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Human milk oligosaccharides (HMOs), an important bioactive ingredient in breast milk, have become a popular nutritional fortifier in infant formula. While only a limited variety of synthetic functional oligosaccharides is available now, naturally occurring oligosaccharides from animal milk are a promising substitute for HMOs. Goat milk oligosaccharides (GMOs) are rich in neutral oligosaccharides, which are more similar in structure to HMOs. However, most studies on the separation of milk oligosaccharides concentrate on bovine milk oligosaccharides, while little research has been done on milk oligosaccharides from animal species other than cows, and the structure and composition of animal milk oligosaccharides are different from those of HMOs. In addition, there are few systematic studies on the structures and functions of oligosaccharides, which limits the development and utilization of oligosaccharides in animal milk. This review summarizes the latest progress in research on oligosaccharides in animal milk with a focus on the structures, detection methods and physiological functions of GMOs, and it compares and analyzes the structural differences between animal milk oligosaccharides and HMOs. It is anticipated that this review can provide theoretical support for the development and application of animal milk oligosaccharides in the future.

The accurate rockburst prediction is crucial for ensuring the safety of underground engineering construction. Among the various methods, machine learning-based rockburst prediction can better solve the nonlinear relationship between rockbursts and influencing factors and thus has great potential for engineering applications. However, current research often faces certain challenges related to the feature selection of prediction indices and poor model optimization performance. This study compiled 342 rockburst cases from domestic and international sources to construct an initial database. In order to determine the relevant prediction indicators, a feature selection method based on the ReliefF-Kendall model was proposed. The initial database was equalized and visualized using the Adasyn and t-SNE algorithms. Five rockburst prediction models [support vector machine (SVM), least-squares support vector machine (LSSVM), kernel extreme learning machine (KELM), Random Forest (RF), and XGBoost] were established by employing the Secretary Bird Optimization (SBO) algorithm and 5-fold cross-validation to optimize performance. The optimal model was selected based on a comprehensive assessment of generalization ability (accuracy, kappa, precision, recall, and F1-score) and stability (average accuracy). The reliability of the proposed feature selection, model optimization, and data balancing methods was verified by comparing the optimal model with other methods. The results indicate that the PSO-SVM model demonstrated superior prediction accuracy and generalization performance; the accuracy can reach 81.4% (optimal) and 80.1% (average). The main factors affecting the occurrence of rockburst are Wet, maximum tangential stress (MTS), D, and uniaxial compressive strength (UCS). Finally, the model was applied to the domestic rockburst engineering cases, achieving a prediction accuracy of 90% and verifying its engineering applicability.

Harmonics are an important cause of voltage distortion, and voltage reduction and voltage distortion are the main causes of commutation failure. But most of the current research studies on commutation failure are based on the drop in fundamental voltage after a fault, and there are few reports on the impact of voltage distortion on commutation failure. Aiming to solve the above problem, this article first analyzes the generation and transmission characteristics of harmonics in AC and DC systems, as well as the coupling degree of harmonics in DC systems. Then, starting from the mechanism of the commutation process, a commutation failure analysis method based on the harmonic voltage time area is proposed. This method can quantitatively analyze the impact of different harmonics on commutation failure. On this basis, the harmonic criteria for causing commutation failure are established, and the harmonic characteristics of AC voltage when harmonics cause subsequent commutation failure are quantitatively analyzed. Finally, a preventive controller is proposed to suppress commutation failure caused by different harmonics, where the above analysis is verified by the simulations.

Abstract Sequential immunotherapy has shown certain advantages in malignancy. Here, we aim to evaluate the efficacy of sequential anti-CTLA-4 and anti-PD-1 treatment for recurrent or metastatic nasopharyngeal carcinoma patients (R/M NPC). We retrospectively analysis 2 phase I trial of ipilimumab and camrelizumab in Chinese R/M NPC patients. These patients were initially treated with ipilimumab, a CTLA4 blockade, followed by anti-PD-1 treatment. We observed a durable tumor remission in these patients (mPFS: 12.3 months; mDoR: 20.9 months). Multimodal investigations of biopsy samples disclosed remodeling of tumor-immune microenvironment triggered by ipilimumab. In responders, we found increased tumoral PD-L1/PD-L2 expression and T-cell infiltration after ipilimumab treatment, accompanied by reduced stroma and malignant cell components. In contrast, non-responders exhibited increased B-cell infiltration and increased peripheral CD19 + B cells, suggesting a defective transition from memory B cells to plasma cells. This study proposes that sequential therapy can potentially enhance treatment efficacy in chemotherapy-resistant NPC patients and provides insights into how preexisting anti-CTLA4 blockade can influence subsequent anti-PD-1 efficacy by remodeling the TME. Additionally, our results highlight the need for therapeutic strategies targeting naïve/memory B cells.

Based on properties of Green's function and the some conditions of $ f(t, u) $, we found a minimal and a maximal positive solution by the method of sequence approximation. Moreover, based on the properties of Green's function and fixed point index theorem, the existence of multiple positive solutions for a singular $ p $-Laplacian fractional differential equation with infinite-point boundary conditions was obtained and, at last, an example was given to demonstrate the validity of our main results.

Water-soluble inorganic ions (WSIIs) can increase the hygroscopicity of aerosols, which will transform aerosols into larger sizes and reduce visibility by enhancing light scattering. To explore the characteristics of WSII concentrations and their impacts on visibility in a coastal airport, in this study, PM1.0 samples at two monitoring sites (including airport site and background site) were collect in spring and summer, and 12 species of ions were detected. In general, secondary water-soluble inorganic ions (SNA, including SO42−, NO3− and NH4+) and Ca2+ were the dominant WSIIs in PM1.0, contributing about 89% to 95% of the total measured ions. The continental contributions of SO42−, K+, and Ca2+ accounted for more than 60% during the whole period, while Na+ and Cl− were mainly from marine sources. The source identification showed that airport emissions were a major source at the sampling site and significantly contributed to the levels of sulfate, nitrate, and ammonium. Agricultural activities were the dominant sources impacting visibility in spring, while airport emissions and secondary inorganic aerosols were the main components affecting visibility in summer. Therefore, improving atmospheric visibility in coastal airport areas should focus on reducing the precursors of secondary particulates and reducing biomass-burning activities.

To address the instability of wind power caused by the randomness and intermittency of wind generation, as well as the challenges in power compensation by hybrid energy storage systems (HESSs), this paper proposes a state of charge (SOC) balancing control strategy based on Successive Variational Mode Decomposition and multi-fuzzy control. First, a consensus algorithm is used to enable communication between energy storage units to obtain the global average SOC. Then, the Secretary Bird Optimization Algorithm (SBOA) is applied to optimize the Successive Variational Mode Decomposition (SVMD) and Variational Mode Decomposition (VMD) for the initial allocation of wind power, resulting in the smoothing power for hybrid energy storage and the grid integration power. Finally, considering the deviation between the current SOC of the storage units and the global average SOC, dynamic partitioning is used for multi-fuzzy control to adjust the initial power allocation, achieving SOC balancing control. Simulations of the control strategy were conducted using Matlab/Simulink, and the results indicate that the proposed approach effectively smooths wind power fluctuations, achieving stable grid integration power. It enables the SOC of the HESS to quickly align with the global average SOC, preventing the HESS from entering unhealthy SOC regions.

To address the common issues of accuracy and stability in trajectory tracking tasks for autonomous vehicles, this study proposes an innovative composite control strategy that skillfully integrates lateral and longitudinal dynamic control. For lateral control, model predictive control (MPC) theory is introduced to compute the front wheel steering angle that ensures optimal trajectory following. On the longitudinal control level, the vehicle’s acceleration and deceleration logic are finely tuned to ensure precise adherence to the preset speed trajectory. More importantly, by deeply integrating these two control methods, the comprehensive coordination of the vehicle’s lateral and longitudinal movements is achieved. To validate the effectiveness of the proposed control strategy, simulations were conducted using the CarSim and MATLAB/Simulink platforms. The analysis of the simulation results confirms that the proposed method effectively improves speed tracking stability and significantly enhances path tracking accuracy and overall driving stability.

To minimize the occurrence of traffic accidents, such as vehicle rear-end collisions, while enhancing vehicle following, stability, economy, and ride comfort, a hierarchical adaptive cruise control strategy for vehicles is proposed. The upper-level controller computes the desired vehicle output acceleration based on model predictive control and switches between speed and spacing control in accordance with driving conditions. The brake/throttle opening switching model, brake control inverse model, and throttle opening inverse model in the lower-level controller of ACC are designed to obtain the desired throttle opening and braking pressure of the vehicle, thereby achieving control of the vehicle. A joint simulation platform was established using PreScan, CarSim and Matlab/Simulink. Finally, simulations for three typical working conditions were conducted in Simulink to verify the performance of the adaptive cruise control strategy. The results indicate that, in both the constant-speed cruise and vehicle-following cruise conditions, the vehicle can rapidly and stably follow the set initial speed and consistently maintain a safe distance from the preceding vehicle. Under the emergency braking condition, the vehicle can promptly respond with deceleration, ensuring driving safety. The proposed control strategy can accurately and safely track the target vehicle in diverse driving conditions and can concurrently fulfill the requirements of economy and comfort during vehicle travel.

The growth of the civil aviation industry has raised concerns about the impact of airport emissions on human health and the environment. The aim of this study was to quantify the emissions of sulfur dioxide (SO2), nitrogen oxides (NOX), and carbon monoxide (CO) from in-service aircraft via open-path Fourier-transform infrared (OP-FTIR) spectroscopy at Tianjin Binhai International Airport. The results suggest that the CO and NOX emission indices (EIs) for five common aircraft/engine combinations exhibited substantial discrepancies from those reported in the International Civil Aviation Organization (ICAO) databank. Notably, during the idling, approach, and take-off phases, the CO EIs exceeded the ICAO’s standard values by (11.04 ± 10.34)%, (56.37 ± 18.54)%, and roughly 2–5 times, respectively. By contrast, the NOX EIs were below the standard values by (39.15 ± 5.80)%, (13.57 ± 3.67)%, and (21.22 ± 4.03)% in the same phases, respectively. The CO and NOX EIs increased by 31–41% and decreased by 23–24%, respectively, as the ambient temperature decreased from −3 °C to −13 °C. This was attributed to lower temperatures reducing fuel evaporation, leading to inefficient combustion and increased CO emissions and lowering the combustion temperature and pressure, resulting in reduced NOX emissions. The CO EIs had a positive correlation with humidity (adjusted R2: 0.715–0.837), while the NOX EIs were negatively correlated with humidity (adjusted R2: 0.758–0.859). This study’s findings indicate that humidity is a crucial factor impacting aircraft exhaust emissions. Overall, this research will contribute to the development of scientifically informed emission standards and enhanced environmental management practices in the aviation sector.

With the advantages of large transmission capacity, low losses, rapid and flexible power regulation, and the ability to achieve non-synchronous networking, High Voltage Direct Current transmission systems are playing an increasingly important role in long distance transmission and grid interconnection. However, under certain circumstances, such as disturbances in the DC transmission system and sudden load changes, the converter based on PI control in DC transmission system suffer from slow response speed and poor stability. In order to improve the stability of the system and the response speed of DC voltage, this paper proposes an adaptive linear active disturbance rejection control (A-LADRC) method. The method is based on the analysis of the relationship between key bandwidth parameters and output quantities in linear active disturbance rejection control and enables adaptive adjustment of the controller bandwidth parameters for fast regulation of the DC voltage and to improve the stability of the DC voltage in the event of disturbances. Finally, the proposed control method is validated by simulation, and the results show that the proposed control method can effectively improve the response speed and robustness of the DC voltage, which has good practical engineering value.

The underlying cause of commutation failures in traditional line-commutated converter (LCC) high-voltage direct-current (HVDC) transmission technology lies in the sensitivity of the thyristor devices, which are prone to turning off, thereby restoring the forward circuit breaker capability. This paper presents a coordination strategy between a controllable line-commutated converter (CLCC) and a voltage-sourced converter (VSC) and delves into the fault characteristics specific to CLCC damage. Our research focuses on CLCC topology, where fully controlled devices are incorporated to manage the thyristor’s turn-off time, ensuring its successful deactivation. This approach serves as a fundamental preventative measure against commutation faults. Furthermore, we employ a coordination strategy between the VSC and the CLCC to enhance the recovery time efficiency of the AC system. This strategy is simulated and validated using PSCAD software, and the results confirm its effectiveness in fault tolerance and AC system recovery.

The airport and its surrounding areas are home to a variety of pollution sources, and air pollution is a recognized health concern for local populated regions. Submicron particulate matter (PM1 with an aerodynamic diameter of 1 poses a great threat to human health. To comprehensively assess the source-specific health effects of PM1-bound HMs in an airport community, PM1 filter samples were collected around the Tianjin Binhai International Airport for 12 h during the daytime and nighttime, both in the spring and summer, and 10 selected HMs (V, Cr, Mn, Co, Ni, Cu, Zn, As, Cd, and Pb) were analyzed. The indicatory elements of aircraft emissions were certified as Zn and Pb, which accounted for more than 60% of the sum concentration of detected HMs. The health risks assessment showed that the total non-cancer risks (TNCRs) of PM1-bound HMs were 0.28 in the spring and 0.23 in the summer, which are lower than the safety level determined by the USEPA, and the total cancer risk (TCR) was 2.37 × 10−5 in the spring and 2.42 × 10−5 in the summer, implying that there were non-negligible cancer risks in the Tianjin Airport Community. After source apportionment with EF values and PMF model, four factors have been determined in both seasons. Consequently, the source-specific health risks were also evaluated by combining the PMF model with the health risk assessment model. For non-cancer risk, industrial sources containing high concentrations of Mn were the top contributors in both spring (50.4%) and summer (44.2%), while coal combustion with high loads of As and Cd posed the highest cancer risk in both seasons. From the perspective of health risk management, targeted management and control strategies should be adopted for industrial emissions and coal combustion in the Tianjin Airport Community.

The data from new distribution system is increasingly multi-dimensional and massive. When the distribution network participates in virtual grid division, the deep mining of distribution network data is required. In this study, a feature extraction and source–load collaborative analysis method for distribution network is proposed to master the suitability between renewable energy generation and various loads. Firstly, this method realizes raw data preprocessing through anomaly identification and reconstruction. It then uses information entropy to improve traditional piecewise aggregation approximation to reduce data dimension while considering the fluctuations of data. Finally, the method extracts the features of source–load data through spectral clustering and obtains quantitative analysis results of the matching degree between source and load through collaborative analysis. The effectiveness of the proposed method is verified by load power data and photovoltaic output data.

Objective Groundwater flow in fractured rocks has strong heterogeneity and anisotropy. The discrete fracture network (DFN) method has been internationally considered as one of the most reasonable and effective methods to describe the fracture water transport. Methods In this work, we focused on granite rock from an underground research laboratory site for the geological disposal of high-level radioactive waste. In addition, a high-performance numerical computing system and parallel codes were employed to develop a groundwater flow simulation method in fractured rocks based on the DFN model. Results The results indicated that the proposed method could conduct the groundwater flow simulation of DFN with thousands of mesh elements. This improved the computational efficiency and ability of the parallel codes to deal with complex models. We established the DFN model structure optimization and parameter setting methods of boundary conditions in a complex condition. This could ensure that the hydraulic heads were continuous at different scale models. Furthermore, in the model area, the hydraulic head is distributed as a network structure along fractures. For the connected fractures, the water level was continuous and changed from high to low. However, the water level in the nonconnected fractures was discontinuous. Groundwater flows along the fracture from the high water level area to the low water level area. The connectivity and permeability of the fracture network have an obvious influence on the groundwater flow characteristics. Conclusion Therefore, we could conclude that the parallel groundwater flow simulation method based on the DFN model could more reasonably reflect the groundwater flow in a fractured rock mass. It was of great significance to further improve the simulated prediction ability and deepen the understanding of groundwater flow characteristics in a fractured medium.

Abstract Background Hand grip strength (HGS) is a powerful indicator of sarcopenia and other adverse health outcomes. Normative values for HGS for general Chinese people with a broad age spectrum are lacking. This study aims to establish normative values of HGS and explore the correlations between HGS and body composition among unselected people aged 8–80 in China. Methods From 2012 to 2017, 39 655 participants aged 8–80 years in the China National Health Survey were included. Absolute HGS was measured using a Jamar dynamometer. The relative HGS was normalized by body mass index. Body composition indexes included body mass index, body fat percentage, muscle mass, fat mass index (FMI) and muscle mass index (MMI). Sex‐specific smoothed centile tables for the P1, P5, P25, P50, P75, P95 and P99 centiles of HGS and body composition were generated using lambda‐mu‐sigma method. The correlations between muscle strength and body composition were estimated by partial Spearman correlation analysis. Results The median values (25th and 75th percentile) of HGS in boys and girls (8–19 years old) were 22 (14, 34) kg and 18 (12, 22) kg, respectively; in men and women aged 20–80 were 39 (33, 44) kg and 24 (20, 27) kg, respectively. Values of upper and lower HGS across ages had three periods: an increase to a peak in the 20 s in men (with the 5th and 95th values of 30 and 55 kg, respectively) and 30 s in women (with the 5th and 95th values of 18 and 34 kg, respectively), preservation through midlife (20s–40 s), and then a decline after their 50 s. The lowest HGS values in both sexes were in the 70‐ to 80‐year‐old group, with the 5th and 95th percentile values of 16 and 40 kg in men, and 10 and 25 kg in women. There were substantial sex differences in body composition in the life course (all P values

With the wide application of information and communication technology in power grids, the integration and collaboration of information networks and physical grid have become an essential feature of the smart grid, constituting a typical power information physical system. However, information network has communication time delay problem, which tends to deteriorate the system controller performance or even counter-tune, leading to system instability. To effectively reduce low-frequency oscillation of the wide-area interconnected grid and overcome the negative impact of the communication network’s delay problem, a delay dependent Wide Area Damping Controller(WADC) is designed using cyber–physical power system architecture. First, we establish a power information physical system simulation platform based on Object linking and embedding for Process Control (OPC) technology, implementing the joint operation of the power system simulation tool DIgSILENT and the information system simulation tool MATLAB. The platform can effectively respond to the system’s information system and physical system interaction effects during simulation. Then, to compensate for communication delays in the power information physical system, this paper proposes a new WADC strategy that uses a Model Predictive Controller (MPC) to generate control commands and an adaptive time delay compensator to compensate for the random communication delays generated in the communication. Finally, a case study with various uncertainties and through the interference test of a four-machine system and 39 bus system, the proposed control strategy is proposed.

Abstract Background During the COVID-19 pandemic, college students were required to stay at home and maintain social distance for the entire spring semester of 2020. There is little research on how family functioning influenced mental health problems and how coping styles moderated the relationship between family functioning and mental health problems among college students during their stay-at-home period. Methods A total of 13,462 college students (age = 16–29 years) completed four online surveys between February and October 2020, namely the outbreak phase, remission phase, online study phase, and school reopening phase in Guangdong Province, China. Family functioning was assessed by the Family APGAR; coping styles were assessed by the Simplified Coping Style Questionnaire (SCSQ), depression symptoms and anxiety symptoms were evaluated by the Patient Health Questionnaire (PHQ-9) and the Generalized Anxiety Disorder Scale (GAD-7) respectively. Generalized estimating equations were used to assess associations between variables, the logit link function was used to estimate the odds ratio of different subgroups, the Newton–Raphson method was used to estimate parameters, and the Wald test was used to test the main effect and the interaction effect. Results The incidence rates of depression increased during the stay-at-home period from 33.87%, 95% CI (29.88%, 38.10%) to 40.08% 95% CI (35.76%, 44.55%) after schools reopened, χ2 = 193.68, p

The four-wheel steering distributed drive vehicle is a novel type of vehicle with independent control over the four-wheel angle and wheel torque. A method for jointly controlling the distribution of the wheel angle and torque is proposed based on this characteristic. Firstly, the two-degrees-of-freedom model and ideal reference model of four-wheel steering vehicle are established; then, the four-wheel steering controller and torque distribution controller are designed. The rear wheel angle is controlled by the feedforward controller and the feedback controller. The feedforward controller takes the side slip angle of the center of mass as the control target, and the feedback controller takes the yaw angle as the control target. Torque is controlled by two control layers, the additional yaw moment of the upper layer is calculated by the vehicle motion state and fuzzy control theory, and the lower layer distributes wheel torque through the road adhesion coefficient and wheel load. Finally, a simulation platform is established to verify the effectiveness of the proposed control algorithm.

Progesterone (PROG) and estrone (E1) are typical reproductive hormones in dairy cows. Assessing the levels of these hormones in vivo can aid in estrus identification. In the present work, the feasibility of the qualitative and quantitative detection of PROG and E1 using terahertz time-domain spectroscopy (THz-TDS) and metamaterial technology was preliminarily investigated. First, the time domain spectra, frequency domain spectra, and absorption coefficients of PROG and E1 samples were collected and analyzed. A vibration analysis was conducted using density functional theory (DFT). Subsequently, a double-ring (DR) metamaterial structure was designed and simulated using the frequency domain solution algorithm in CST Studio Suite (CST) software. This aimed to ensure that the double resonance peaks of DR were similar to the absorption peaks of PROG and E1. Finally, the response of DR to different concentrations of PROG/E1 was analyzed and quantitatively modeled. The results show that a qualitative analysis can be conducted by comparing the corresponding DR resonance peak changes in PROG and E1 samples at various concentrations. The best R2 for the PROG quantitative model was 0.9872, while for E1, it was 0.9828. This indicates that terahertz spectral–metamaterial technology for the qualitative and quantitative detection of the typical reproductive hormones PROG and E1 in dairy cows is feasible and worthy of in-depth exploration. This study provides a reference for the identification of dairy cow estrus.

Background and aim: Previous study have demonstrated that Tangshen Formula (TSF) could attenuate colonic histomorphological remodeling in the diabetic rat model induced by high fat diet plus low dosage streptozotocin (STZ). However, it is not clear whether TSF has same effect on small intestine and the effect on biomechanical properties of bowel. The aim of this study is to investigate the effect of TSF on histomorphological and biomechanical remodeling of small intestine and colon by using Zucker Diabetic Fatty (ZDF) Rat model. Materials and methods: ZDF rats (obese fa/fa) with blood glucose higher than 11.7 mmol/L were divided into ZDF group (diabetic control group) and ZDF + TSF group (TSF treatment group), the later were intragastrically administered TSF. The ZDF rats (lean fa/+) were served as normal control (ZL) group. The rats in the ZL and ZDF groups were administered with saline. The experimental period covered from 8 weeks to 24 weeks. At the end of experiment, the ileal and colonic segments were studied in vitro. The histomorphometry and biomechanical parameters were measured. Results: Compared with ZL group histomorphologically, the wet weight per unit length, wall thickness, wall area and fractions of total and type I and type III collagen in different layers for both ileum and colon increased in ZDF group. Those increasing parameters were partially inhibited in ZDF + TSF group. Compared with ZL group biomechanically, ZDF and ZDF + TSF groups had smaller opening angle and residual strain in ileum, and bigger opening angle and residual strain in colon. Whereas the wall became softer in circumferential direction and stiffer in longitudinal direction for both ileum and colon. However, no difference of biomechanical parameters was found between ZDF and ZDF + TSF groups. Conclusion: The histomorphological and biomechanical remodeling of ileum and colon were happened in ZDF rats （obese fa/fa）. TSF could partly attenuate ileal and colonic histomorphological remodeling rather than biomechanical remodeling.

The normative values of vertical jump (VJ) and sit-and-reach (SR) for Chinese people are still unclear. We aimed to determine these values and their correlations with body composition using data from China National Health Survey which included 19,269 participants aged 8–80 years. Sex-specific smoothed centile tables were generated for the P1, P5, P25, P50, P75, P95, and P99 centiles of VJ and SR using lambda-mu-sigma method. The median (Interquartile range) values of VJ and SR in males and females were as follows: 20.3 (8.8) cm and 14.1 (5.5) cm for VJ, 1.8 (11.6) cm and 6.8 (10.4) cm for SR, respectively. In males, VJ values increased to a peak around the age of 18, with the 5th and 95th values being 17.7 cm and 41.3 cm, respectively. After reaching the peak, VJ values gradually declined with age. In females, VJ values remained relatively stable from childhood to early adulthood, and then declined after the age of 30. The peak values of SR were observed in early adulthood in both sexes, and remained stable in females but declined with age in males. VJ had a negative association with body composition, particularly in females. SR was found to have a negative association with fat mass indexes in males. However, correlations in females were only marginally statistically significant. The study provides age- and sex-specific percentile reference values for VJ and SR in Chinese people and can aid in the assessment of muscle fitness and facilitate early prediction of neuromuscular disorders.

Abstract Aiming at solving the trouble that digital image information is easily intercepted and tampered during transmission, we proposed a color image encryption scheme based on alternate quantum random walk and controlled Rubik’s Cube transformation. At the first, the color image is separated into three channels: channel R, channel G and channel B. Besides, a random sequence is generated by alternate quantum walk. Then the six faces of the Rubik’s Cube are decomposed and arranged in a specific order on a two-dimensional plane, and each pixel of the image is randomly mapped to the Rubik’s Cube. The whirling of the Rubik’s Cube is controlled by a random sequence to realize image scrambling and encryption. The scrambled image acquired by Rubik’s Cube whirling and the random sequence received by alternate quantum walk are bitwise-XORed to obtain a single-channel encrypted image. Finally the three-channel image is merged to acquire the final encrypted image. The decryption procedure is the reverse procedure of the encryption procedure. The key space of this scheme is theoretically infinite. After simulation experiments, the information entropy after encryption reaches 7.999, the NPCR is 99.5978%, and the UACI is 33.4317%. The encryption scheme with high robustness and security has a excellent encryption effect which is effective to resist statistical attacks, force attacks, and other differential attacks.

The research purpose of this paper is to reveal the relationship between flood deposits, rainfall and flooding in the Loess Plateau over the last 50 years. The research in this paper is of great significance as it reveals the torrential flood events and soil erosion in the central region of the Loess Plateau. Through grading analysis and 137Cs content determination of a closed lake sedimentary profile formed by landslide-blocked rivers in middle part of Loess Plateau, Zizhou County, Shaanxi Province, the age of the sedimentary formation in the section, as well as the rainstorm events and changes of soil erosion since 1954 are studied. The results show that the sediment particle size composition in the study section is fine, mainly comprising of coarse silt, while the content of sand particles (>100 μm) is very low. The changes in137Cs content show that the sedimentary layer at a depth of 280–210 cm in the research profile was formed between 1954 and 1964, while the deep sedimentary layer at 210–70 cm was formed between 1965 and 1986 and the sedimentary layer above 70 cm depth was formed between 1987 and 2011. In total, 20 coarse particle layers (particle size >50 μm) were deposited in the lake between 1954 and 2011. The sedimentation timing of the 20 coarse particle layers was basically consistent with the timing of rainstorm events (daily rainfall ≥60 mm) in the study area, indicating that the coarse particle sediments in the lake represent rainstorm events. Soil erosion was stronger between 1954 and 1985 and was weaker after 1986.