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Chromium from industrial wastewater, waste, pesticides, fertilizers, etc., always causes serious environmental problems. High levels of chromium pollution can have adverse effects on environments and living organisms. In this study, titanium salt was used to react with green tea extract to form a composite material, and the material was further used to remove hexavalent chromium in solution. The removal effect of hexavalent chromium was investigated under different reaction conditions, namely temperature, time, pH, and initial chromium concentration. The results showed that the chromium removal effect was the best under the conditions of acid to neutral pH, 45℃, reaction time of 24 h, and initial chromium concentration of 80 mg/L. This study provides a feasible method to solve the problem of chromium pollution and has high application value in wastewater treatment.

Many concrete structures in use have safety problems due to material deterioration, actual construction defects, structural damage, etc. Therefore, nondestructive testing is required to determine the presence of defects. Ultrasonic technology is an important tool in nondestructive testing, which can detect defects in concrete and be combined with other methods or models to make it more accurate. At present, ultrasonic inspection technology has been more research at home and abroad, both in theory and in engineering, and there has been great progress. This paper summarizes the latest progress of ultrasonic inspection technology for concrete structures at home and abroad respectively, and points out the future development trend.

Making a high dimensional (e.g., 100k-dim) feature for hyperspectral image classification seems not a good idea because it will bring difficulties on consequent training, computation, and storage. In this paper, we study the performance of a high-dimensional feature by texture feature. The texture feature based on multi-local binary pattern descriptor, can achieve significant improvements over both its tradition version and the one we proposed in our previous work. We also make the high-dimensional feature practical, we employ the PCA method for dimension reduction and support vector machine for hyperspectral image classification. The two real hyperspectral image datasets are employed. Our experimental results with real hyperspectral images indicate that the high dimensional feature can enhance the classification accuracy than some low dimensional.

Against the backdrop of increasing integration of the global economy, supply chain finance faces challenges such as information silos, high cost of paper document transmission, and difficulty in risk control. This study focuses on the application of blockchain technology in enhancing the transparency of sustainable procurement for enterprises. Through an indepth analysis of successful cases such as the FILO platform and Walmart, the study reveals how blockchain technology can effectively solve the problem of information asymmetry in the traditional procurement process and improve the transparency and efficiency of procurement through its decentralization, data inerrancy, and traceability throughout the process. The study explores the potential value of blockchain technology in the field of supply chain finance using case study and model construction. The results show that blockchain technology can significantly optimize the procurement management process, reduce the risk of human intervention, promote collaborative supply chain operations, and enhance consumer trust. In addition, the study also looks forward to the future trend of the integration and application of blockchain with artificial intelligence, big data and other technologies, and puts forward relevant policy recommendations and practical insights, which provides a reference path for enterprises to implement blockchain technology to enhance procurement transparency.

With the implementation of China’s “Carbon Peaking and Carbon Neutrality Goals” policy, the efficient utilization technology of green energy such as solar energy has been further promoted and popularized. However, research on PSDF (Photovoltaic, Storage, Direct-Current, Flexibility) buildings is still in the demonstration construction stage, and there is still limited research on its application in the heating system of flue-cured tobacco room. This paper discusses the photovoltaic energy scenarios in Chongqing area and reviews the progress of research on solar energy-assisted heating systems in flue-cured tobacco production. It analyses the transient changes in the thermal-humidity load of the flue-cured tobacco room. Based on the direct proportionality of thermal-humidity load and heating equipment power, it provides flexibility indicators for measuring the flexible power system of the flue-cured tobacco room. Furthermore, it proposes technical measures for energy saving and carbon reduction in flue-cured tobacco room, providing a technical route for the early realization of low-carbon flue-cured tobacco.

Flight safety reports from different sources indicate that the proportion of accidents caused by flight fatigue accounts for 6-11% of all types of flight accidents. Current regulations in the civil aviation industry across the world generally emphasize the length of working hours rather than the influences of circadian rhythm disorders. Based on an analysis of the flight mission data of 567 pilots in 2019, which highlighted the associations between circadian rhythm disorders and flight fatigue, we have proposed a new algorithm to reflect pilots’ fatigue status to include five main indicators: actual working hours, circadian rhythm disorders, work rhythm disorder, altitude flight hours and flight crew composition. The results assessed by the new algorithm reported that about 70% of the airline pilots studied were under the threat of a high risk of fatigue in 2019. Subsequently, this research suggests the use of two algorithms to optimize pilot scheduling systems, and findings show that the percentage of pilots with a high level of fatigue can be largely reduced.

The subjective and objective thermal comfort evaluations of adults and preschoolers in radiant floor heating rooms in a hot-summer and cold-winter area are tested in this article, and the thermal response of the two groups of subjects are analysed using a differential analysis method. The thermal response characteristics of subjects wearing winter clothing with a thermal resistance of 1.02 clo and maintaining a sitting posture were studied at different locations in the office building and different indoor temperatures by combining the characteristics of hot-summer and cold-winter area and the characteristics of office buildings. The results show that when the indoor temperature varies, there was a significant difference in the local skin temperature of the calf of the two groups of subjects (P

Depression, as one of the largest influence disorders, needs more attention on its growing patients. Medicine treatment has been seeing as the major treatment for depression. As one of the most commonly used medicine, Selective Serotonin Reuptake Inhibitors (SSRIS) increases serotonin levels to treat depression effectively, and the data from clinical data prove its value. Furthermore, Serotonin and Norepinephrine Reuptake Inhibitors (SNRIs) and Monoamine Oxidase Inhibitors (MAOIs) treat depression by affecting at least one neurotransmitter, generally is chemical in the brain and digestive system. Other therapies were mostly as an auxiliary, such as psychological therapy, Electroconvulsive Therapy (ECT), Transcranial Magnetic Stimulation (TMS), and Vagus Nerve Stimulation (VNS). These therapies often work effectively by stimulating neurotransmitters’ activity and increasing the activeness of the reward system. After new study and technology production, new development like ketamine can satisfy Individual Differences by more detailed inspection. Optogenetics in auxiliary treatment can be another way to increase the exactness of ECT and VNS after solving problems such as actual circuits in the whole network. In this review, we first focus mostly on drug treatments. We then summarize current information for other treatments and discuss the mechanisms that lead to in effect. Ultimately, we predict future development in the drug and optogenetics area. The previous study on depression treatment leads us a way to discover a future solution.

Polylactic acid (PLA) is one of the most extensively studied biodegradable materials. PLA is a versatile material with excellent bio-compatibility, bioabsorbability, biodegradability, and low toxicity. As an environmentally friendly polymer, PLA is favored by researchers and has explored many commercial applications, playing an important role in medicine and industry to replace many traditional petrochemical-based polymers. However, the strength and mechanical properties of PLA need to be improved to meet the practical application of multiple scenarios. The purpose of this review is to explore the modification methods of grafted copolymerization and block co-polymerization to improve the performance of PLA. This review also focuses on the medical applications and covers some non-medical applications of PLA.

In this paper, a prefabricated structure is used to study the main transformer firewall with truss structure of the substation. The beams, columns and wall panels of the firewall are prefabricated components, and the cast-in-place structure is used only at the top beam and column joints.

In this paper, through the application of 3D design technology in the construction of 220kV Miluoxi substation, the main aspects of the application of 3D design technology in the construction are summarized, including inter discipline verification, collision inspection, real scene modeling, equipment 3D installation details, 4D construction simulation, VR technology application and mobile application solutions. This paper also summarizes the economic, management and social benefits of three-dimensional application, which can be used as a reference for the following projects.

Permanent magnet synchronous generators (PMSGs) with full converters have been widely used in wind power generation due to its superior flexibility and controllability. However, under some circumstance, the oscillation modes of PMSG (POMs) may excite strong resonance with the electromechanical oscillation modes (EOMs) of the power system that degrades the power system small signal stability. In this paper, A two-open-loop subsystem model is firstly derived to analyze the oscillation modes. Then the POMs are investigated with modal analysis, the relationship between POMs and related controllers are clarified. On this basis, the strong resonance between PMSG and the external power system is revealed and identified. Furthermore, a five-step parameter tuning method is proposed to relocate the position of POM as well as suppress the strong resonance. Both modal analysis and time-domain simulations validate the effectiveness of the proposed method.

In this paper, for the UAV attitude angle stabilization system under constant flat wind disturbance, the fuzzy adaptive PID control theory is used to establish the equation of wind disturbance attitude angle stability system. After mastering the control rate of the system, the fuzzy controller is designed by using matlab, and the attitude angle dynamic simulation analysis was carried out. The results show that under the interference of flat wind, the longitudinal attitude of the UAV is changed by interference, and the fuzzy adaptive PD is used to control the attitude angle of the aircraft, which has faster tracking performance, smaller adjustment time than the traditional PD control. Thereby achieving better maneuverability and less steady-state error. Therefore, the fuzzy adaptive PD can better control the attitude stability of the UAV, improve the wind resistance of the UAV, and ensure the flight is safe and reliable.

For the hypersonic vehicle nonlinear attitude mode in reentry process with a strong coupling, aerodynamic parameter perturbations and non-deterministic, combine extended state observer and nonlinear law state error feedback, design the hypersonic vehicle MIMO-ESO ADRC attitude controller. Put interference such as uncertainty, coupling and parameter perturbations as “the sum of interference” ,use the extended state observer to estimate and dynamic feedback compensation, use nonlinear law state error feedback to inhibit residual of compensation. ADRC controller is charged without a precise model of vehicle , and without precise perturbation boundaries of aerodynamic parameters.Simulation results show that the MIMO-ESO ADRC attitude controller can overcome the impact of large-scale perturbations of interference and aerodynamic parameters, have good dynamic qualities and tracking capabilities, also have strong robustness.

Ad Hoc network is a kind of wireless mobile network that does not depend on any fixed infrastructure. It has the characteristics of no center, self-organization, and high dynamic and limited energy. Therefore, Ad Hoc network has security risks. The Ad Hoc secure routing based on the trust model and the reference node strategy provides a secure environment for the establishment of communication routing. The AODV routing protocol is improved. The protocol selects a trusted communication node to establish routing according to the comprehensive evaluation result of the trust model, and finds out the data message discarding the attack node by the trust model. At the same time, the reference node strategy is proposed to defend the black hole attack node. Theoretical analysis and simulation results show that the proposed secure routing scheme can effectively detect and isolate malicious nodes, resist black hole attack and data packet attack attacks, and has high security characteristics.

With the widespread application of location-based services, users 'privacy concerns have become the focus of users' attention. Based on the k-anonymity method and the SpaceTwist algorithm, this paper proposes a method of incremental inquiry user privacy protection. The method preliminarily anonymizes the user's location information and points of interest on the client side, On the anonymous server side, combining the road network environment with the latitude and longitude grid generates the minimum anonymous area of random loop, instead of the user initiating incremental inquiry to the location service provider, Anonymous zones ensure k-anonymity for mobile users and road information to protect user privacy. Security and experimental analysis show that this scheme can improve the effectiveness of user query service while meeting the privacy requirements of users.

Since 1954, the Soil Conservation Curve Number (SCS-CN) method is widely applied in hydrological field to predict the direct runoff resulting from event rainfall. Originally, the lambda value was fixed at 0.2. However, based on recent studies, the simplied SCS-CN method was unable to predict a consistent and accurate runoff amount. Most of the research studies in various countries claimed that lambda value was a variable and most likely should be less than 0.2. Most of the researchers applied either mean or median λ value directly without checking the statistics. Misuse of lambda value in SCS-CN model will lead to inconsistent runoff estimation. Moreover, although λ value can be determined, the equivalent CN0.2 cannot be found. Some of research studies or even Hydrology Textbook substitute Sλ directly into CN equation and lead to wrong CN calculation. In this study, the statistical significant λ value and regional specific S correlation are developed under the guide of non-parametric inferential statistics. by using bootstrapping, Bias corrected and accelerated (BCa) technique with 2000 samples.

In the past, the CN was determined through SCS handbook. In order to determine runoff prediction using SCS-CN model, selection of CN is important. However, the conventional CN methodology with inappropriate CN selection often produces inconsistent runoff estimation. Thus, the new direct curve number derivation technique based on rainfall-runoff datasets with supervised numerical optimization technique under the guide of inferential statistics was developed to improve the accuracy of surface runoff prediction. Furthermore, the two decimal point CN system was proposed in this study. The optimum CN of Melana site is 90.45 at alpha 0.01 with BCa 99 % confidence interval range from 90.45 to 95.12. The regional specific calibrated SCS-CN model with two decimal point CN derivation technique is out-performed the runoff prediction of conventional SCS-CN model and the asymptotic curve number fitting method.

This paper shows a wind tunnel test bed with parallelogram structure. The three-dimensional model was built by Solidworks after analyzing the movement principle. Then the model was imported to Workbench and carried out modal analysis according to the theory of finite element modal analysis. Finally the first six vibration mode and the natural frequency were got. This result provides theoretical support for the further research of the stability of the structure, and it also provides theoretical basis for the optimal design of the institution.