With the development of electric vehicle (EV), the estimation of battery state of charge (SOC) has attracted more and more attention. Accurate estimation of state of charge is very important for the energy management of electric vehicles. However, the accuracy of estimation has become the bottleneck of its development. Based on the analysis of impedance spectrum, a simplified impedance model of battery is derived by using constant phase element (CPE). By introducing EKF, a battery test platform is established, through the fusion with the EKF algorithm on the impedance model to estimate the SOC of lithium-ion battery accurately. The results of simulation and dynamic state test show that compared with other models and EKF algorithm, the SOC estimation method proposed has good performances in convergence and robustness, which could control the error within ±1%.

In order to solve the problems of low buck-boost conversion of super capacitor and large output voltage fluctuation in super capacitor energy storage system and increase the charging speed when boosting, a novel switching quasi-Z source bidirectional DC/DC converter is proposed. The converter adds two switch capacitors, which increases the voltage gain by 1/4 during the boost process, reduces the voltage drop coefficient by 1/5 during the step-down process, and reduces the voltage stress of the switch by 1/5. This paper introduces the working process of the super capcitor in the mode of step-up discharge and charging, and designs the voltage/current double closed-loop step-up control strategy. As a result, the output voltage fluctuation is less than 0.98% and the inductor current amplitude is reduced by 0.82 A. At the same time, the constant current to constant voltage step-down control strategy is designed, which increases the charging rate by 9.26%. MATLAB simulation is used to prove the characteristics and theoretical analysis of the proposed converter.

Speech emotion recognition is an important part of natural human-computer interaction. The traditional speech emotion recognition system mainly focuses on feature extraction and model construction. This paper proposes a speech emotion recognition method that directly applies deep neural network to the raw signal. The raw speech data carry the emotional information, two-dimensional spatial information and temporal context information of the speech signal. The model proposed is trained in an end-to-end manner, and the network automatically learns the feature representation of the raw speech signal without the need for manual feature extraction. The network model takes into account the advantages of both CNN and BLSTM neural networks. CNN is used to learn spatial features from the raw speech data, and then a BLSTM learning context feature is added. In order to evaluate the effectiveness of the model, recognition tests are carried out on IEMOCAP database, and the WA and UA obtained are 71.39% and 61.06% respectively. In addition, compared with the baseline model, the effectiveness of the proposed method is verified.

With the intensification of China’s aging population, home health care services have been required increasingly. In some large communities, due to the huge demand for home health care services, the scheduling of nursing workers has been regarded as something more important. However, this issue is only addressed in a few studies based on the premise of the known number of nursing workers, through which a reference for the service center to recruit the number of nursing workers of different levels cannot be provided. A caregiver scheduling algorithm, which is based on mean shift clustering and genetic algorithm, is proposed in this paper. And reasonable allocation of caregivers is made under the condition of completing all the elderly nursing tasks. In this algorithm, the elderly are clustered first according to the required caregiver grade and position to reduce the calculation scale; then genetic algorithms, real-number coding and elite retention strategies are all used to plan the service path of the caregiver to improve efficiency. Finally, the algorithm proposed in this paper is applied to real data. The results that the cost and the time required for path planning after clustering the elderly can be reduced effectively by the genetic algorithm is shown in this experiment. Through the analysis of the number of different levels of nursing workers required in the results, some suggestions are provided on the proportional relationship between the number of nursing workers required in each level and the number of the elderly served.

An image encryption algorithm based on DNA sequence and dynamic index diffusion is proposed to improve the efficiency and enhance the security of the encryption algorithm. Firstly, the SHA-256 hash function is used to generate the initial values related to plain image. Then, the plain-image is encoded into DNA matrix randomly. The DNA matrix is processed directly by using the new confusion method, and the confused DNA matrix is decoded randomly to obtain intermediate encrypted image. Finally, the intermediate encrypted image is diffused by using the dynamic index diffusion scheme to obtain the cipher image. Experimental results and security analysis prove that the encryption scheme has a good encryption effect, high key sensitivity, and can effectively resist various attacks, such as differential attack, statistical analysis attack, etc. In addition, the scheme has high encryption efficiency, which can meet the requirements of practical application.

The reasonable harvest of biological models is closely related to the rational exploitation and utilization of resources. There are many factors that affect biological models. Most models are linear. However, many phenomena cannot be explained by linearity. In order to study this problem more truly and appropriately, this paper studies a class of nonautonomous quasilinear predator-prey models with harvesting terms. First, the upper and lower solutions of the model are constructed by using the upper and lower solutions theory of quasilinear partial differential equations with harvesting terms, and the existence of the solutions is proved. Then, the unique sufficient conditions for the existence of the solutions are found in combination with relevant lemmas and properties. Finally, the optimal harvesting amount of the model is given by using variational method. Futhermore, the numerical simulation is given by MATLAB.

The connectedness of solution sets for vector optimization problems is studied in this paper. By means of the scalarization method, the connectedness of weakly efficient solutions sets for convex vector optimization problems on the unbounded, closed and convex sets are discussed. When the vector valued mapping is cone-lowersemicontinuous and cone-convex, the mapping of solution sets is proved to be upper semicontinuous and the connectedness of solution set by using the connectedness of the compact and convex base of the polar cone is established. When the vector valued mapping is cone-lowersemicontinuous and strictly cone-convex, the path-connectedness of solution sets of convex vector optimization problems are obtained. Furthermore, the connectedness of weakly efficient solutions sets of composite multiobjective optimization problems and the connectedness of solution sets of affine vector variational inequality problems are obtained.

The proposal of polar codes by Arikan in 2009 is a significant breakthrough in coding theory. It has been one of the hottest topics for researchers in the field of error-correcting codes in recent years, and has been widely applied in 5G communication systems, etc. This paper mainly deals with the polarization of hybrid multi-kernel polar codes which are generalizations of the conventional polar codes. Firstly, by introducing random switch channels, a lower bound for the symmetric capacities of parallel broadcast channels (PBCs) is generalized to the case that the constituent channels contain some asymmetric binary-input discrete memoryless channels (BIDMCs). Secondly, for the common tool of combining-and-splitting tactics (CAST) for the construction of polar codes, the restriction on symmetry and equivalence for the underlying channels are removed. Under the condition that the underlying channels are general BIDMCs, a lower bound for the largest symmetric capacity of the synthetic channels is generated by a CAST. Next, for any hybrid multi-kernel polar code, the exact relation between its coding matrix and the CASTs used in the iterative construction are determined. Finally, a rigorous proof for its polarization is demonstrated by using the lower bound on the symmetric capacity of synthetic channels generated by CASTs, when the underlying channel is a general BIDMC.

The synthesis law of MCM-56 molecular sieve was studied by changing the SiO₂/Al₂O₃,crystallization temperature and crystallization time under the conditions of oil bath heating and magnetic stirring reaction materials with HMI as template. The experimental results show that MCM-56 molecular sieves can not be obtained when the SiO₂/Al₂O₃ is 13.33,the crystallization temperature is 138-145 ℃,and the crystallization time is 5-8 days. When the ratio of SiO₂/Al₂O₃ is 16.67, although diffraction peaks appeare in the crystal faces of 100, 300 and 310 after 5 days and 7 days of crystallization at 138 ℃, the crystallinity is not high and the crystallization is not complete,the main structure of the products is amorphous. When the ratio of SiO₂/Al₂O₃ is 20.20 and the crystallization temperature is 138-145 ℃,the crystallized of MCM-56 molecular sieve can be obtained,and the specific surface area of the synthesized sample is 307.6 m²/g under the condition of crystallization under 138 ℃ for 7 days.

ZrO₂ supported Ru catalysts were synthesized with an impregnation-chemical reduction method using NaBH₄ as the reducing agent. The prepared catalysts were evaluated for the hydrogen generation via catalytic hydrolysis of BH₃NH₃. Effect of catalytic activity was investigated by varying the impregnated Ru loading, amount of reducing agent, reduction temperature as well as the reaction conditions. It was found that the TOF (Turnover Frequency) of 38.4 mol/mol(Ru)·min was achieved by adjusting Ru loading to 0.4 at 303 K of reaction temperature, while the molar ratio of Ru to NaBH₄ was 1:1.6. The Ru particle size of 3.2 nm was observed. Moreover, when the stirring speed was 450 r/min, external diffusion could be eliminated, leading to the highest reaction rate towards hydrogen generation. In addition, catalytic activity increased with enhancing the amount of used catalyst, indicating that catalytic hydrolysis of BH₃NH₃ towards hydrogen production was controlled by the interfacial reaction over the catalyst surface. Furthermore, with the reaction temperature increasing, it gets more suitable for the desorption of NaBO₂, the side product of hydrolysis of BH₃NH₃, from the catalyst surface. This results in the enhancement of the reaction rate towards hydrogen formation. According to the kinetic calculation, it suggests that the reaction rate of hydrolysis of BH₃NH₃ towards hydrogen generation over Ru/ZrO₂ is irrelevant to the concentration of BH₃NH₃. The activation energy is 66 kJ/mol.

In this paper, the effects of pH value, dosage, initial concentration, temperature and adsorption time on the adsorption of Cd(Ⅱ) and Cu(Ⅱ) by polygonum pubescens blume powder were studied by batch adsorption test with polygonum pubescens blume powder (hyperaccumulating manganese plant) as the research object. The adsorption mechanism was explored through kinetics, isothermal model fitting, FT-IR, SEM-EDS and XRD characterization analysis. The results showed that the optimum pH for adsorption of Cd(Ⅱ) and Cu(Ⅱ) by polygonum pubescens blume powder was 8 and 7, respectively, and the optimum dosage was 250 mg, and the adsorption equilibrium time was 60 min. The adsorption of Cd(Ⅱ) and Cu(Ⅱ) were in accordance with the quasi-second-order kinetic model. The adsorption of Cu(Ⅱ) was in accordance with Langmuir model, and the maximum theoretical adsorption capacity was 90.01 mg/g. The adsorption of Cd(Ⅱ) was in accordance with Freundlich model, and the maximum theoretical adsorption capacity was 62.69 mg/g. The adsorption thermodynamic analysis shows that the values of ΔG and ΔH are all negative, indicating that the adsorption process is spontaneous exothermic process. The results showed that the adsorption of Cd(Ⅱ) and Cu(Ⅱ) by polygonum pubescens blume powder were mainly carried out by hydrogen bonding, ion exchange and cation exchange-π interactions.

In order to effectively remove Cr(Ⅵ), a bacterial strain Pseudomonas sp. Cr13 that was remarkably removed Cr(Ⅵ) was isolated from mine contaminated soils in Dachang town. The Central Composite Design and response surface methodology were conducted to analyze the interactions among each factor. The optimal conditions for removing Cr(Ⅵ) by Pseudomonas sp. Cr13 were as follows: culture time of 30 h, Cr(Ⅵ) concentration of 60 mg/L, pH of 5.50, respectively. Under the optimized conditions, the removal rate of Cr(Ⅵ) by Cr13 strain was 72.05%. In conclusion, the optimized conditions by response surface methodology may improve the removal rate of Cr(Ⅵ), and it has a promising application prospect in the treatment of chromium-containing wastewater.

Analyzsis of the variation of soil temperature and moisture at different successional stages of Loropetalum chinense communities in karst hills of Guilin is a key basis for the understanding of the successional laws of L. chinense natural forests in karst hills of Guilin. The soil temperature and moisture sensors EM50 were used to continuously monitor temperature and humidity in different soil layers (0, 5 and 10 cm) of shrub stage, shrub to tree stage and small tree stage of L. chinense communities in karst hills of Guilin between March 2017 and February 2018. The variation of soil temperature and moisture at the three successional stages were analyzed. The study results indicated that, (1) The diurnal variation curve of soil temperature in different seasons showed the same sinusoidal curve in each soil layer at different successional stages of L. chinense communities. Except in summer, the diurnal variation of soil moisture was relatively stable. (2) The soil temperature of each soil layer reached the highest temperature in August (25.55±0.66—26.75±0.72 ℃) and the lowest temperature in January (9.13±2.82—11.04±1.90 ℃) at different successional stages, respectively. The soil moisture of each soil layer reached the maximum value from June to July (28.19%±1.99%—36.06%±3.86%) and minimum value from October to November (10.97%±1.09%—18.26%±0.44%). (3) The soil temperature of each soil layer decreased with succession in each month at different successional stages of L. chinense communities. And soil moisture of 0 cm layer increased with succession at different successional stages of L. chinense communities. In the deep soil layers, soil moisture didn’t show a obvious trend along the successional gradient of L. chinense communities. To sum up, the soil environment gradually recovered from high temperature and low humidity to low temperature and high humidity trend along the successional gradient of L. chinense communites. The results provide a theoretical basis for the synergy of natural succession development and environmental factors of L. chinense communities in karst hills of Guilin, China.

CYP2D subfamily genes are commonly found in primates and play an important role in drug metabolism. However, the effect of CYP2D enzyme on the metabolism of the same drug varies in different regions and races, and the CYP2D enzyme in non-human primates metabolizes some drugs more efficiently than that in humans. In addition, during the long evolutionary process, primate CYP2D subfamily genes will experience frequent gene duplication or gene loss, leading to differences in the number of CYP2D subfamily genes, but it has not been determined whether such differences are related to the species’ genetic relationship. In this study, we reviewed the studies on drug metabolism and evolution of CYP2D subfamily genes in primates, in order to provide some theoretical basis for the realization of individualized medication and precise therapy, and further understand the evolution of CYP2D subfamily genes in primates.

Karst rocky desertification of land is the most serious ecological problem in Southwest China, which threatens and restricts the sustainable development of the region. Taking the typical karst landform-Lijiang River basin as the study area, combining 6 natural environmental factors with 3 social environmental factors, based on GIS method and geographical detector method, the spatial distribution and key driving factors of karst rocky desertification in Lijiang River basin were analyzed. The results show that the total area of karst rocky desertification in Lijiang River basin is 1 547.6 km², accounting for 8.9% of the total land area of the Lijiang River basin, and the proportion of light, medium and severe karst rocky desertification in the total area of karst rocky desertification is 50.0%, 34.2% and 15.8%, respectively. In terms of space, Yangshuo County and Qixing District have the most extensive karst rocky desertification distribution, accounting for more than 18% of the total land area of their respective administrative regions. The middle and lower reaches of the Lijiang River are significantly more karst rocky desertification than the upper reaches. The contribution of natural environmental factors to karst rocky desertification is greater than that of social environmental factors. The influences of environmental factors from large to small are lithology, geomorphology, NDVI, elevation, road distance, population density, average annual precipitation, slope, and GDP. Lithology (0.34) and geomorphology (0.28) are the key driving factors of karst rocky desertification, and their explanatory power for the interaction of karst rocky desertification reaches 0.45.

Based on the air quality data of 29 cities in the central plains urban agglomeration from 2015 to 2018, spatial correlation network modeling is performed on the air quality of the central plains urban agglomeration, and the network index and community detection methods are used to explore the individual role and overall development trend of the air quality in the urban agglomeration. The results show that: (1) The air quality impact centers of the Central Plains urban agglomeration are divided into the northern strip center cluster with Jincheng as the core and the central block center cluster with Zhengzhou as the core. Among them, the northern cluster represents the significant influence of natural environmental conditions and unreasonable heavy industry structure on the northern region; the central cluster highlights the significant impact of the level of economic development and urbanization on urban air quality. In addition, Kaifeng, Xuchang, Luohe, Anyang, and Yuncheng, which have an intermediary role, are distributed at the edge of each circle in the urban agglomeration, which has a greater impact on air quality transmission. (2) The air quality spatial network integrity index of the Central Plains urban agglomeration reaches 0.512 3, which is closely related. The northwest plate with poor air quality environment in the urban agglomeration mainly affects the plate, and has a strong influence on the southeast plate at this stage. (3) The spatial correlation of air quality in the Central Plains urban agglomeration has obvious "gradient" characteristics, rather than exist in isolation. The community testing found that it has a relatively stable binary development trend. This paper analyzes the air quality of urban agglomerations through complex network theory, and aims to provide a scientific basis for preventing and controlling the overall air quality pollution of urban agglomerations.