bluuebunny/crossref_metadata_2025 huggingface dataset:
Multi-objective optimal dispatching of microgrid based on improved genetic algorithm
Authors: Chen H D , An Y , Meng X C
Published: July 2019

Aiming at the optimization problem of micro-grid energy dispatch, the environmental benefit, system operation and maintenance cost, start-stop cost and main grid electricity price are proposed as the objective function, and the influence of the actual operation constraints of micro-grid system and the distributed non-scheduled new energy are taken into account at the same time. The multi-objective optimal dispatching model of microgrid is constructed, and the model is solved based on improved genetic algorithm. The numerical simulation results show that compared with the traditional single-target scheduling method of microgrid, the optimal scheduling method of this paper is beneficial to the micro-grid in the process of scheduling decision-making to achieve the overall coordination of economic, environmental and social benefits of microgrid.
Study on Hydrological Characteristics of Large Permeable Parking lot in Sponge City
Authors: Ziang Zhu , Jianguang Xie , Sheng Gu , Gao Lei , Liu YanPing
Published: July 2019

Pervious pavement of large parking lot in sponge city is a new structural form, which is conducive to solving the problem of deterioration of urban ecological environment. The hydrological characteristics of large permeable parking lot are studied. The results show that the effect of large permeable parking lot on flow delay is obvious. No runoff occurs in the structure of large permeable parking lot when the maximum rainfall intensity reaches 0.968 mm/min. When the recurrence period increases from one year to 100 years, the percentage of total runoff reduction are 100%, 66%, 56%, 48%, 44%, and the peak flow reduction rate are 100%, 58%, 50%, 46%, 41%, respectively. With the extension of rainfall recurrence period, the total amount of runoff reduction in large permeable parking lots increased, and the reduction rate showed a downward trend. The research results can provide reference for the construction of large permeable parking lot in sponge city.
Feasibility analysis of residential building adopts household fireplace instead of centralized heating in Dezhou
Authors: Zhimei Wen , Fenghe Zhang
Published: July 2019

Analyzing the heating scheme of residential buildings to use gas as fuel in winter, this paper chooses municipal thermal central heating and household gas-fired boilers to compare energy utilization, initial investment and operating costs. The results show that the advantages of household type gas wall-hanging furnace for independent heating are significantly higher than that of municipal heating. The research can provide reference for the heating of residential buildings in Dezhou in the future.
Research on the security of communication addressing and reporting system of civil aircraft
Authors: Lu Xu
Published: July 2019

ACARS is a digital data link system that transmits short messages by radio or satellite between aircraft and ground stations. ACARS control centre is connected with each ACARS ground station and each airline information centre through the ground communication network. Exchange data and information with airlines in both directions through code addressing. However, because ACARS messages use plaintext transmission, anyone can monitor and decode ACARS messages with a low-cost receiver and obtain details such as aircraft type, location, planned route, passenger status and aircraft operation state, etc., thus posing a major threat to flight safety. The following security problems exist in the current ACARS system.
Study on two - dimensional linear harmonic oscillator characteristics based on MATLAB software
Authors: Fu Xijin
Published: July 2019

Based on the theory of quantum mechanics, this paper systematically analyzes the basic characteristics of n-dimensional linear harmonic oscillator in quantum mechanics, focuses on the eigenfunction and probability density of one-dimensional harmonic oscillator, and simulates the eigenfunction and probability density of some energy levels with MATLAB software. Finally, MATLAB software was used to compare the probability distribution of linear harmonic oscillator in classical mechanics and quantum mechanics. The results indicate that the number of points of intersection between a wave function and a φ=0 line is n; The probability distribution satisfies the normalization condition; Taking different values of n, the probability distribution function of harmonic oscillator in quantum mechanics has n different nodes, and the amplitude of harmonic oscillator in classical mechanics also changes accordingly. φ0
by the ground state probability distribution of quantum mechanics and classical mechanics distribution probability of the simulation image can be seen that the shape of the two distribution curve is the opposite, but when n is large, the probability density of quantum mechanics |ϕn
(ξ)|2 local average and classical probability distribution P(ξ), that is, classical mechanics and quantum mechanics ZhongZhen gradually increase the probability distribution of similarity. These results are reflected in the image, and the characteristics shown in the image are consistent with the theoretical results.
Effect of Diatomite on Thermal Insulation Properties of Straw Fiber Cement-based Composites
Authors: Xiao Li-guang , Liu Xi-xu
Published: July 2019

This paper mainly studies the effect of Diatomite Content on the thermal insulation performance of straw fiber cement-based composites. The test shows that 30% sulphoaluminate cement is replaced by ordinary Portland cement. XRD test showed that the diffraction peaks of Ca (OH)2 and Ettringite were stronger than those of ordinary Portland cement, and the crystallization effect was better. The compressive strength and flexural strength increased by 7.6% and 20% respectively. With the increase of diatomite content, the dry density and thermal conductivity of the composite decreased. When diatomite content was 25% of the total cementitious material, the dry density of the composite was 1068.37 kg/m3, and the thermal conductivity could reach 0.1163 W/(m.K). The thermal insulation performance of the composite could be significantly improved by adding diatomite.
Evaluation of Non-uniformity of Specimen During Hollow Torsional Test
Authors: Xu Binbin
Published: July 2019

Using the proposed evaluating method, the variation of non-uniformity of the mean effective stress and the stress ratio and their distribution along the radius direction are discussed and explained in detail. It is found that there are several peak for the non-uniformity of mean effective stress but only one peak for the stress ratio. As the apparent shear strain increases, the distribution of mean effective stress and stress ratio along the radius also varies and the outer is always faster than the inner.
Flotation Separation of Cadmium by NaCl-KI- Butyl Rhodamine B System
Authors: Tu Changqing , Wen Xinrong
Published: July 2019

The flotation separation behaviors and conditions of Cadmium(II) by NaCl-KI-Bu-RhB system are studied. The results show that when the amount of NaCl is 1.0 g, the amount of 0.001mol/L Bu-RhB solution is 1.50 mL and 0.1 mol/L KI solution is 0.75 mL, Cadmium(II) is floated quantitatively at pH 2.0. While Mn2+, Ni2+, Zn2+ and Co2+ could not be floated. The method of flotation separation of trace Cadmium(II) is established. The flotation separation of Cadmium(II) in the sample of synthetic water is performed, and the recoveries are 103.0%∼109.2%.
Sorption Properties of Ion-imprinted Seaweed-Chitosan Composite Adsorbents for Nickel Ions
Authors: Lu Shuai , Yang Fan , Tian Chunyu , Shi Pu , Liu Xinyuan , Bao Zhenbo , Nie Jiamin
Published: July 2019

A granulated biosorbent-Ni-SC (Ni2+ ions imprinted seaweed-chitosan) was made by seaweed powder encapsulated with cross-linked chitosan and ion-imprint technology in this study. Ni-SC and granulated SC biosorbent (without ion-imprint technology) were investigated for nickel ions removal. The maximum nickel adsorption capacity of Ni-SC and SC were both achieved at pH 7.0 and the capacity of Ni-SC was higher than that of SC. The diffusion-controlled model and pseudo-second-order model were used to fit the adsorption kinetics data. The adsorption capacity of Ni-SC was higher than that of SC during the whole kinetics process. Also the adsorption isotherm study showed that the maximum adsorption capacity of Ni-SC (0.99 mmol·g−1) was higher than that of SC (0.41 mmol·g−1). The Thomas model can well describe the dynamic adsorption observations and the maximum column adsorption capacity qmax was 0.24 mmol·g−1.
Research on the solution of upward movement of agricultural products
Authors: Zhang Yuchen , Xu Wensheng , Wang Yanmei
Published: July 2019

Upward movement of agricultural products is an operation mode in which rural e-commerce is used as a medium to open the sales channels of local characteristic agricultural products so that the characteristic agricultural products can reach the dining tables of the common people from the fields. With the advent of the mobile Internet and big data era, the upward movement of agricultural products must be based on this trend and keep up with the development trend. Firstly, the article analyzes the current situation and existing problems of agricultural products. A transportation solution for agricultural products has been established. Finally, the implementation measures for the upward movement of agricultural products are put forward.
Experimental study on desulfurization at low temperature with plasma modified calcium-based adsorbent
Authors: Liu Yuan
Published: July 2019

Activated carbon and quicklime were used to prepare complex calcium based adsorbent for flue gas desulphurization. The desulfurization properties of adsorbent were analyzed on fixed bed. The results showed that the desulfurization effect of the composite adsorbent was best when the ratio of activated carbon to calcium was 1:2, the water heating time was 24 hours and heating temperature was 90 °C. At the same time, low temperature plasma technology is used to ionize the composite adsorbent, increase the number of surface chemical functional groups of the adsorbent, and then improve its desulfurization efficiency. The effect of modification time and power on desulfurization efficiency was studied. The results show that low temperature plasma ionization modification can obviously improve the desulfurization performance of composite adsorbent.
Applicaiton of NiTi memory alloy dish gasket in power grid
Authors: Li Wenbo , Liu Lanlan , Yang Yinfei , Xie Yi , Chen Junjun , Sun Lipeng , Long Yi
Published: July 2019

Dish-shaped gasket (DSG) was prepared to use NiTi shape memory alloy (SMA) for the current study. The recovery force of the NiTi SMA based DSG increases with the rise of temperature. The DSG can supply a recovery force of 5.89 kN at 95 °C. The NiTi SMA based DSG can effectively decrease the loop resistance of the clamps to less than 30μΩ under the heating of the clamps, and it also can continuously suppress the heating of the clamp until the height of the nut loosening exceeds the original height of the DSG.
Design of front-end push-pull sine wave inverter
Authors: Zhou Shijin , He Jin , Yang Fan , Cao Lucheng , Li Ke
Published: July 2019

This paper designs a sine wave inverter that converts 12V DC into 220V/50Hz AC. In the DC/DC converter circuit, the push-pull circuit is used for boosting. The pulse width modulator SG3525 control chip is selected. The MOS tube provides the drive signal modulation wave, first boosts the 12V DC voltage to 400V; then designs the full-bridge DC/AC converter circuit, selects the control circuit based on the SPWM dedicated chip EG8010 and the drive circuit based on the IR2110S driver chip. Finally, according to the hardware circuit and parameter design, the simulation of the design scheme is carried out, and the feasibility of the design scheme of the sine wave inverter is verified.
Safety Performance Assessment Strategies of P91 Steel Based on Leeb Hardness
Authors: Li Dengke , Hu Sheng , Liu Xing , Xie Yi , Feng Chao
Published: July 2019

A study on the low hardness problem of P91 steel was conducted in this paper by a variety of analytical testing methods, including hardness testing, chemical composition analysis, metallographic examination and mechanical properties testing. A significant discrepancy was revealed between the hardness HBHLD, which is converted from Leeb hardness, and Brinell hardness HB. The intrinsic correlation between hardness and metallographic microstructure and mechanical properties was then established. At last, we have concluded the safety performance assessment strategies of P91 steel based on Leeb hardness testing results.
Effect of Welding Sequence on Welding Deformation and Re-sidual Stress of Ear Plate Structure
Authors: Zhang Guizhi , Zhang Liping , Huang Song , Cheng Hao
Published: July 2019

In this study, a three-dimensional finite element model of the welding process of the ear plate structure was established based on the thermal elastic-plastic method. The DOE method was used to design the welding sequence optimization scheme, and the effect of welding sequence on welding deformation and residual stress was studied. The results show that the variation of welding sequence has little effect on the residual stress of the ear plate structure, but has great influence on the post-weld deformation. Considering the field welding conditions, the reasonable welding sequence was determined finally, and it could meet the assembly design requirements of ear plate structure.
Preparation and Properties of Graphene Anticorrosive Coatings for Transmission Towers
Authors: Yang Liu , Xin Li , Yu He Zhen , Ju Zhao Yue , Jing Du , Hui Wang Jian , Li Zheng Yong
Published: July 2019

The transmission tower is one of the largest equipment facilities in the transmission and distribution line network. It is mainly used to support the connection of overhead conductors to ensure the safe and stable transmission of power transmission lines. Due to the vast territory of China and the wide distribution of transmission towers, the operating environment faced by transmission towers is also extremely complex. In addition to the pulling force given by the transmission line, rain, snow, dust, salt spray, acid rain and other substances cause erosion and corrosion on the transmission tower. The use of anti-corrosion coatings is an effective way to avoid erosion and corrosion of transmission tower. Therefore, it is very important to prepare an anti-corrosion coating suitable for transmission towers for the safe operation of transmission towers. Graphene is a new type of functional nano-material that attracts attention. Its special layered structure can effectively shield the material, reduce the internal stress of the coating, and improve the adhesion, mechanical properties, anti-corrosion effect and other properties of the coating.
Performance and Damage Evaluations of Fracturing Fluid in Tight Sandstone Oil Reservoirs
Authors: Liu X F
Published: July 2019

Fracturing fluid from M oilfield, Ordos’s basin, China was investigated. The shear viscosity, emulsification and demulsification performance, residual content in gel breaking fluid, compatibility among foreign fluid and formation water, and permeability damage were separately analyzed. Results show that the fracturing fluid system has better shear properties and sand carrying capacity at high temperature. The emulsification rate reached more than 60%, while the demulsification rate was less than 25%. The compatibility among working fluid and the formation water was relatively poor and precipitation was easily to generate. The residue content in broken gel was relatively low but the residue particles were more likely to enter micro fractures; permeability damage was moderately weak in fractured samples.
Research on Multi-Dimensional Closed-Loop Management and Control Mode of Schedule Investment for Power Grid Infrastructure Projects
Authors: Zhang Jian , Jin Xianing , Song Yi , Yang Weihong , Zhang Mingli , Gao Jing , Yang Bo , Li Zhanjun , Wang Yihe
Published: July 2019

With the deepening of external power transmission and distribution price reform and other policies, the work program of “optimize operation and management strategy, promote quality and efficiency development” within the power grid company has put forward clear requirements for the coordination of multiple majors, such as planning, construction, transportation and inspection, and materials. Starting from the actual management demand of investment chain, we build collaborative control standards of investment, standard control model, the innovative power grid construction project investment in multi-dimensional closed-loop control mode, and apply it to the investment management process, in order to extend investment value management to business terminals, constantly improve the management of scientific, validity and accuracy, and assist the company in multi-dimensional lean management and control.
Research on Investment Demand Forecast of Power Grid Based on Grey System Theory
Authors: Li Hui , Wang Yongli , Peng Dong , Wang Zhidong , Ma Yuze , Zhang Fuli , Zhao Lang , Xue Yawei
Published: July 2019

The forecast of power grid investment demand is of great significance for reasonably arranging the investment of power grid construction funds and reducing the cost of funds. In this paper, a forecasting model of power grid investment demand based on grey system theory is proposed. Firstly, the correlation coefficient method is used to analyze the correlation between the investment demand of power grid and its influencing factors, and the key factors affecting the investment demand of power grid are selected. Then the grey relational grade analysis theory is used to construct the investment demand forecasting model of power grid. The validity and rationality of the model are verified by an example of power grid investment prediction in a certain area. The model is of great theoretical and practical significance for the coordination of power grid investment and the scientific planning of power grid investment scale.
Suggestions on Perfecting the Equity and Dividend Incentive Policies of State-owned Science and Technology Enterprises
Authors: Shude Shi , Han Wang , Yan Chang
Published: July 2019

The implementation of state-owned technology-based enterprise equity and dividend incentive policies is of great significance to improving the enthusiasm of state-owned enterprises’ scientific and technological personnel, reducing the loss of core employees, accelerating the transformation of scientific and technological achievements, and improving the economic benefits of enterprises. However, in the implementation process of the policy, there are realistic problems and obstacles: the first is the scope of implementation of the policy; the second is the unreasonable setting of policy implementation constraints; the third is the inherent thinking and habits of the enterprise; the fourth is the actual operation has concerns and difficulties. Based on the analysis and research, this paper puts forward some suggestions: the first is to reduce the constraints of policy implementation and further enhance the autonomy of enterprises; the second is to expand the scope of policy implementation and appropriately increase incentives; the third is to enhance policy operability by increasing policy advocacy and communication.
Management of Power Supply System for Civil Aircraft
Authors: Lu Xu
Published: July 2019

A control method based on Kinect for robots is proposed in this paper. For the motion control system of two-wheel robot, the method, which is combined with Kinect and DTW gesture recognition, is referred to the field of robotic control, and it can be applied in human-computer interaction system. A series of experiments indicate that this method can realize the dynamic gesture recognition and it has a good performance of real-time and robustness.
Calibrating measured milling force during long-duration monitoring
Authors: Liang Chou-Fu , Zheng Charles M.
Published: July 2019

Piezoelectric force sensor is used to measure cutting force in most milling process to get important manufacturing information. However, the measured milling force may be not accurate due to the charge leak in piezoelectric sensor during long-duration monitoring, which will cause a zero-drift problem in measuring milling force. Measuring milling force with zero-drift problem, the measured average cutting force should be calibrated in order to get correct force information. In this study, the measured first harmonic force components are used to calibrate average cutting force components based on cutting force model. There are two steps in this method for calibrating average force components. The first step uses the measured first harmonic force components to extract the specific cutting constants from the ratio of the measured first harmonic force components in X and Y directions, and the second step utilizes the identified cutting constants to calibrate the average force components. The limitations of presented method are also discussed in this paper. The validity of the proposed method is confirmed through milling experiments.
Objective of Education Reform and Application Idea of Cooperation between college and enterprise on the Course-Education of Construction steel structure fabrication technology
Authors: Jin Xiaoqun , Yao Jian , Sheng and Li
Published: July 2019

Construction steel structure fabrication technology is one of the featured courses in the field of steel structure, and this course is closely related to applied engineering. To better cultivate application-oriented talents, this course adopts the college-enterprise joint lecture mode, adopting revolutionary approaches such as making course plans, constructing internship bases, compiling and editing textbooks and giving jointed lectures together with steel structure companies to enhance the effectiveness of the instruction and improve students’ creativity. Through 10 years of in-depth college -enterprise cooperation, we have achieved remarkable results and temporary success, and we believe our example will provide an exemplary case for the reform of similar courses as well as a new idea for the cultivation of application-oriented civil engineering talents.
Dynamic testing of prefabricated concrete frame hook-type joints
Authors: Gu Wei , Chang Zhongquan , Zhang Xinxin , Zhang Yannian
Published: July 2019

A new type of prefabricated concrete beam-column hook-type joint with simple structure and convenient installation was proposed. In order to comprehensively evaluate the dynamic behaviour of a newly hook-type joint, dynamic tests were carried out on five full size model specimens with different strength grade of concrete and steel bar. The seismic behavior parameters such as failure pattern, bearing capacity, and hysteresis loop and ductility coefficient of each specimen were analyzed, and the strain distribution of post-pouring band were studied. Experiment results show that the destruction process of prefabricated concrete hook-type joints has the initial crack, through crack, beam yield, limit, and destroyed stages. The hysteretic loop is plump and has good plastic deformation ability, and the ductility coefficients are above 3.5, which indicate that the hook-type joints have good ductility. The analysis results shows that the steel bar strains in the post-pouring band continue to increase steadily after the joints yield, which means it has good working performance. Therefore, the hook-type joint of the prefabricated concrete frame have good seismic performance and reliability.
Game model of three-party shared risk allocation for PPP projects ---based on the perspective of incomplete information
Authors: Zhang Peipei , Zhan Kuo , Zhou Ying
Published: July 2019

PPP projects involve multi-stakeholders. Rational allocation of risk among project participants is the basis and key to the smooth operation of PPP projects. In the past, most of the studies have only considered the public and private parties, but ignored the bank as the project participant to share the project risk. Therefore, using the bargaining game theory, this paper bulids a bargaining game model in which the three parties (government, enterprise and bank) of PPP project deter each other under incomplete information, and works out the corresponding sub-game refined Nash equilibrium, then obtains the proportion of risk sharing among the three participants. The research results provide a scientific basis for project participants to make decision on risk sharing, which is conducive to improving the willingness of project participants to cooperate, and also play a supplementary role in PPP project risk sharing research.
3D visualization of urban underground pipelines by using SuperMap
Authors: Wen Feng Kai , Wen Lan Gui , Juan Yue Xiao , Yang Pang Li , Yu Tao Yan
Published: July 2019

For the complicated structure and spatial relationship of urban underground pipelines, it’s necessary to employ 3D visualization technology in pipeline management and maintenance. It’s not efficient to use 3D modelling software such as 3DS MAX in building a large range scene, and it’s difficult and cumbersome to develop the functionalities for 3D visualization of urban underground pipelines from scratch by using the programming APIs such as OpenGL and DirectX3D. In this paper, based on the 3D visualization controls and interfaces by SuperMap, an adaptive method is proposed for building 3D models of urban underground pipeline network. At first, the detailed models of the pipe points and pipe segments are designed by 3DS MAX and imported as map symbols into a SuperMap Symbol library. Then the whole pipeline network is loaded and transformed into a 3D scene by using SuperMap interfaces. Moreover, the 3D models of the ground objects such as buildings are cached in OSGB format, and rendered with underground pipelines to support interactive queries and some professional analysis.
The Research and Control Measures of the Influence on the Complicated tie-line and the Bridge under the Shield Tunnel
Authors: Wang Hao , Liu Junyan , Zhang Liangliang
Published: July 2019

The analysis and calculation of the influence of Shield Tunnels Crossing Existing Railways and bridges considering the time-space effect is of great significance to the risk control of shield tunnels. Taking the long-distance bus station-production Road station section of Jinan rail transit line R2 as an example, shield tunnelling method is used to construct the shield tunnels in this section, and the shield tunnels are crossed under the Beibei Bridge of Beijing-Jiaozuo Liaison Line and Beijing-Shanghai Link In order to study the influence of shield tunnelling on railway and bridge piles, three-dimensional finite element numerical analysis method is used to establish a three-dimensional finite element analysis model through MIDAS/GTS. The position relationship of shield tunnels, railways and bridge piles and the shield tunnelling distance are simulated. The stress of railway subgrade and pile foundation caused by shield tunnelling is analyzed. The result of deformation is within the allowable value of deformation control of railway and bridge. Without any reinforcement measures, through monitoring the deformation of subgrade and bridge, timely feedback of monitoring information and timely adjustment of shield tunnelling parameters, shield tunnelling can safely Cross railway and bridge. The development of similar projects will provide relevant reference.
Detection of Total Corrosive Sulfur in Transformer Oil
Authors: Wan Tao , Ye Huisheng , Zhou Ting , Gong Shangkun , Huang Haibo , Qian Hui
Published: July 2019

The quantitative analysis methods of the total corrosive sulfur (TCS) in transformer oils were realized using copper powder corroding technique. In this technique, excess copper powder reacted with insulating oils at 150°C for 12 hours to form corrosion product (CU2S). Then, Cu2S was oxidized to CuSO4
2−, and finally dissolved to sulfate solution. There are three methods to test the amount of TCS. SO4
2− solution tested by ion chromatography (IC) or Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES). Moreover, adopted ICP to test total sulfur (TS) in oils before and after corrosion reaction, and the difference value is the content of TCS. Comparing with these methods, it was found that ICP detection of total sulfur (TS) in oils could achieve excellent linearity. The correlation coefficients is R2≥0.999, and the recovery rate is 98.4%∼103.4%.
Analysis of Reinjection Water to Improve Water-flooding Effect for Low-permeability Sandstone Reservoirs
Authors: Gao Pengpeng , Qu Le , Sun Wei
Published: July 2019

Years of oilfield development practice indicates that the quality of injected water plays an important role in the water-injection process to improve the development effect. The low-permeability reservoirs have low yields and strict requirements on water quality indicators, and it is urgent to study the process of oilfield produced water treatment. The damage source and mechanism of re-injection water was discussed, and the compatibility between the reinjection water and the formation of water was analyzed and evaluated. The treatment process of water reinjection was studied, and the recommended indexes on injection water quality for low-permeability reservoirs for water-flooding development was given in this paper that provides a theoretical basis for the research of oilfield water-flooding development and injection water quality indicators for the future.
Research Status and Prospect of Downhole Acceleration Technology Based on Drill String Vibration
Authors: Zhang Guohui , Chen Rong , zhang Xiwen , Hu Gui
Published: July 2019

Drilling acceleration technology has been a research hotspot in the field of drilling engineering. It is an important research direction in the field of ultra-deep well acceleration to find new energy available underground and develop a matching energy conversion method to improve rock-breaking efficiency. In this paper, the characteristics of downhole available energy are analyzed, and the concept of using vertical vibration energy of drill string to increase the speed of rock breaking assisted by jet pressure of downhole drilling fluid is expounded. This paper summarizes the structure and advantages of the developed downhole drilling string vibration reduction and pressurization device and multi-effect synergistic speed-increasing drilling device, and looks forward to the future development direction of deep-well speed-increasing equipment. The acquisition and rational utilization of downhole energy is an important research dirction for the development of speed-up tools in the future.
The Development and Analysis of Primary Frequency Regulation and AGC Test in Shandong Power Grid
Authors: Yu Qingbin , Xin Gang , Cao Yongji , Li Yuanyuan , Yan Qing
Published: July 2019

Based on the 2018 entire-gird primary frequency regulation and AGC test, the concrete procedures and obtained results of Shandong power grid are analyzed at length. In combination with the published standards and specifications, the new techniques adopted in the test are analyzed. And then, according to the emerging problems during the test, the improvement measures and optimization suggestions are proposed. With the help of analyzed results and proposed advices, the further technical supervision work of source-network coordination can be developed and thermal unit performance can be improved.
Study on Optimum Design of Support Technology for Large Section Belt conveying Roadway
Authors: Baichao Song
Published: July 2019

Aiming at the problems of slow excavation speed, large support workload, large number of assistants, high excavation and support cost in belt conveying roadway in a mine at present, the finite difference software FLAC3D is used to establish the numerical simulation model based on the production geological conditions, Through numerical calculation, reasonable supporting parameters such as bolt diameter, length, spacing between rows, number of anchor wire and spacing between the two are determined to support a belt conveying roadway, that realized the optimization of roadway support, improves the driving speed and guarantees the normal continuity of production.
Technical Inspection of High Strength Bolts in Hydropower Plant: Physical and Chemical Inspection
Authors: Li Wenbo , Liu Lanlan , Wang Jun , Xie Yi , Chen Junjun , Hu Jiarui , Sun Lipeng , Long Yi
Published: July 2019

As an important connection part of metal equipment, bolt is widely used in hydraulic power plant. However, the bolt fracture of hydropower plant occurred occasionally, which seriously affected the stable operation of hydropower plant. Based on the analysis of the fracture bolt, the quality problems of the bolt were found: (1) the material is not qualified, (2) the mechanical properties of the bolts are not qualified. Because the misuse of the material and the wrong execution of the heat treatment, the actual strength of the bolts could not meet the nominal strength, leading to the fracture of the bolts during term of service. The detection of chemical composition and hardness testing can effectively monitor the testing quality of bolts, and prevent unqualified bolts into the installation and operation.
Effects of different economic fruit forests on soil nutrients in Qingxi small watershed
Authors: Wang Qianxin , Sun Bowen , Xiong Mingbiao , Yang Yuanxiang , Hou Jun , Sheng Yuzhang
Published: July 2019

Taking Qingxi small watershed in Hanyuan County of Ya’an City as an example, the effects of four different economic fruit forests on the sloping farmland in the dry-hot valley region on the soil nutrient loss before and after the flood season were studied. The results showed that after the flood season, the soil Organic matter(OM) content of the four economic fruit forests increased, which was characterized by large cherry forest > peach forest > pear forest > pepper forest, but no crop cultivated land decreased. Alkali nitrogen(AN) and Available phosphorus(AP) of four economic fruit forests decreased, but the degree of declining was lower than that of cropless cultivated land. The Total nitrogen(TN) content of the soil of the cherry forest and peach forest decreased, but the degree of declining was lower than that of the cropless cultivated land, while the pear and pepper forests increased. The large cherry forest and pepper forest content of Total phosphorus(TP) in the soil was reduced, while the peach and pear forests increased. In terms of OM, large cherries are the best choice for local fruit forest. Pear trees are the best choice for the change of N or P elements. From the comprehensive analysis of soil nutrient changes, pear trees are the best fruit forest in the region.
Study on Mining Technology of Shallow Hole + Deep Hole Shrinkage method with Ductule Grouting in Advance for Roof Reinforcement
Authors: Xia Jianbo , Cheng Yong , Zhao Mingliang , Liu Cong , Wen Yiming
Published: July 2019

In this paper, the mining method of shallow-hole and deep-hole shrinkage with ductule grouting in advance for roof reinforcement is studied, which is used to recover steeply inclined thick orebody with broken roof. The main innovations in mining technology are as follows: the orebody is artificially divided into two layers, the upper layer is mined by shallow hole blasting, the lower layer is mined by parallel deep holes, both layers advance simultaneously from bottom to top, the mining face of the upper layer is 3.6 meters higher than that of the lower layer, thus forming an inverted step working face in which the mining operation and roof protection are carried out, using ductule to reinforce the broken roof by grouting in advance, and arranging bolts systematically to anchor the grouting reinforced layer into deep rock mass. By using the method of orthogonal test design and in-situ experiment, the reasonable construction parameters of ductule grouting are obtained, which have been applied to No. 7 stope of of stage 3840 in Qaza Lead-Zinc Mine in Yunnan Province and achieved good results. By monitoring the displacement of reinforced layer during and after mining, no obvious displacement and collapse are found, which proves the feasibility of this technology. The mining scheme has a good reference value for similar ore deposits with mining technical conditions.
Study on the adsorption and desorption characteristics of Phosphorus in Ryegrass and natural grasses in sloping land of Rainy Area of West China
Authors: Sun Bowen , Wang Qianxin , Zhao Qin , Yang Yuanxiang , Sheng Yuzhang
Published: July 2019

In this study, runoff plot test was carried out in Rainy Area of West China to study the adsorption and analytical characteristics of phosphorus on ryegxass(Lolium perenne L.) and natural grass soil planted on different slopes. The results showed that the content of available phosphorus and total p in ryegrass was higher than that in natural grassland. Langmuir equation can well fit the adsorption of phosphorus on soil, and the maximum adsorption capacity and adsorption coefficient are 434.76mg/kg and 0.57, respectively, which all appear in ryegrass field. The secondary kinetic equation can well fit the adsorption dynamic characteristics of phosphorus. The equilibrium adsorption capacity and adsorption rate are between 44.64∼49.06 mg/kg and 0.0258~0.0466 kg/(mgh), and the maximum value is in ryegrass field. The phosphorus analysis rate of the soil in the study area was 30.93∼34.41%, which showed that the natural grassland was > ryegrass. At the same adsorption amount, the soil phosphorus content was > ryegrass. The results showed that the soil phosphorus fixation effect of ryegrass was good. The rational planting of ryegrass on the slope of yuping district in west China can effectively reduce the pollution of phosphorus from non-point sources.
Analysis of Sediment-retaining Function of “7.26” Storm of Silt Dam in Xiaoli River Basin
Authors: Li Li , Jian Shi Xue , Shan Yang Ji , Li Ma
Published: July 2019

The construction of silt dams on the loess plateau is one of the highlights of water conservancy construction. Because silt dams can effectively prevent soil erosion, silt dams have been built on a large scale in the loess plateau. But what is the function and effect of silt dam in the process of rainstorm? It is a scientific question to be answered urgently. Therefore, we selected six hundred and forty-six silt dams in Xiaoli river basin under “7.26” rainstorm to carry out field survey and measure the silt and sediment situation of silt dams, so as to explore the silt retaining capacity of silt dams in small watersheds and the main factors affecting silt and sediment of silt dams during rainstorm. The results show that the small and medium-sized dams in the Xiaoli river basin have a strong ability to retain sediment in rainstorm, but the large and medium-sized dams play a major role in retaining sediment. The average modulus of retaining sediment in the basin is 12587t/km2.
Research on the characteristics of driver visual behavior in highway extra-long tunnel
Authors: Yang Yunxing , Chen Fang
Published: July 2019

In order to study the driver visual behavior in highway extra-long tunnel section, the paper used Smart Eye Pro5.7 Eye Tracking System to record the driver’s eye movement data, analyzed eye movement index, such as pupil area, X sight angle, Y sight angle, percentage of fixation times, percentage of fixation time and mean fixation time. The results showed that the driver’s pupil area changes rapidly to adapt brightness variation in the entrance and exit of the tunnel. After entering the tunnel, the psychological state of drivers tends to be stable, and there is a tendency of gradual relaxation. Drivers are more focused and look down.
A Summary of Research on Wide-area Distributed Electric Vehicle and Grid Interaction Technology
Authors: Shuanglong Shi , Zhe Yan , Shuaihua Li , Yuheng Xing , Zhengtao Jiang , Huan Xie
Published: July 2019

Electric vehicle charging behavior and grid interaction technology, including the impact assessment of electric vehicles for distribution networks and the planning and operation optimization of electric vehicles connected to the grid.Specifically, the main contents include: researching the agglomeration characteristics of large-scale electric vehicle charging behavior based on statistical data and charging history data, and evaluating the regulatory potential of large-scale electric vehicles; wide-area coordination strategy and station-level and regional-level orderly charging.The interaction mode and architecture, the hierarchical control strategy of large-scale electric vehicle charging behavior and grid interaction.
Global political economy of rare earths: changing positions of major market actors including China, European Union, Japan and United States
Authors: Yan Guangli , Zhongxue LI
Published: July 2019

The availability of rare earth elements became a global concern in 2010 when prices soared after China restricted exports of these metals. What measures can or should states or companies adopt to secure a supply of certain scarce resources where the control of the supply is dominated by only a few nations? This problem is becoming increasingly urgent in the case of rare earths because the global demand for these minerals continues to increase. We investigated the policy measures that countries that are major consumers of rare earths have taken when facing supply disruptions, including China, the European Union, Japan, and the United States. We found that strengthening research and development (R&D) and innovation became the first choice of these countries; in addition, market solutions helped to mitigate the supply risk. The supply disruption caused by China’s restrictions on the export of rare earths in 2010 dissipated a year later; this was caused by recycling and more efficient use of these metals and by initial steps to create new sources or alternative products. This event illustrates that both R&D and innovation are the most important elements related to industrial success rather than administrative interventions.
Removal of tar from coke oven flue gas by emulsion liquid membrane
Authors: Zhang Junjie , Dong Pengxiong , Li Chunying , Li Hongxia
Published: July 2019

The new method for removal tar from coke oven flue gas by emulsion liquid membrane was developed. The W/O emulsion was prepared by using kerosene as organic solvent, L-113B as surfactant, water as internal phase and external phase, respectively. The optimum operating conditions were obtained: The optimum experimental conditions of the ELM process for initial tar concentration of 62.5 mg/L are: absorption time: 40 min; concentration of L-113B: 4% (v/v); emulsification speed: 4000 r/min; volume ratio of emulsion to external water phase: 1:4; gas flow rate: 100 mL/min; stirring speed: 630 r/min; volume ratio of oil phase to internal phase: 1:1. The efficiency of tar removal was about 98 % at optimal operating conditions.
Numerical Study of AlN Growth in MOCVD Heated by Induction
Authors: Lu Ligen , Li Zhiming , Zhao Lili , Guo Runqiu , Feng Lansheng
Published: July 2019

In this paper, the process of growing aluminum nitride(AlN) film in the metal organic chemical vapor deposition(MOCVD) reactor heated by induction was simulated, and several important factors affecting the growth rate were analyzed. The purpose of this study is to explore the relationship between these factors and the growth rate of AlN films, and to provide feasible guidance for the parameter optimization of the growth of AlN film. It was concluded that compared with the pure nitrogen(N2) or hydrogen(H2) as the carrier gas, the growth rate was obviously improved under the conditions of using the mixed carrier gases composed of N2 and H2. In addition, the uniformity of AlN film and the growth rate can be improved with the increase of H2 ratio. It was also found that the growth rate of the film gradually decreased with the increased temperature of the gases introduced into the reactor, but the uniformity increased. Dimer is the main growth precursor of the film. In the parasitic reaction, the trimer has the greatest influence on the film, and the concentration of the polymer is more susceptible to temperature changes.
Design and Research of a New Type of Solar Energy Heat Collection and Heat Exchange System Based on Oil-water Graded Heat Conduction
Authors: Liu Denghua , Zhang Peng , Liu Xuetao
Published: July 2019

A low-carbon society and a low-carbon economy have become a new target for development. In China, construction, industry, and transportation energy consumption take up the major role in the overall energy consumptions. In addition, the present heating technology has a low efficiency with large coal consumption and heavy damage to the environment and damage. Investigation shows that northern China boasts rich solar energy resource, making it suitable for promoting solar heating system, which can bring better economic and social benefits. Research found out a new solar heat collection and exchange system based on oil-water grading heat conduction. It can effectively reduce the conventional energy consumption of the building to achieve low carbonization and even zero energy consumption.
Energy storage configuration for smoothing the output volatility of PV power generation
Authors: Xu Zhicheng , Yuan Bo , Liu Jun , Zheng Kuan , Xu Shenzhi
Published: July 2019

The volatility of photovoltaic (PV) power generation affects its schedulability and friendly grid connection. Energy storage as a highly flexible and controllable regulation resource is regarded as a key technical means to smooth PV power output. This paper proposes a BESS power and capacity determination method based on the definition of maximum PV power volatility and gives an empirical formula for determining the energy storage capacity under different levels of PV output volatility. Furthermore, the determination of BESS under different maximum power volatility constraints and installed capacity of PV plants is also studied. It provides a reference for the actual energy storage planning with different renewable energy penetration levels, which is conducive to the friendly grid connection and dispatch of renewable energy power generation.
Study on the Validity of NOX Uniformity Thermal State Optimization Adjustment Strategy for SCR Denitration Unit of Coal-fired Power Plant
Authors: Yu Honghai , Wang Zhi , Li Chao , He Fengyuan , Qu Litao , Wang Dexin , Qi Xiaohui , Du Jia
Published: July 2019

In order to make the NOx stable discharge standard after the ultra-low emission reform of coal-fired power plants, SCR denitration unit safe and economical operation. Taking a 600MW unit as the research object, the effectiveness of the NOx uniformity thermal state optimization adjustment strategy at the outlet of the denitration unit was studied, and the denitration unit inlet and outlet flow fields and NOx concentration field were tested to analyze the existing problems and formulate an optimization plan. The thermal state optimization adjustment, the NOx uniformity of the denitration unit outlet is significantly improved, the standard deviation of the NOx concentration at each outlet of the load section is reduced to below 15% and the ammonia escape concentration is reduced to below 3ppm. The research shows that the thermal optimization adjustment strategy is reliable and effective for improving the NOx uniformity of the SCR denitration unit, and the unit can operate safely and economically.