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In the process of modern English teaching, teachers should not only explain the basic English theory to students, but also expand the teaching contents according to the students'training requirements, provide support for students to acquire richer knowledge content. In developing situational English teaching, we should make full use of the advantages of multimedia information technology in order to help students master all kinds of English knowledge and skills and understand the English application scene effectively, through the reconstruction of English classroom, the ideal effect of English teaching wisdom innovation can be realized. This paper analyzes the background of the application of multimedia information technology in modern English situational teaching, and puts forward some concrete application strategies.

Single-layer special-shaped folded-plane latticed shell had been applied in Shenyang culture and art center. In order to analysis its static stability, explore the form of buckling modes and find out its critical load factor, this paper analysis the optimized structure with MIDAS Gen. Eigenvalue buckling analysis and nonlinear buckling analysis showed that the in-plane stiffness of the structure is very large, and the out-plane stiffness is small, the upside structure is prone to instability. The critical load factor for this structure is 10.32, the structural overall stability is fine according to the code. This structures is sensitive to the initial geometric imperfections which could lower structural stability of the system.

Firstly, it introduces the current situation of talent training mode of economics major in the context of integration production and education. Then, it analyses the current situation and the cause of the problem of the cultivation mode of economic professionals in colleges and universities. Finally, the cultivation mode of economic professionals in colleges and universities under the background of industry and education integration is constructed.

The problem of bottom hole effusion is an important reason for the reduction and even shutdown of natural gas wells. Downward velocity string is an important drainage gas recovery process, which can improve the flow rate of gas and discharge more liquid from the wellhead. However, the depth and timing of the velocity string is a technical problem that has been difficult to solve by field engineers. To solve this problem, this paper designs a method to select the depth and timing of the velocity string in the case of highly deviated wells and applies this method to Well X6–2 and Well X2–1 of PCOC in Ordos Basin, China. The optimization results show that when the wellhead pressure is 6.26 MPa, Well X6–2 should lower the 2–1.71 in. or 2.375–1.995 in. velocity string to 3337.9 m before the formation pressure decays to 8.800 MPa, which is most conducive to improve the liquid carrying capacity of gas wells. When the wellhead pressure is 4 MPa, Well X2–1 should lower 2–1.71in. velocity string to 3401.3 m before the formation pressure decays to 5.800 MPa, or lower 2.375–1.995 in. velocity string to 3401.3 m before the formation pressure decays to 5.900 MPa.

The characteristics of four kinds of sludge obtained from different drinking water treatment plants in Australia and China were contrastively analyzed in this study using x-ray fluorescence, scanning electron microscopy, and x-ray diffraction. The conducted SAI test determined the pozzolanic reactivity of drinking water sludge ash (DWSA), which was derived from the grinding and calcination of drinking water treatment sludge (DWTS). The results indicated that the Al2O3 and SiO2 were the main components of DWTS, and the main crystalline minerals in DWTS were quartz, kaolinite, and aluminum sulfate hydroxide hydrate, which can be transformed into the reactive amorphous state after calcination at 800 ºC. Also, the SAI index of DWSA-derived mortar samples met the requirement, indicating a satisfying pozzolanic reactivity. Therefore, the DWTA was possible to be recycled as a pozzolan in cement-based materials.

Due to the specific natural conditions and high intensity of human activities in Shenzhen, the characteristics of water and soil erosion of Shenzhen are prone and frequent. There are no large rivers, lakes and reservoirs in Shenzhen, and the rainwater storage capacity is unsubstantial that result in some problems such as ecological environment deterioration, river siltation, drainage pipe network blockage, and aggravation of flood disasters. The work of soil and water conservation in Shenzhen is still grim. In this paper, the sediment under different soil and water conservation measures were measured based on long-term observation of typical road engineering, river engineering and pipeline engineering in Shenzhen. Then, the effect of soil and water conservation measures implemented in these typical engineering were analyzed. At last, the optimal proposals of soil and water conservation measures for these typical engineering were proposed. This research aims to provide data support for the formulation and modification of soil and water conservation technical specifications for production and construction projects in Shenzhen.

DNA is used as self-nanomaterials to assemble into specific structures. DNA tile provides a new idea for the application of DNA tile in the field of computing. Recent years, Queue and Stack are important linear data structures which are used in various software systems widely. The implementation of DNA based queue and stack has been studied continuously for many years. In the traditional DNA computing, queue and stack are mostly realized by DNA strands displacement, restriction endonuclease and ligase were used. However, as an active material, it has a high requirement for enzyme experimental conditions. The purpose of this paper is to implement queue and stack structures using non-enzyme systems. The rule of Queue is characterized by FIFO (first in first out), which allows for insertion at one end of the list and deletion at the other. The rule of Stack is characterized by FILO(first in last out), which allows for insertion and deletion at one end of the list. We are aimed to implement Queue and Stack using self-assembly and disassembly via DNA Tiles. No enzymes are needed for the whole experiment. As an enzyme-free system, it provides a new method to implement stack and queue.

For the power distribution network line loss calculation, there are some problems, such as backward method, long calculation period, large workload and poor real-time performance. To this end, this paper proposes a real-time calculation method for distribution line loss based on dynamic three-phase unbalance, and a hardware device system with unbalanced phase sequence identification function, three-phase unbalance detection function and line loss real-time calculation function has been developed. The system uses a master-slave design based on the principle of wireless transmission. The slave collects standard three-phase current signals and transmits them to the host through wireless transmission. The host is installed on the low voltage side of the transformer in the transformer region, and the current signal of the transformer region is collected in real time. Unbalanced phase sequence identification, unbalance calculation, and line loss calculation based on dynamic unbalance are performed by comparing the current signals collected by the master and the slave. The above algorithm implementation process can be displayed online in real time. In addition to the core data processing and waveform display functions, the device also includes a battery power supply and management system, a signal storage and transmission system, and temperature measurement, and overcurrent and overvoltage protection. The test results of the device show that the device has the characteristics of convenient carrying, fast detection of three-phase unbalance, and accurate calculation of line loss. The device can monitor the running status of the distribution network transformer region in real time.

The dead pig is an organic waste rich in oil and protein, and is an ideal anaerobic digestion raw material. This study based on single factor ANOVA and Modified Gompertz model. It investigated the effects of the ratio of dead pigs on biogas production by middle temperature co-digestion of pig manure and dead pigs. And the biogas production potential was determined. The results showed that there was no significant correlation between the ratio of dead pigs and the biogas production. The ratio would significantly affect the average methane content and degradation rate. When the addition ratio was in the range of 3 to 15%, the biogas production was between 191.39 and 202.44 (L/kg VS). The average contents of methane were 50.67%, 50.35%, 41.83%, 45.53% and 44.57%, respectively. The time required to reach 80% of the biogas production was 28, 34, 36, 65 and 63 days, respectively. The degradation rate of the raw materials was generally decreased with the increase of the addition ratio. The results of Modified Gompertz model fitting showed that the mixed raw materials had a fully anaerobic digestion with high utilization rate and short hysteresis in the range of 0 ~ 9%. Therefore, a hydraulic retention time (HRT) of 30 days and the addition ratio was in the range of 0 to 6% could be recommended for a continuous digester. It could get a better gas production and higher raw material utilization.

For analyzing partial discharge ultrasonic wave characteristic on typical defects in SF6 gas insulation switchgear (GIS), a 110 kV GIS was taken as an object to design and simulate the typical partial discharge models in GIS. There are point electrode model on bus and cavity of GIS, floating electrode model, air interstice model in insulator, metal particle and iron core electromagnetic shock models. PD signals on different defects were thus detected with the ultrasonic method. The experimental results indicated that the ultrasonic signals of different defects showed different characteristics in waveform, amplitude and phase resolved partial discharge chart, which is helpful in PD pattern recognition for GIS.

The paper designed a semicircle dipole inner sensor for UHF partial discharge detection in GIS. By comparing the symmetric semicircle dipole sensor and asymmetric semicircle dipole sensor characteristics, the symmetric semicircle dipole sensor’s coupling property is better than that of asymmetric semicircle dipole sensor. At the same time, by changing the symmetric semicircle dipole transducer radius, the position of the feeder pole , the height of the feeder pole, analyze its influence on sensor features.

A multi-body dynamics simulation model of CJ20-25 AC contactor was established with Pro/E（Pro/Engineer)in this paper. A coupling simulation with machine, electric, magnetic on the contactor has been achieved in this model. Dynamic parameters which were called use the secondary development technology of ADAMS. The dynamic contact pressure signal of an AC contactor was obtained with ADAMS’s own simultaneous solution such as electromagnetic suction, kinematics and dynamics equations. The simulation results and actual measurement of contactor contact pressure signals are very similar. However, the complexity of the measured contacts vibration is greater than the simulation results because the actual working condition is more complex. This result provides a theoretical foundation to the dynamic contacts contact pressure test.

As an important part of modern integrated transportation system, urban rail transit generates carbon emissions mainly by consuming electric energy. Aiming at the problems such as single index and weak accuracy of the current carbon emissions accounting method for urban rail transit, this study builds a refined carbon emissions calculation model based on existing industry standards and norms, puts forward refined carbon emissions calculation factors under different conditions, and designs efficient algorithms to solve them. The research hopes to provide a basis for differentiated policy formulation for urban rail transit operators, so as to facilitate urban rail transit operators to obtain more say in carbon trading, complete carbon quotas more scientifically and rationally, and better help urban rail transit enterprises to complete the strategic goal of "carbon neutrality" and "carbon peak".

This article explores the ideological and educational functions contained in high-level language programming. It attempts to closely integrate knowledge transfer and ideological education based on the application of teaching practice cases, in order to explore the new “integrated” pattern of full course education in new engineering and the resource utilization ecosystem based on case libraries.

The dual carbon goals is a significant strategy made by Chinese government to promote the initiative of the community with a shared future for humanity and achieve environmental sustainable development. To fulfill this mission, Chinese universities actively integrate the dual carbon goals into various disciplinary subjects, which is considered a crucial responsibility. Among them, the English general courses also bear the responsibility of nurturing environmental awareness and global responsibility of students. This article aims to explore reforms of English general education under the dual carbon goals, focusing on curriculum material revision, instructional process design, the cultivation of practical skills, the integration of research and teaching, and the development of teaching teams. Positive teaching outcomes have been yielded, and the teaching model of “integrating the dual carbon goals with competition-based learning” has been obtained, providing guidance and reference for the reform of general education courses in universities.

Coal spontaneous combustion is one of the main disasters that threaten mine safety production., and coal adsorption characteristics is the main cause of coal spontaneous combustion. Therefore, a lot of researchers have begun to pay close attention to the field of coal adsorption research to prevent coal spontaneous combustion. Based on bibliometrics, this paper analyzes the number of published papers, journal sources, high-yield authors, institutions and research hotspots on coal adsorption in the SCI database of Web of Science platform, and makes a visual analysis using Citespace software. The research shows that the number of papers published in the field has been on the rise in recent years, and China’s influence in this field has gradually strengthened. The most in-depth research institutions and journals in the field of coal adsorption are China University of Mining and Technology and FUEL, respectively. In terms of research content, the coal pore structure and multi-factor coupling affect on coal adsorption capacity will be a research hotspot in this field in the future.

The supercritical CO2 Brayton cycle integrated with a solar power tower system has the advantages of high efficiency, compact cycle structure, strong scalability, and great power generation potential, which can positively deal with the energy crisis and global warming. The selection and optimization of design points are very important for actual operating situations. In this paper, the thermodynamic and economic models of the 10 MWe supercritical CO2 Brayton cycle for application in solar power tower system are established. Multi-objective optimizations of the simple recuperative cycle, reheating cycle, and recompression cycle at different compressor inlet temperature are completed. The thermal efficiency and the levelized energy cost are selected as the fitness functions. The ranges of the optimal compressor inlet pressure and reheating pressure on the Pareto frontier are analyzed. Finally, multiobjective optimizations and analysis of the supercritical CO2 Brayton cycle at different ambient temperature are carried out. This paper investigates the influence of the compressor inlet temperature and ambient temperature on the thermal efficiency and economic performance of the supercritical CO2 Brayton cycle.

Plastic has brought great convenience to people’s lives, but it has also brought severe environmental pollution to the world. It is almost impossible to break down entirely in nature, and plastic waste, whether in rivers, oceans, or on land, can persist in the environment for centuries. The problem of plastic waste disposal has caused worldwide concern. It is necessary to reduce the production of plastic products through global cooperation effectively. However, achieving this goal will also involve some unexpected issues, such as controlling the adverse economic impact of plastics, and the rationality and fairness of the distribution of responsibilities between different countries. This paper collects massive data and takes China as an example to study the impact of plastic output reduction on China’s Express industry and the plastics manufacturing industry using multivariate regression. This paper summarizes the positive and negative effects of plastic waste reduction. Given the distribution and management of national and regional plastic waste responsibilities, the global carbon emission rights distribution method is used for reference. The comprehensive index allocation method is used to deal with the problem of both fairness and efficiency relatively. What is more, based on the conclusions, this paper also provides suggestions for a global joint response to plastic waste.

After the carbon neutral target is proposed, China’s new energy will usher in a leapfrog development, and its volatility and randomness put forward higher requirements for the flexibility of the power system. Energy storage has strong flexible adjustment capabilities. With the continuous improvement of technology and economy in recent years, it has been promoted and applied in all aspects of the power system, and its value in improving system flexibility is gradually reflected. This paper satisfy the power balance system and new energy given perspective, aiming at the lowest cost of power supply, regional energy storage size optimization model is put forward, with a actual regional power grid as an example, has carried out empirical research, quantitative analysis of correlation between the development of new energy and energy storage scale and verify the model is scientific and accurate.

In order to screen out the plants used to repair heavy metal pollution in the soil, five plants and surface soil were collected in the Huize lead-zinc mine area, centered on the hyperaccumulator plant Arabis alpina L. var. parviflora Franch, measured the heavy metal content of in shoot and root of plant and surface soil, and analyzed the characteristics of heavy metal accumulation in plants. The results showed that the soil Cd pollution in the Huize lead-zinc mining area was the most serious; among the five plants, the Cd bioconcentration factor(BCF) and translocation factor(TF) of A. alpina were more than 1, and the TF of Pb was more than 1; the TF of Anaphalis margaritacea, Cyananthus inflatus and Arenaria orbiculata to Cu and Zn were more than 1, the TF of Juncus effusus to Cd and Zn were more than 1. These five plants had good tolerance to heavy metals and were of great significance to the remediation and restoration of heavy metal contaminated soil in lead-zinc mining areas.

The concept of pro-environmental behaviour in low carbon consumption has increasingly attracted academics’ attention in the last two decades. There has been a growing interest in exploring the association between people’s travel attitude and behaviour. This study has critically reviewed, compared, and discussed some of the key theories around these research topics. However, based on the findings of the literature review, there is a dearth of research examining the association between people’s travel attitude and their actual behaviour. Therefore, this study seeks to fill the gap by examining the causal linkage between people’s attitude towards a specific travel mode and their actual travel behaviour.

To explore the effects of Cd and As composite contaminated soils on the element contents and effectiveness in rhizosphere soils of different forages, the root morphology, rhizosphere soil elements and their availability of 21 forages were studied and analyzed. The results showed: The 21 cultivars showed significant differences in root morphological characteristics. Root length is an index of root morphology that has the highest correlation with other elements and availability. And the correlation between the availability of each element and root morphology was higher than that of element content. Among them, Fe availability was significantly correlated with root morphological characteristics (P

Current underwater shipwreck side scan sonar samples are few and difficult to label. With small sample sizes, their image recognition accuracy with a convolutional neural network model is low. In this study, we proposed an image recognition method for shipwreck side scan sonar that combines transfer learning with deep learning. In the non-transfer learning, shipwreck sonar sample data were used to train the network, and the results were saved as the control group. The weakly correlated data were applied to train the network, then the network parameters were transferred to the new network, and then the shipwreck sonar data was used for training. These steps were repeated using strongly correlated data. Experiments were carried out on Lenet-5, AlexNet, GoogLeNet, ResNet and VGG networks. Without transfer learning, the highest accuracy was obtained on the ResNet network (86.27%). Using weakly correlated data for transfer training, the highest accuracy was on the VGG network (92.16%). Using strongly correlated data for transfer training, the highest accuracy was also on the VGG network (98.04%). In all network architectures, transfer learning improved the correct recognition rate of convolutional neural network models. Experiments show that transfer learning combined with deep learning improves the accuracy and generalization of the convolutional neural network in the case of small sample sizes.

Commercial grade items dedication provides an in-depth analysis of key characteristics of commercial grade items. Technical acceptance of commercial grade items dedication is targeted. Commercial grade items dedication can improve the quality control level of nuclear power plant equipment and effectively compensate for the deficiencies in the process control and quality uncertainties. This article sorts out the differences between ISO9001 and HAF003 and RCC-E requirements, and analyzes the document system, work process, key characteristics, acceptance methods and evaluation process of the commercial grade items dedication of the emergency diesel generator set liquid level transmitter.

ITO thin films were deposited on sapphire substrates under different deposition parameters via ion-assistant electron beam evaporation method. Microstructure characteristics such as crystalline structure and surface morphology of as-deposited ITO thin films were studied by using X-ray diffraction spectroscopy, transmission electron microscopy and field emission scanning electron microscopy, as well as the index of sheet resistance, carrier concentration, carrier mobility and transmission in visible spectrum were tested by means of Hall effect tester and UV-VIS-NIR spectrophotometer, respectively. The influence and impact mechanism of microstructure characteristic on electrical properties of as-deposited ITO thin films were investigated and analyzed in detail.

CO2 capture,utilization and storage (CCUS) is now recognized as an important technology in the global scope of CO2 emission reduction, pipeline transportation is the main center to connect the capture point and the use storage point, the first issue to CO2 pipeline transportation is to solve CO2 source quality research. Yanchang Oilfield has the advantages of CCUS, its coal chemical capture of CO2 contains different impurities. In the CO2 pipeline transportation, the impurity content in CO2 is based on its end use and the actual situation of pipeline. The impurities will affect the efficiency of CO2-EOR, the choice of CO2 state equation, the changes of CO2 phase diagram and the capacity of pipeline transportation.

The pyrolysis and combustion characteristics of a waste oil absorbing activated carbon were investigated using a thermogravimetric analyzer under heating rate of 10°C/min from 25°C to 1000°C. The activated carbon sample was used to adsorb waste oil. The results obtained, indicates that DTG curves of the pyrolysis process of the sample has three peaks at 106°C, 190°C and 249°C. The four peaks are observed in the DTG curves of the incineration process. The first peak at 110°C is caused by water emission. The second peak corresponds to the temperature of 190°C that is consistent with the second peak temperature of the pyrolysis process of the sample. The third peak at 240°C which is 9°C lower than the third peak temperature of the pyrolysis process. The second and third peaks maybe caused by the emission of the waste oil absorbed in the activated carbon. The fourth peak temperature is 516°C and the weight loss within the range of 400°C ~ 560°C is more obvious. The weight loss is caused by the residue char combustion.

As pointed out in several previous works, new drying technologies must be developed to ensure lignite remained competitive. In order to design and test them, it was needed to have a better understanding of the characters of water in lignite. Using differential scanning calorimetry (DSC), three types of the water storing in the lignite were determined from congelation character. The contents of the free water and bound water were experimentally measured from their heats of congelation, respectively. The results shows that the congelation temperature and the freezing heat per weight unit of the bound water vary in different types of lignite. It is deduced that the bound water in lignite can reflect the character of lignite. Besides, the total water content of free water and bound water is less than that measured by fully drying at 105°C. Therefore, it is deduced that there is a kind of water not frozen in the lignite, possibly because its molecular cluster is too small.

The electronic and geometric structures of Sr/Si surface were investigated by Scanning Tunneling Microscopy. One-dimensional(1D) atomic concerted motion phenomenon was observed on this surface. Three reasons contribute to this phenomenon: First, low metal coverage of 1/6 monolayer with low energy occupation sites; second, weak interaction between Sr and Si substrate; third, surface vacancy formed in the high temperature annealing process and thermal fluctuation energy at room temperature. This findings lead to the conclusions that (3×2) reconstruction of Sr/Si system behave typical one-dimensional diffusion property at room temperature.

Lightning has become a big threat to the safe operation of the main transmission line. Reasonable and accurate calculation of shielding failure rate plays important role in transmission line and tower design. This paper proposes a hybrid approach to calculate the shielding failure-caused trip-out rate, based on the typical electro-geometric model and the regulation method. The case study prove the validity and correctness of this approach, by comparing with the actual operation shielding failure rate.

Cartilage is a hydrated connective tissue that withstands and distributes mechanical forces within joints. Chondrocytes utilize mechanical signals to maintain cartilaginous tissue homeostasis. They regulate their metabolic activity through complex biological and biophysical interactions with the extracellular matrix (ECM). Some mechanotransduction mechanisms are known, while many others no doubt remain to be discovered. Various aspects of chondrocyte mechanobiology have been applied to tissue engineering, with the creation of replacement tissue in vitro from bioresorbable or non-bioresorbable scaffolds and harvested cells. The tissues are maintained in a near-physiologic mechanical and biochemical environment. This paper is an overview of both chondrocyte mechanobiology and cartilage tissue engineering