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Many factors affect the movement of rockfall. Thus, this study explored the influence of rockfall shape, slope angle, angular velocity, slope hardness, rockfall mass, and slope surface roughness on the stopping position and potential energy loss rate based on an orthogonal experiment. To study the key factors affecting the movement of rockfall, 2500 sets of orthogonal tests were carried out by using ROCFALL 8.0 (ROCSCIENCE) numerical simulation program. SPSS19.0 software was used to perform importance analysis and correlation analysis on the test results. The analysis results show that rockfall shape has the greatest influence on the stopping distance. There is a significant positive linear correlation between the number of rockfall edges and the stopping distance of rockfall on the asphalt road. The slope angle has the greatest influence on the potential energy loss rate, and there is a significant negative linear correlation between the slope angle and the potential energy loss rate. In the case of a low angle slope, the stopping position of rockfall is more concentrated. Therefore, in the process of mountain engineering construction, more attention should be paid to the influence of rockfall shape and slope angle on rockfall hazard protection.

In the present research, the friction and wear behaviour of a hard coating were studied by using ball-on-disc tests to simulate the wear process of the coated tools for sheet metal forming process. The evolution of the friction coefficient followed a typical dual-plateau pattern, i.e. at the initial stage of sliding, the friction coefficient was relatively low, followed by a sharp increase due to the breakdown of the coatings after a certain number of cyclic dynamic loadings. This phenomenon was caused by the interactive response between the friction and wear from a coating tribo-system, which has not been addressed so far by metal forming researchers, and constant friction coefficient values are normally used in the FE simulations to represent the complex tribological nature at the contact interfaces. Meanwhile, most of the current FE simulations are single cycle, whereas most sheet metal forming operations are conducted as multi-cycle. Therefore, a novel friction/wear interactive friction model was developed to, simultaneously, characterise the evolutions of friction coefficient and the remaining thickness of the coating layer, to enable the wear life of coated tooling to be predicted. The friction model was then implemented into the FE simulation of a sheet metal forming process for feasibility study.

In the period of the May Fourth New Culture Movement, under the background of the Europeanization of Chinese with Western learning in the East, a large number of loanwords were absorbed into Chinese in this period due to the extensive language contact. The use of loanwords in Lu Xun's representative vernacular novel Call to Arms embodies Lu Xun's vocabulary concept of constructing modern vernacular. This paper focuses on the study of English loanwords in Call to Arms, and classifies them into four categories: pure transliteration, transliteration and free translation, letter words and Japanese borrowing form words. These words mainly involve the fields of science, technology, politics, humanities and society, at the same time, new affixes and word formation have appeared in modern Chinese. After being introduced and transformed into the Chinese language, they have been continuously integrated into the specific meanings in the Chinese cultural background during the development process, and gradually localized, forming a unique Chinese vocabulary form.

Soil is a crucial component of the ecosystem and a vital resource for its healthy development. Soil pollution is caused by physiological toxic substances or excess plant nutrients, leading to a deterioration of soil properties and physiological dysfunction in plants. Soil pollution takes various forms, such as chemical, physical, and biological. Based on the primary biological entities involved in the remediation of polluted soil, there are three types of remediation methods: microbial, phytoremediation, and animal-mediated remediation. Among these, microbial and phytoremediation are the most widely used. The remediation of contaminated soil is a complex process involving many factors. The use of a single remediation technique is inevitably constrained and can affect the effectiveness of the remediation. Therefore, the remediation of polluted soil must take into account multiple factors and use a combination of several remediation techniques to develop a comprehensive remediation technique that adapts to the site's soil pollution conditions and conditions, combining the advantages of multiple methods to achieve the ultimate goal of completely restoring the polluted soil.

Fine structural interpretation is one of the effective methods to find favorable structural traps and targets. Aiming at the fault interpretation of Jurassic Badaowan Fm in Madong area of Xiayan fault zone is not fine and structural characteristics are not implemented, the structural characteristics of Jurassic Badaowan Fm are implemented and favorable traps are found through the study of seismic, well logging and geological comprehensive methods. The results show that the structure of Jurassic Badaowan Fm in Madong area is high in the north and low in the south. The first member of Badaowan Fm is a delta front subaqueous distributary channel deposit, which is a hydrocarbon enrichment zone. Oil and gas are adjusted along the relay of deep and shallow faults, and the great fault zone and the inherited uplifting zone are favorable accumulation areas of Jurassic Badaowan Fm in Madong area. In this paper, the relationship between deep and shallow fault system and hydrocarbon distribution of Badaowan Fm in Madong area is systematically reviewed for the first time. Combined with the palaeohigh distribution, three favorable hydrocarbon accumulation zones are identified, which provides favorable targets for exploring the hydrocarbon accumulation potential of Badaowan Fm.

In order to avoid the problem of too many AC energy consumption cycles and time-consuming for the standard electric vehicle driving range test, the DC energy consumption test can be used to obtain the energy consumption of the test cycle at any time period and estimate the driving range. However, the rationality of intercepting part of the circulating DC energy consumption to estimate the whole process still lacks sufficient experimental support. Therefore, in this paper, two different electric vehicle prototypes were selected, and a complete energy consumption test experiment was carried out according to the standard test process. Through the test of DC energy consumption, the difference characteristics of electric vehicle driving braking energy and energy consumption under repeated cycles were analyzed. The fluctuation range provides data support for the use of DC power to evaluate the energy consumption of electric vehicles

With the popularization of electric vehicles, more and more attention has been paid to how to select reasonable test methods to evaluate the driving range of electric vehicles. This paper selects two electric vehicle prototypes with different configurations to test the energy consumption of the shortened test cycle at normal temperature and the standard test cycle at low temperature, and analyzes the constant speed working condition in the shortened method and the CLTC-P working condition at low temperature. The results show that both the 100km/h constant speed working condition and the low temperature working condition will cause a significant increase in the energy consumption of electric vehicles, and the energy consumption difference of repeated cycles under the low temperature test condition will also increase significantly compared with that at room temperature. The relevant results are more A comprehensive understanding and evaluation of the energy consumption characteristics of electric vehicles provides a useful reference.

Based on the survey data of the waters of Jiaozhou Bay in May, August and October 1992, the change of Pb content and its deposition process in the surface and bottom waters of Jiaozhou Bay were studied. According to the definition and model of Dongfang Yang’s content changing degree, the variation of Pb content at surface and bottom and of Pb content transported by main sea current formed a peak line in the southeast waters of Jiaozhou Bay. The Pb content on the surface reached its peak in August. From May to August, Dongfang Yang’s content changing degree was 79.84°. However, from August to October, it was -85.29°. Specifically, in surface water, Dongfang Yang’s content changing degree from May to August was 62.48°. From August to October, Dongfang Yang’s content changing degree was -39.00°. In the bottom water, Dongfang Yang’s content changing degree from May to August was 70.41°. From August to October, Dongfang Yang’s content changing degree was -80.03°. It indicates that the change of Pb content in surface nearshore waters passed through by the main sea current was determined by the change of Pb content transported by the current. The change of Pb content in surface seawater through the change of ocean currents increases or decreases the increase or decrease of Pb content in surface water —The Pb content of surface water increased or decreased with the increase or decrease of Pb content transported by main sea currents. The Pb content temporal variation in the surface and bottom of the southeastern waters of Jiaozhou Bay from May to October reveals the Pb content settling law: With the increase of Pb content in surface water, the Pb content in bottom water rose faster than that in surface water. When the Pb content in surface water decreased, the Pb content in bottom water decreased much faster than that in surface water. Therefore, the change mechanism of surface and bottom water caused by source transport is proposed with the corresponding model block diagram and changing degree model of Pb content transported by ocean currents.

Based on thermo-mechanical coupling and elastoplastic theory, a finite element (FE) numerical simulation was adopted to study the stability of slopes in cold regions under freeze-thaw cycles. And the prediction of slope landslide was also studied through the calculation of strength reduction coefficients combination. The result shows that the development of the slope vertical displacement under freeze-thaw cycles can be divided into two stages: rapid stage and stable stage. After combining the two reduction coefficients of cohesion and internal friction of the soil, the maximum vertical displacement on the top of the slope in this region can be calculated as a reference for predicting the slope landslides. Meanwhile, the corresponding safety factor of the slope in the cold region can be obtained according to the reduction coefficients. .

Hydrogen leakage and emission will bring adverse effects to the environment and human health. When it enters a certain concentration range, it will bring the potential explosion. Hydrogen emissions from fuel cell vehicles can be divided into two sources: normal operation of the system and leakage under abnormal circumstances. This paper mainly uses the flowmeter method to measure the hydrogen emission from fuel cell electric vehicle（FCEV）. The different emission characteristics of different types of FCEV under idle and steady cycle conditions were analyzed. The hydrogen emission levels of different types of FCEV under idle and cycle conditions were verified by analyzing and processing the experimental data through a certain amount of hydrogen emission tests of FCEV.

The integration and optimization of nature reserves is an important part of the new round of land and space planning, and it is also an important part of building a system of nature reserves with national parks as the main body. This article takes Gannan Tibetan Autonomous Prefecture, which has many nature reserves and relatively complex conditions as an example, to summarize and study the technical and operational issues involved in the integration and optimization of 30 different types of nature reserves, natural parks and scenic spots in the region. We propose an integration and optimization plan that fits the region, focusing on the treatment of the overlapping and distributed residential land, basic farmland, and major construction projects of each protected area, and provide reasonable suggestions for the integration and optimization of the construction of natural reserves with Chinese characteristics.

The tracking of a given voltage in the traditional double closed-loop proportional integral control in the current power grid simulator has problems such as static difference, delay and oscillation. It is proposed that the voltage outer loop and current inner loop of the inverter side of the power grid simulator adopt proportional integral and quasi-proportional resonance control respectively, and the topology of the inverter adopts a cascaded modular design to establish a single-phase inverter model. Compared with the traditional double closed-loop proportional-integral control, it is verified that the proportional-integral-quasi-proportional resonant controller can effectively improve the system’s ability to track the command voltage and the stability of the output voltage.

In order to ensure the balance of trunk transportation resources, logistics enterprises generally require transport vehicles to return to the initial distribution after completing the transportation task, so as to facilitate the next phase of transportation operations. Most logistics enterprises waste the trunk transportation resources in the whole process of logistics transportation. At this time, we need to choose a comprehensive transportation network optimization method to improve the vehicle loading rate, reduce the transportation cost, and design a new form of trunk transportation network. The article analyzes the operation flow of trunk transportation logistics.

This paper studies the design of clean electric energy alternatives based on electric energy alternative equipment. First, sort out the current research status of energy substitution at home and abroad, and determine the research focus of electric energy substitution; list the electric energy substitution equipment that is suitable for construction, industrial, commercial and other fields, analyze its technical characteristics and specific application scenarios; list each device To analyze the performance of the equipment, establish a multi-factor output model for energy storage and production equipment according to the key influencing factors of the equipment performance coefficient; finally, based the above research, consider the substitutability of each equipment With complementary characteristics, the design is suitable for high-clean energy electric energy to replace typical structures.

Wave energy has the advantages of high energy density, renewability, and wide distribution, and has been highly valued by many coastal countries. The wave energy conversion device can convert wave energy into electric energy, which is of great significance for alleviating problems such as energy crisis and greenhouse effect. The traditional wave energy conversion device can only gain the energy along the heave direction, and the kinetic energy of the buoy is not fully utilized. To improve the energy utilization efficiency of the wave energy conversion device, this paper proposed a new type of 3-SPS wave energy conversion device. Based on linear waves and Lagrangian equation, a hydrodynamic model of the device was established. The displacement and velocity of the device float under the action of linear waves were analyzed. The results show that the 3-SPS wave energy conversion device can collect the kinetic energy of the buoy in its heaving, surging and pitching movement at the same time; the kinetic energy of the buoy in the heaving direction is much greater than the kinetic energy in the surging and pitching directions; the buoy can capture kinetic energy in multiple directions of motion, indicating that the 3-SPS wave energy conversion device has a high energy utilization efficiency. This paper provides some useful references for the optimal design of the new wave energy device.

For mines with complex natural terrain conditions, especially for open pit mines with poor slope stability; traditional surveying and mapping techniques are difficult to accurately map engineering quantities and have certain safety hazards. Based on the actual production, this paper systematically studies the key technology of multi-view image matching point cloud in the calculation of mining area engineering quantity, and verifies the feasibility and accuracy of it, and compares it with GPS-RTK, traditional aerial survey and other data acquisition technologies. Comparative analysis shows that multi-view image matching point cloud technology has certain advantages in terms of time, accuracy, cost and security risks. 1, a*

For increasing understanding of fundamental hypersonic phenomena, the flight test program, named MF-1, is to gather fundamental scientific and engineering data on the physics and technologies critical to future operational hypersonic flight with low-cost flight test platform, which is built on the retrofitted rockets. The MF-1 program is a hypersonic flight test program executed by China Aerodynamic Research and Development Center (CARDC). The MF-1 flight flew in December 2015. The flight focuses primarily on integration of instrumentation on the test vehicle, with application to boundary layer transition and shock interaction experiments. The MF-1 payload consists of a blunted 7°half angle cone, a cylinder and 33° flare configuration. The payload was boosted to Mach 5.32 utilizing a solid-rocket booster without control for the whole flight. The flight was fully successful, and measured transition under supersonic and hypersonic conditions. The heat flux data were given by the three-dimensional thermal identification method to discriminate transition zone. The preliminary analysis shows that the real-time flight data obtained by MF-1 are reliable and can be used to validate the transition predicting model and software. The results show that the existing model is able to predict the transition location of cone at a small angle-of-attack for supersonic or hypersonic flow. This paper describes the MF-1 mission and some general conclusions derived from the experiment.

Furniture products are the main sources of indoor air pollution due to the emission of formaldehyde and volatile organic compounds (VOCs). It is great significant to establish a scientific certification and evaluation system to promote furniture manufacturers to reduce the harmful substances release in furniture products and protect human health in China. This paper describes an investigation on release of formaldehyde, soluble heavy metals, benzene, toluene, xylene and other substances from 28 furniture products by dryer method and environmental chamber method. Studies on current development status of certification and evaluation of harmful substance release from furniture products in China were carried out. Case study of certification and evaluation method suitable for furniture production industry was made, and the existing problems and suggestions were provided for improvement of certification and evaluation method system based on the characteristics of furniture industry.

The biodiversity and integrity of river ecosystems are depending on the natural streamflow regime. Therefore, assessing alteration of hydrologic regimes becomes a fundamental step in river ecosystem protection and restoration. In this paper, the Range of Variability Approach (RVA) was used to analyze the alteration hydrologic regimes from 1959 to 2016 in the Tang River, the upstream of Baiyangdian Lake Basin, China. Several results can be drawn: (i) annual streamflow presented a decreasing trend, and an abrupt change was detected in 1979; (ii) the significant changed indicators of hydrologic variation in upstream of Baiyangdian Lake Basin were the monthly streamflow in March, April, August, November, time of 3-day and 90-day maximum streamflow, date of maximum streamflow occurrence, rise rate and number of reversals; and (iii) monthly water should be restored in flood and delivered in non-flood season, and annual extreme streamflow frequency and duration of high and low streamflow also should be regulated to maintain the streamflow regimes in the Tang River Basin, China. The results will help to provide the suitable ecological streamflow and maintain the integrity of river ecosystem in changing environment.

In view of the deployment management problems caused by the service atomization, architecture complexity and large-scale cluster of micro-service architecture system, a PaaS cloud platform automation deployment engine is designed and implemented based on the Docke PaaS platform so as to provide a simple, flexible, efficient, full-stack, full-process deployment solution to the micro service architecture system.

Mengulin sandstone reservoir in Huabei oilfield is low- temperature heavy oil reservoir. Recently, it is at later stage of waterflooding development. The producing degree of water flooding is poor, and it is difficult to keep yield stable. To improve oilfield development effect, according to the characteristics of reservoir geology, microbial enhanced oil recovery to improve oil displacement efficiency is researched. 2 microbial strains suitable for the reservoir conditions were screened indoor. The growth characteristics of strains, compatibility and function mechanism with crude oil were studied. Results show that the screened strains have very strong ability to utilize petroleum hydrocarbon to grow and metabolize, can achieve the purpose of reducing oil viscosity, and can also produce biological molecules with high surface activity to reduce the oil-water interfacial tension. 9 oil wells had been chosen to carry on the pilot test of microbial stimulation, of which 7 wells became effective with better experiment results. The measures effective rate is 77.8%, the increased oil is 1,093.5 tons and the valid is up to 190 days.

The problem of firing control is a critical technology of multi-stage synchronous induction coil launcher (MSSICL). Operation with high launch efficiency of MSSICL mainly depends on each stage driving coil energized when the armature moves on the proper location. In order to solve the problem of firing control for MSSICL, the firing control model of MSSICL is built based on the dynamically simulative model and the firing control criterion. The dynamically simulative model includes the voltage equations of driving circuit and the kinematic equations. The solved method is provided. In addition, the factors that influence the solved precision of the firing control model of MSSICL are analyzed.

This study aims to establish a simple and convenient method suitable for the market to grade the jade colors. Based on the HSL color model and with the assistance of the HSL analysis on green jade images acquired by camera flashlights, this study obtains the following six kinds of jade colors: melon green, emerald green, yellow green, bean green, light bean green, and light green, based on which the law governing the values and the value range can be determined, and the respective HSL value ranges ,together with their threshold values, for the seven green jades can be finally found, thus laying an important foundation for further researches on computer-based quick grading. It is also hoped that this method will be widely applied and promoted in the marketplace and realizes our ultimate goal of setting guidelines to commercial jade prices.

In this paper, the influence of steel rate and substitution rate of iron tailing powder on the bearing capacity of the stub columns is mainly investigated through the test of five concrete stub columns under axial compression loading with square steel tube self-compacting iron tailing, and the test bearing capacity is compared with the bearing capacity calculated by each code. The test results show that the bearing capacity of the test piece increases obviously with the increase of the steel content; the bearing capacity of the test piece is less affected by the substitution rate of iron tailing powder; it is suggested to use code GB50936-2014 to design and calculate the bearing capacity of the stub column under axial compression loading.