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This article establishes an experimental platform for study of the thermal storage characteristics of solid thermal storage materials in low pressure environments. The experimental results show that under the influence of the thermal inertia of the heating section in low pressure environments, the thermal storage rates of thermal storage materials first increase to the peak, and then gradually decrease with the increase or decrease of the temperature of the thermal storage bricks. Air pressure has a significant impact on the heat storage rate of thermal bricks: compared to a 101kPa atmospheric pressure environment, under the same heating temperature, the heat storage time of 80kPa and 40kPa is significantly increased, and the lower the air pressure, the longer the heat storage time required.

In order to improve the frequent Doppler bias in the high-speed mobile scenario, improve the communication quality on HSR (High-Speed Railway). An algorithm can improve communication performance through RIS (intelligent metasurface) phase optimization. The optimization process is modeled as a reinforcement learning task, where the agent in the channel learns to select the optimal RIS phase by interacting with the environment to reduce the effect of Doppler shift.The model covers characteristic parameters such as signal propagation path and frequency related to RIS, and the agent influences the beam direction by adjusting the phase, and learns the optimal phase configuration in the high-speed moving scene.The RIS phase optimization method implemented based on the deep reinforcement learning algorithm has high convergence and has significant advantages in improving the Doppler frequency shift problem. Compared with the traditional frequency bias estimation method, this method can significantly improve the transmission performance. The effectiveness of the proposed algorithm is verified by performing large-scale training and evaluation in the simulation environment.

Current studies lack a comprehensive understanding of the status of carbon emission reduction in international shipping from the perspectives of policies and measures, which tends to increase uncertainty in policy-making. The study aims to use a structured review approach to systematically collect and analyse carbon reduction policies as well as technical, regulatory, and economic measures in international shipping in recent years to support international shipping carbon neutrality decisions. The results show that most regions are committed to achieving zero emissions by 2050, but the reduction targets of international maritime organizations are lagging; while hydrogen, ammonia and green methanol fuels and ship wind power have a high potential to advance emission reduction, they are still limited by technology, regulation, cost and support; market-based trading measures can reflect emission reduction targets, but carbon prices are not yet mature; other measures also suffer from emissions shifting, low emission reduction potential or unsustainability. Tracking the progress of policies and measures to reduce carbon emissions in international shipping benefits to “know yourself as well as the enemy” for supporting decisions.

With the development of new media technology, some new changes have been brought to traditional shopping. In this environment, live streaming e-commerce has been loved by online consumers. We adopted the theory of planned behavior (TPB), perceived interactivity and perceived utilitarian value as the theoretical basis for research. In the part of data collection, we surveyed 600 Chinese online consumers, the results showed that attitude, subjective norms, perceived behavior control, perceived interactivity and perceived utilitarian value significantly affected consumer behavior intention. The article also discussed the practice and theoretical contributions for live streaming e-commerce.

COVID-19 is a severe disease and has now spread around the world as a highly infectious pandemic. COVID-19 has rapidly and deeply affected our daily life, and most countries have taken measures to prevent the spread of this disease, such as restricting entry and centralized isolation. Contactless delivery is a non-face-to-face delivery method which help ensure sufficient distance between the rider and the customers, thus further reduces the pandemic transmission risk. While relatively few people know and adopt this service. This study used the theory of planned behaviour to investigate people’s intention to adopt contactless home delivery services during COVID-19. Research results provide both contributions to academics and practitioners.

This research extends the theory of planned behavior to explore how privacy concerns influence privacy-protection behavioral intentions via attitudes, subjective norms, and perceived behavioral control. Using snowball sampling, 637 participants were recruited in China to complete this online survey. After eliminating the invalid questionnaire, this study received valid samples of 599 respondents. The finding demonstrated that privacy concerns were positively associated with individuals’ attitudes, subjective norms, and perceived behavioral control. And these factors also were found positively influence privacy-protection behavioral intentions. Theoretical and practical contributions are discussed as well.

In this paper, we address the lack of specific targeting of β-amyloid β-protein (Aβ) in the current Alzheimer's disease (AD) diagnosis and treatment, and build a novel AIE nanoprobe molecule based on molecular design and nano-self-assembly technology. Based on the molecular design and nano-self-assembly technology, a new two-component AIE nanoprobe molecule with integrated AD diagnosis and treatment was constructed by co-assembling two-component AIE components. The NIR AIE nanomolecule can effectively penetrate the blood brain barrier (BBB) and depolymerize Aβ fibers, alleviate reactive oxygen species (ROS) in the focal area, and achieve highly sensitive imaging and specific depolymerization.

With the improvement of China’s electrification level, the relationship between electricity power consumption and social economy development is getting closer. Under this background, in this paper, the business cycle analysis method is applied to the electricity power industry in Hebei Province, and the link between electric power generation and economic development is determined through the prosperity index. First of all, the steps and methods of business cycle analysis were introduced, and the time-difference grey correlation method considering the consistency of time series to screen indicators was put forward, thus to reduce the number of indicators. Next, Hebei Province was taken as an example, and its monthly data related to power generation and economic growth in the 10 years from 2009 to 2018 to was selected to build the business cycle indicator system, at last the composite prosperity index of Hebei Province in electric power industry was calculated. This research results manifest that it is feasible to apply the business cycle analysis to the power industry.

High efficiency heat exchanger is always a hot topic, and field synergy theory is introduced as an important means to optimize the heat transfer efficiency. Based on the field synergy theory, a new type of heat exchanger is proposed in this paper, in which, the cold and hot fluid presents reverse cross flow law. Through the verification of the test and numerical simulation results, a reasonable numerical simulation model and method are obtained. Then, the flow and heat transfer conditions of the new structure heat exchanger are simulated by the verified numerical simulation technology. The conclusion is as follows: K-ε turbulence model and coupled heat transfer model can be effectively used in the numerical simulation of heat exchanger. And the reverse cross convection heat exchanger can effectively improve the uniformity of water temperature distribution in the heat exchanger.

With the development of society, the demand for energy is increasing significantly, and the environmental problems are becoming more and more serious. Therefore, it is urgent to find efficient and clean new energy. Among the many new energy sources, solar energy has been favoured most for its universality, harmlessness and low cost. In 1991, the photoelectric conversion efficiency of dye-sensitized solar cells (DSSCs) has been greatly improved, which has attracted the attention. In recent 30 years, the researches on DSSCs have been increasing and expanding. Dye sensitizer is the most important component of DSSC, and also a key issue of researchers. This paper aims to summarize the types, structures and development trends of dye sensitizers, and provide inspiration for us to design and evaluate new dye sensitizers.

Under the background of the rapid development of Internet technology, the emergence of Internet platform accelerates the industrial agglomeration. As a chain connecting the material circulation between industries, the rise of logistics industry is inevitable. As a key link of logistics industry, transportation, along with the rise of logistics industry, has led to an increase in traffic accidents year by year. Therefore, based on the national road traffic accident data from 2006 to 2019, this paper uses SPSS 26.0 to analyse the accident incidence, casualties and direct property loss indicators of different regions and occupation, and study the characteristics of perpetrators and casualties. The results show that the traffic accidents in the whole country show a downward trend, but they are unbalanced. Workers and farmers accounted for the largest proportion, but the death and injury rate showed a downward trend. Other showed an upward trend in the past five years, especially in the delivery industry. Future road traffic safety management should take corresponding measures to reduce the accident rate from the perspective of the development of related industries.

Most of the research on the cavitation with entrained air has focused on the military direction, but it ,about centrifugal pumps, which is relevant to people's livelihood, is still relatively lacking. In order to study the basic law of the development of cavitation inside centrifugal pumps under aeration conditions, a test bench suitable for cavitation experiments with incoming flow containing gas was obtained. Furthermore, a single-stage single-suction 6-blade centrifugal pump was used as the research object to conduct pressure pulsation experiments under cavitation condition when the incoming flow was 1.0% air viod fraction at 2900r/min-50m3/h. The results showed that: After cavitation happened, the greater aeration content will deteriorate the pump's anti-cavitation performance, but the head curve is more gentle in falling down compared to natural cavitation. Hence aeration has a beneficial effect on the performance degradation of the pump under the cavitation condition. At the same time, before the cavitation number drops to the fracture cavitation number of the pump, aeration has improvement in the efficiency of the pump in different degrees , especially in the situation with the ventilated rate of 1.0%. The main frequency of pressure pulsation at the inlet and outlet of the test pump after aeration is dominated by the blade frequency. The shaft frequency signal at the outlet gradually decreases with the cavitation number lessened. Moreover the amplitude of the blade frequency grows slightly with the reduction of the cavitation number. But it tends to soar when the cavitation number is less than the fracture cavitation number.

In this paper, 18 towns of Jinyun were analyzed. Natural conditions (average elevation, relative height difference, and gully density), socio-economic status(population density, and per capita disposable income), characteristics of soil erosion (area ratio of soil erosion, area ratio of soil erosion above moderate), and the present state of soil and water conservation, (vegetation coverage) were calculated. Self-organizing Feature Maps (SOFM) was used for soil and water conservation regionalization. Through the analysis of the 18 towns in Jinyun, two first-order classes and five second-order types were identified. The results showed that the classification results were consistent with the actual characteristics, and the feasibility of using SOFM for classification of soil and water conservation regionalization has been demonstrated through this study.

The constructed wetland project of tailwater from an urban sewage plant in central Zhejiang was selected to collect water samples in different seasons, and the samples were tested for chemical oxygen demand (COD), total phosphorus (TP), total nitrogen (TN) and other indicators. The results showed that the operation effect of the constructed wetland project is good when the effluent from the sewage treatment plant meets the Class A discharge standard. Among them, the removal effect of TP was the best, with an average removal rate of 61.52%, reaching the standards of surface water class III and class IV in some tests. Besides, the removal effect of TP was stable and varies little with seasons. The removal rates of COD and TN were relatively low and varied greatly with seasons, which were higher in spring and summer than in autumn and winter, with a negative removal rate of TN in winter. This research provides practical data for optimizing the engineering design parameters and improving the operation management to promote the operation efficiency of the constructed wetland.

TS-1 zeolite has outstanding performance in the catalytic reactions with hydrogen peroxide as catalytic promoter. However, the narrow pore size (< 1.0 nm) of traditional TS-1 makes it difficult for bulky organic compounds to contact with the active sites in the pores, which seriously limits application of TS-1. Recently, the introduction of mesoporous structure into microporous TS-1 becomes a hot research topic. Meanwhile, the huge synthesis cost of TS-1 is another main reason hindering its industrial application. In this paper, mesoporous TS-1 was successfully synthesized using sodium silicate as silicon source and titanium trichloride as titanium source under the template conditions of tetrapropylammonium hydroxide (TPAOH) and cationic polymer. The mesoporous TS-1 was characterized by X-ray diffraction (XRD), N2 adsorption, scanning electric microscopy (SEM), transmitting electric microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR) and UV-Vis Spectrum spectra (UV-Vis). Results show that the synthesized TS-1 zeolites have good crystallinity and tetra-coordinated framework Ti atoms, and there are abundant mesoporous structures in the zeolite crystals. The results of oxidation experiments show that conversion of diphenyl sulfide and dibenzyl sulfide with mesoporous TS-1 are 97.3 % and 85.3 % respectively, while that conversion with microporous TS-1 are 75.7 % and 63.5 respectively.

In order to make the silage equipment control panel meet user needs better and translate user requirements into product design elements, this paper puts forward the design model of silage equipment control panel based on the theory of emotional design and Kansei Engineering. Firstly, qualitative and quantitative analyses of silage equipment control panel were conducted according to the results of the user survey. Then, the prior design elements and the “Feature-Vocabulary” correspondence were obtained, which were applied to the design of silage equipment control panel. Finally, the design plan was evaluated using semantic differential method. As a result, it is initially verified that the design model has certain feasibility for translating user requirements into product design elements.

In view of the distortion in the filter gain matrix calculation as well as the high computational complexity and the nonlocal effect of symmetric sampling that exists in the UKF-SLAM algorithm, the square root UKF-SLAM algorithm based on the smallest proportion of skewness in single line sampling was proposed. According to the mended algorithm, the square root of covariance matrix is brought into iteration operation instead of covariance matrix, moreover, the smallest proportion of skewness in single line sampling is utilized for the optimization of sampling strategy. The results of simulation show that the algorithm can effectively improve the position accuracy in robot as well as the estimation accuracy of feature map. Furthermore, the computational complexity is reduced and the algorithm stability is improved.

This paper is based on the effect of precursors’ structure on the resultant electropolymers’ electrochemical and optical and thermal properties. The polyacrylate functionalized thiophene with a narrow polydispersity index (PDI) was synthesized by means of reversible addition-fragmentation chain transfer (RAFT) polymerization, and then the free-standing and conducting conjugated polyacrylate functionalized polythiophene (R-PTE-PAA) film was prepared through electropolymerization in CH2Cl2 with 50% BFEE (boron trifluoride diethyl etherate). For comparison, the polyacrylate functionalized polythiophene (PTE-PAA) was also prepared with the precursor of a broad PDI from conventional free radical polymerization. The prepared polymers were characterized by UV-vis, FT-IR spectroscopy, thermogravimetry, cyclic voltammetry, scanning electron microscopy and fluorescence spectrophotometry. The R-PTE-PAA film showed the excellent electrochemical behavior, good blue-light property and high thermal stability. Compared with PTE-PAA, the R-PTE-PAA film presented the better electrochemical reversibility and stability. The results obtained in the present study indicate that the R-PTE-PAA film would be important for applications in electrochromics, supercapacitors and electrochemical sensors.

Ecological environmental issues are constantly threatening the survival and development of human society and has been concerned by all walks of life. The seven ecological efficiency factors proposed by the WBCSD are the basis for improving the ecological performance. Through the mapping relationship between ecological efficiency factors and 39 engineering parameters, the ecological issues will be transferred to engineering problems. It is guided by the corresponding design concepts. Furtherly the TRIZ problem solving tools will be applied. Thereby, the optimized solution will be obtained. It can not only effectively reduce the environmental impact of products, but also can shorten the development cycle of green products while satisfying functional requirements. The development of China’s agricultural machinery is extensive. This method is used to implement ecological optimization design of the bundling device mounting frame for silage equipment, which has important guiding significance for the development of China's agricultural machinery.

This document explains how post-humanism theory has been a hot topic in many of films and animations. This paper will describe the topic in detail, and select few examples of films and animations to dress about how directors approach this topics using plot, narration in the films.

B and Ga co-doped ZnO films were fabricated by RF magnetron sputtering method. The effects of sputtering pressure on the electrical, optical, structural and morphological properties of the films (BGZO) were investigated. As sputtering pressure increased up to 6mTorr, the film crystallinity was improved. At the sputtering pressure of 6mTorr, the films showed smooth and dense of film surface, lower resistivity and higher Hall mobility. It was also observed that all films showed high transparency in the visible range. The film showed blue shift of optical band gap with increaseing of sputtering pressure.

With the rapid development of Internet, image information is growing. It requires a lot of image storage and transmission. In order to reduce the storage and get better image quality, image compression algorithm is studied. The paper proposes a new image compression algorithm that combines principal component analysis (PCA) and Contourlet Transform (CT). Because PCA has good image quality, but the compression ratio is low, and CT compression algorithm has high compression ratio and good PNSR value. The image is decomposed by PCA. The image data is divided into blocks, and each block is used as a sample vector, then select covariance matrix of k larger eigenvalues corresponding eigenvector to realize image compression. Then the image is compressed again using CT compression algorithm. Compared with the results of JEPG2000 and CT compression algorithm, the results show that the proposed algorithm has better performance than JEPG2000 and CT compression algorithm. In the same compression ratio, PNSR value of proposed algorithm is about 3dB higher than that of JEPG2000, and 2dB higher than that of CT compression algorithm.