a polymer(polyethylene oxide,2 wt%)as a flexible host to prepare a polymer-inceramic ion-conducting membrane of approximately 40μm.Without the use of any salt(e.g.,NaPF_(6)),the resulting membrane exhibits a threefold increase in electronic ASR and a twofold decrease in ionic ASR compared with a pure ceramic counterpart.The activation energy for sodium-ion transport is only 190 meV in the membrane,similar to that in pure ceramic,suggesting ion transport predominantly occurs through a percolated network of ion-conducting ceramic particles.The salt-free design also provides an opportunity to suppress dendritic metal electrodeposits,according to a recently refined chemomechanical model of metal deposition.Our work suggests that salt is not always necessary in composite solid-state electrolytes,which broadens the choice of polymers to allow the optimization of other desired attributes,such as mechanical strength,chemical/electrochemical stability,and cost.

Characterization of a new total heat recovery system using CaCl_(2) as working fluid:Thermal modeling and physical analysis

This paper introduces a kind of open cycle absorption heat wet flue gas heat recovery system,which use CaCl_(2) as the working medium.The system will use the wet heat recovery method and combined with an efficient heat pump system for flue gas as a heat source generator.Through direct contact with the solution in the absorber,the flue gas is going to carry out gas,liquid heat transfer between heat exchanger,realization of sensible heat and latent heat step by step.As the key part of the system,absorber is established by one-dimensional steady-state heat transfer and mass transfer model.This paper uses the finite difference method to model the discrete numerical methods,and an-alyzes the characteristics of heat and mass transfer in the absorber.We obtain the concentration curves of the three kinds of working medium’s temperature and flow along the height direction.We also analyze the influence of CaCl_(2) solution parameters changes on the absorption process,parsing the reason of the temperature change by analyzing the three working medium’s energy flow trend.We found that the temperature change of flue gas is non-monotonic,which decreases gradually in the range of absorption tower height 0-0.9 m,and then increases gradually.The reason for this change is that sensible heat exchange and latent heat exchange exist between flue gas and solution.Although such a change has an impact on the efficiency of the system,it prevents the"white smoke"from condensing in the air,which effectively protects the environment.Compared with conventional LiBr absorption heat pump,the system constructed in this paper has certain advantages in latent heat recovery,flue gas heat energy utilization,energy conservation and emission reduction and economy.