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Aiming at the decision of energy-saving renovation scheme of public buildings, based on the comprehensive income of energy-saving and carbon trading, this paper establishes the energy-saving, carbon reduction and economic benefit models of six technologies, such as: enclosure structure ( trading, this paper established the energy-saving, carbon reduction and economic benefit models of six technologies, such as: enclosure structure ( wall and form) renovation, lighting renovation, air conditioning optimization, air-conditioning optimization, energy-saving and carbon trading. wall and form) renovation, lighting renovation, air conditioning optimization, roof PV and boiler power replacement. The decision-making method of transformation scheme under the fluctuation of energy-saving and carbon trading is as follows The decision-making method of transformation scheme under the fluctuation of electricity price and carbon trading price is constructed with the help of multiple regression algorithm. Breaking through the traditional experience empowerment evaluation model, the optimal initial investment amount and the weighting and priority of various technology selection decisions are deduced. Breaking through the traditional experience empowerment evaluation model, the optimal initial investment amount and the weighting and priority of various technology selection decisions are deduced. Finally, the effectiveness of the method is verified by combining engineering cases, aiming to provide reference for owners to Finally, the effectiveness of the method is verified by combining engineering cases, aiming to provide reference for owners to flexibly respond to the energy and carbon trading market and precise energy saving.

This experiment was aimed at verifying the 28 day oral toxicity test (GB 15193.22—2014) in accordance with the national food safety standard [11]. Rats were fed with a high amount in selenium nitrite for 28 consecutive days to observe its effect on food intake and growth of rats, and at the same time provide a basis for predicting the safety of selenium preparations consumed by the population and long-term consumption. The detection indicators included general condition, body weight, food intake, food utilization rate, and pathological examination. During the entire observation period, the animals in each dose group were generally in good condition, and no clinical symptoms related to the test substance were seen., showed a dose-dependent inhibition on the growth of body weight and food intake of male animals, especially the growth of animals in the high-dose group was significantly inhibited, and its body weight was significantly lower than that of the control group (P

The long-term vibration of the carbon canister during vehicle operation can lead to changes in its performance, thereby affecting its performance on evaporation emissions. A vibration test bench simulating vehicle vibration characteristics is used to simulate the working state of the carbon canister under actual driving conditions, analyze the amount of carbon powder precipitation and flow resistance changes in the canister after long-term operation, and compare the adsorption and desorption performance of the canister before and after aging and their effect on the evaporative emissions. The results showed that the carbon canister will produce carbon powder precipitation after being continuously subjected to the forward and backward vibration of the vehicle. This leads to a decrease in the ultimate adsorption and desorption capacity of the aged carbon canister for fuel vapor, with a more significant decrease in adsorption capacity. However, in the 2-day Diurnal Breathing Loss(DBL) test, due to the increase in flow resistance of the aged carbon canister, it is more difficult for the adsorbed fuel vapor to diffuse outward. For the unsaturated carbon canister, fuel leakage and evaporative emissions can be reduced. In evaporative emission management, it is necessary to adjust the control strategy reasonably based on the working status of the carbon canister.

To address the challenges faced by vehicles during actual operation when passing through traffic lights or intersections, where rapid changes in operating conditions can lead to a decrease in SCR efficiency and an increase in NOx emissions, this study focuses on defining characteristic position scenarios and analyzing the NOx emission characteristics of vehicles when passing through these scenarios based on real-time vehicle conditions. Through the analysis of several specific events, several road condition factors and driver behavior factors that may contribute to increased NOx emissions at characteristic position scenarios are identified. The findings indicate that when vehicles pass through traffic lights and intersections, the main causes of increased NOx emissions are low SCR temperature resulting from prolonged idling or engine shutdown, and high exhaust NOx emissions resulting from sudden excessive fuel injection. The driver behaviors associated with these situations primarily include coasting when approaching intersections, frequent stop-start behaviour due to traffic congestion or road crowding, choosing to shut off the engine for fuel efficiency during prolonged traffic congestion, and aggressive acceleration by stepping on the accelerator when the green light is about to turn red.

For the highway bridges with small or medium span, a vehicle will stay on the bridge after the excitation. So the measured values of the vibration characteristics of the bridge are related to the vehiclebridge system. In order to analyse the natural vibration characteristics of simply supported bridge and the loaded frequency of vehicle-bridge system, theoretical analysis was carried out firstly, then the simply supported beam calculation model was built based on finite element method, and the results were compared with the measured values. The finite element model of a mass block-simply supported beam system was built by regarding the vehicles as a concentrated mass block attached. Both the vibration modals of the bridge system and the loaded frequencies of the vehicle-bridge system under diffident vehicle positions were obtained by software analysing. As a result, the variation characteristics of the loaded frequency for this simply supported bridge were extracted and discussed through the comparison of the results from both finite element method and the measured.

The deviation factor of natural gas is a coefficient to quantitatively describe the deviation degree between real gas (natural gas) and ideal gas. Generally, the deviation factor of natural gas is measured in PVT cell without considering porous media. However, when natural gas is in underground porous media reservoir, due to the adsorption of porous media, the deviation factor of natural gas in porous media deviates from that measured in conventional PVT cell. Moreover, compared with other gases, CO2 has stronger adsorption capacity. Therefore, in porous media, the deviation factor of natural gas considering the adsorption of porous media is quite different from that measured in conventional PVT cell. In this paper, simulating the isothermal mining conditions in gas reservoir,the deviation factor of natural gas with different CO2 content considering the influence of porous media under different pressure isothermal conditions is studied by using the test of designed sand filled long slim tube in series. And under the same conditions, the deviation factor is compared with that of conventional PVT. The experimental results show that under the same conditions, due to the adsorption of porous media, the deviation factor measured in porous media is smaller than that measured by PVT cell without considering porous media.

With the continuous development of China's information technology, medical information is also constantly innovating, which is conducive to the diversity and effectiveness of the treatment of various diseases, including autism. Music therapy is the embodiment of the innovation of information media in medical informationization. Music therapy is a kind of information communication medium that uses music to stimulate and hypnotize people and stimulate physical reactions in various forms of music activities to promote people's physical and mental health. It is often used in the intervention research of autism. This article summarizes the effectiveness of music therapy for children with ASD in the latest research at home and abroad, and the advantages of music therapy in promoting social communication, improving attention, reducing stereotyped behavior, and improving negative emotions in children with ASD. It also reveals music How the treatment can improve the facial emotion recognition ability of children with ASD, the role of assistive robots and family participation in the music therapy of children with ASD.

Wind power forecasting is a crucial part for the safe and stable operation of wind power integration, which is under the influence of different factors such as wind speed, wind direction, atmospheric pressure. These factors bring randomness and volatility to wind power which makes it less predictable. While, there are very limited studies on describing the uncertainty of wind power. Therefore, to providing additional information on the uncertainty and volatility, a kernel-based on Gaussian Process Regression (GPR) incorporating the hyper-parameters intelligent optimization method is proposed in this paper. Firstly, the hyper-parameters solution of GPR is formulated as a nonlinear optimization with constraints. Then, an intelligent algorithm named Brain-storming optimization (BSO) is adopted to obtain the optimal hyper-parameters of GPR. Furthermore, the performance is examined on short-term wind power data. Most importantly, the GPR incorporating BSO can avoid the hyper-parameters at local optimum.

As a modern infrastructure for offshore oil and gas resources development, offshore platforms have many advantages, such as high efficiency, concentration, flexibility, and repeatability. At the same time, its upper module environment is bad, the equipment is numerous, has the very big risk. In case of fire and explosion and other accidents, it is difficult to get timely rescue. Therefore, fire risk assessment for offshore platform is very necessary. This paper focuses on the research results in the field of fire risk assessment of offshore platforms at home and abroad, points out the shortcomings of current research, and provides reference for risk reduction and effective prevention of offshore platform operations.

Based on the fabric tensor theory and the principle of least square method, the method of block processing in the same model to explore the variation of the passive earth pressure of the transversely isotropic soil was used in the study. At the same time, primary displacement application and multiple displacement application were applied to change the angle between the large principal stress direction of the filling and the normal direction of the deposition surface to obtain the new strength parameters ci and φi of each block after the model was divided and additionally analyzing the variation of the anisotropic passive earth pressure. The study shows: 1.Considering the transverse isotropy of the soil and reaching the limit equilibrium, the passive earth pressure of the soil after multiple displacement application is not only smaller than that after primary displacement application but also closed to the theoretical solution of Coulomb’s earth pressure; 2.When the soil is inclined, the anisotropy is significant when compared with the horizontal direction.

In order to suppress the leakage current of the active neutral point clamed five-level (ANPC-5L) inverter, this paper proposes a novel low common-mode voltage (CMV) modulation strategy based on the space vector modulation thought. Only the 55 voltage vectors with low CMV amplitude instead of all 125 voltage vectors are utilized. The CMV amplitude is suppressed to one-twelfth of the DC bus voltage (Vdc). In the simplified five-level space vector diagram, “obtuse triangle” synthesis principle is used to control the CMV changes twice in each carrier cycle, and get lower output current total harmonic distortion (THD). According to the vector thought, a carrier implementation method based on zero sequence voltage injection and carrier splitting is proposed. This method simplifies the calculation and is easy to implement.Simulation results prove the correctness and feasibility of this low CMV modulation strategy.

In order to enhance oil recovery in low and ultra-low permeability layer, both of the numerical simulation and physical model experiment have been researched. First, the dynamic distribution of CO1 and N1 in the oil and gas phase in the CO2-N2 compound flooding process was numerically simulated by using the long slim-tube model. The results show that the CO2 slug should have at least 0.3 PV to prevent the impact of N2 channeling effectively. Second, under the experimental conditions of complete miscibility of CO2-crude oil, the two types of natural cores including low and ultra-low permeability, respectively, are used for experimental study on oil displacement. The results confirm that CO2-N2 compound flooding with 0.3 PV CO2 pre-slug can achieve a good result. Finally, a five-point well pattern element model is established by CMG. The recovery and the gas cost of per ton of oil are calculated respectively for CO2-N2 compound flooding and full CO2 flooding at 300 m well spacing of low and ultra-low permeability layer. According to the simulation results, the optimal CO2 pre-slug size in CO2-N2 compound flooding under the condition of low and ultra-low permeability layer five-point well pattern is 0.4 PV.

The content and the transmission characteristics of the water in the polymer electrolyte membrane fuel cell (PEMFC) have a significant influence on its performance. So far, there are few separate numerical studies on the process of water transport in the bionic flow channel, and the performance of bionic flow channel is different from conventional flow channel in part owing to the differences of their water drainage. Therefore, in order to understand the water drainage process of bionic flow channel, two different types of bionic flow channels are adopted in this paper. The method of numerical simulation is used to study the transmission process of liquid water in the bionic flow channel of different placement orientations. The simulation results found that the orientations of bionic flow channel has an influence on the process of water transport in the flow channel, and the process of water drainage also has a significant difference in the two different types of bionic flow channel.

In order to provide reference for the engineering design in the area with large wind, water flow and other horizontal loads, the experimental study on the horizontal bearing capacity of composite foundation under three different working conditions was carried out in this paper, which includes cap-single pile, cap-9 piles and enlarged cap-9 piles. The results show that under the condition of cap-9 piles, the group pile effect coefficient is 1.17, and the load sharing ratio of the back piles is the largest, and the middle and front piless decrease sequentially. Also, with the increase of horizontal load, the load sharing ratio of the back pile increases while the middle and front piless is decremented. Under the condition of enlarged cap-9 piles, the group pile effect coefficient is 1.36, which is 16.24% higher than that of the cap-9 piles, which means the horizontal resistance is obviously enhanced. At the same time, compared with the cap-9 piles, the load sharing ratio of the back pile is reduced while the middle and front piless is increased, which means the stress of pile body tends to be more uniform.

Taking the ground settlement while pipe-jacking construction in soft soil as the engineering background, the effect of pipe jacking were studied by numerical simulation. It focused on the factors that mainly influenced surface settlement of ground including in-situ stress release rate (or ground loss ratio), chamber pressure, elastic modulus of soil, buried depth and diameter of pipe. That would provide theoretical basis for taking measures to reduce surface subsidence while jacking. The main conclusions were as follows: (1) The in-situ stress release rate and pipe diameter were proportional to the surface subsidence. (2) Chamber pressure, elastic modulus and buried depth were inverse proportional to the surface subsidence. (3) From the point of view of the influence on surface settlement, the sensitivity of pipe diameter and elastic modulus of soil was the greatest, followed by burial depth and chamber pressure, and the stress release rate was the smallest.

With the continuous improvement of marine strategic status, the degree of emphasis on marine environmental security incidents has increased. In order to effectively prevent and manage marine environmental events, we need to work through risk assessments to prevent the occurrence of events or reduce the impact of events. Based on the theory of public safety triangle, this paper studies and analyzes the comprehensive risk assessment of marine environmental safety. Based on the historical disaster situation investigation and the existing disaster risk assessment research results, a comprehensive risk assessment framework was established. According to the development process of the marine environmental safety incident and the influence of the incident, the comprehensive risk evaluation index system is constructed from three aspects: event risk, disaster tolerance and emergency management. According to the expert experience and judgment matrix, considering the acceptable level of risk, the risk assessment grading standard is established, which provides theoretical support for the comprehensive risk assessment of marine environmental safety.

Based on the remote sensing and GIS techniques, the relationships of the variables influencing the snowmelt flood such as the snow area, the snow depth, the air temperature, the precipitation, the land topography and land covers are analyzed and a prediction and damage assessment model for snowmelt floods is developed. This model analyzes and predicts the flood submerging range, flood depth, flood grade, and the damages of different underlying surfaces in the study area in a given time period based on the estimation of snowmelt amount, the snowmelt runoff, the direction and velocity of the flood. Then it was used to predict a snowmelt flood event in the Ertis River Basin in northern Xinjiang, China, during March and June, 2017 and to assess its damages including the damages of roads, transmission lines, settlements caused by the floods and the possible landslides using the hydrological and meteorological data, snow parameter data, DEM data and land use data. A comparison was made between the prediction results from this model and flood measurement and its disaster loss data, which suggests that this model performs well in predicting the strength and impact area of snowmelt flood and its damage assessment.

Particle swarm optimization(PSO) algorithm has been widely applied in solving multi-objective optimization problems(MOPs) since it was proposed. However, PSO algorithms updated the velocity of each particle using a single search strategy, which may be difficult to obtain approximate Pareto front for complex MOPs. In this paper, inspired by the theory of P system, a multi-objective particle swarm optimization (PSO) algorithm based on the framework of membrane system(PMOPSO) is proposed to solve MOPs. According to the hierarchical structure, objects and rules of P system, the PSO approach is used in elementary membranes to execute multiple search strategy. And non-dominated sorting and crowding distance is used in skin membrane for improving speed of convergence and maintaining population diversity by evolutionary rules. Compared with other multi-objective optimization algorithm including MOPSO, dMOPSO, SMPSO, MMOPSO, MOEA/D, SPEA2, PESA2, NSGAII on a benchmark series function, the experimental results indicate that the proposed algorithm is not only feasible and effective but also have a better convergence to true Pareto front.

With the arrival of large data age, distributed database HBase becomes an important tool for storing data in massive data age. The normal operation of HBase database is an important guarantee to ensure the security of data storage. Therefore designing a reasonable HBase monitoring system is of great significance in practice. In this article, we introduce the solution, which contains the performance monitoring and fault alarm function module, to meet a certain operator’s demand of HBase monitoring database in their actual production projects. We designed a monitoring system which consists of a flexible and extensible monitoring agent, a monitoring server based on SSM architecture, and a concise monitoring display layer. Moreover, in order to deal with the problem that pages renders too slow in the actual operation process, we present a solution: reducing the SQL query. It has been proved that reducing SQL query can effectively improve system performance and user experience. The system work well in monitoring the status of HBase database, flexibly extending the monitoring index, and issuing a warning when a fault occurs, so that it is able to improve the working efficiency of the administrator, and ensure the smooth operation of the project.

An ultrasonic elliptical vibration assisted chemical mechanical polishing(UEV-CMP) is employed to achieve high material removal rate and high surface quality in the finishing of hard and brittle materials such as monocrystalline silicon, which combines the functions of conventional CMP and ultrasonic machining. In theultrasonic elliptical vibration aided chemical mechanical polishingexperimental setup developed by ourselves, the workpiece attached at the end of horn can vibrate simultaneously in both horizontal and vertical directions. Polishing experiments are carried out involving monocrystalline silicon to confirm the performance of the proposed UEV-CMP. The experimental results reveal that the ultrasonic elliptical vibration can increase significantly the material removal rate and reduce dramatically the surface roughness of monocrystalline silicon. It is found that the removal rate of monocrystalline silicon polished by UEV-CMP is increased by approximately 110% relative to that of conventional CMP because a passive layer on the monocrystalline silicon surface, formed by the chemical action of the polishing slurry, will be removed not only by the mechanical action of CMP but also by ultrasonic vibration action. It indicates that the high efficiency and high quality CMP of monocrystalline silicon can be performed with the proposed UEV-CMP technique.