bluuebunny/crossref_metadata_2025 huggingface dataset:
High performance organic solar cells based on ZnO: POT2T as an effective cathode interfacial layer
Authors: Du Xiaoyang , Li Xinrui , Chen Quanyi , Lin Hui , Tao Silu
Published: June 2020

Interface engineering in organic solar cells (OSCs) plays an important role in improving electron extraction and suppressing carrier recombination. In this article, the improvement of device was achieved by doping POT2T into ZnO as a new electron transport layer (ETL). For PTB7-Th: PC71BM system, the device fabricated by using ZnO as ETL achieved a PCE of 9.03% with a JSC of 17.33 mA/cm2, a VOC of 0.783V and a FF of 64.17%. After doping 5wt% POT2T in ZnO, the JSC increased to 18.01 mA/cm2 and the FF increased slightly to 69.87%, as a result, the PCE increased to 9.84% with about 10% enhancement. The enhancement is attributed to the improved electron transport and conductivity, optimized ZnO surface morphology after adding POT2T, resulting in higher JSC and FF. Therefore, doping POT2T into ZnO as an ETL is a simple and effective method for obtaining high efficient OSCs.
The embedded discrete fracture model for two-phase flow involving the capillary pressure discontinuities in low-permeability reservoir
Authors: Li Zhanke , Cao Weidong , Liu Zhifeng , Wang Min , Yu Jinbiao , Wang Xiaohong
Published: June 2020

In low permeability reservoirs with conductive fractures, there is large capillary pressure contrast between the matrix and the fracture. It may cause very sharp changes in physical quantities near the matrix-fracture interface, which makes it difficult to calculate the matrix-fracture exchange flux accurately in the traditional embedded fracture model (EDFM). The strong capillary pressure contrast between the matrix and the fracture results in three flow patterns near the matrix-fracture interface and creates difficulty in calculation of the matrix-fracture exchange flux. In this article, a modified embedded discrete fracture model is proposed, where the analytical solutions for the three different patterns are employed to construct the numerical scheme for calculating the matrix-fracture exchange flux. The numerical tests show that the calculated results of the proposed model are in agreement with the reference model in which both the fracture cells and also the matrix cells near the fracture are subdivided sufficiently.
Research and Application of Optimized Integrated Profile Control in Wang 36 Well Area of Wangjiawan Oilfield
Authors: Huang Hongbing , Yang Yong , Yu Haitang , Ouyang Huajing
Published: June 2020

Aiming at the problems of serious heterogeneity of reservoirs in Wang 36 well area of Wangjiawan Oilfield, raPId rise of water cut in the oilfield, poor waterflooding development effect and unsatisfactory effects of conventional single profile control measures. Based on PI decision-making, a comprehensive profile-adjustment decision-making technique based on factors such as heterogeneity of water absorption profile and rising rate of water cut is developed. Field application shows that the overall profile adjustment of the block effectively improves the water flooding effect of Wang 36 block. This method has the characteristics of fastness, practicality and strong operability, and has important guiding significance for comprehensive treatment of similar oilfields.
Application of In-situ Thermal Regeneration Technology in Southern Ring Section of Guangzhou Ring Expressway
Authors: Peng Chenchu , Yang Fang , Feng Liu
Published: June 2020

Based on the South Ring Section of Guangzhou Circum-City Expressway, the characteristics of in-situ thermal regeneration and pavement regeneration technology are analyzed. The pavement performance of the mixture is evaluated by means of immersion residual stability, rutting and freeze-thaw splitting test. The application effect of in-situ thermal regeneration pavement is evaluated by means of seepage test and structural depth test. The results show that the water stability and high temperature stability of recycled asphalt mixture after adding recycling agent are in line with the specifications; the segregation of recycled pavement is large, the seepage is serious, and the seepage and structural depth of overlay recycled pavement meet the requirements; this paper summarizes the application experience and problems in the application process, and provides a reference for similar projects. Basis and improvement direction.
Research on Comprehensive Energy System Analysis Platform of Typical Park
Authors: Nie Wenzhao , Ma Hao , Feng Liwei , Quan Wenlin , Zhang Jing
Published: June 2020

In order to improve the efficiency and accuracy of the comprehensive energy system scheme planning, the research and development of the comprehensive energy system analysis platform in the park was developed. Take the construction of parks (including building parks and industrial parks) as an entry point. Theoretical research is carried out on three aspects of the overall scheme design method of the comprehensive energy system of the park, the influencing factors and analysis methods of the comprehensive energy projects in the park, and the construction of the smart energy integrated management platform. Based on the theoretical research results, the corresponding development of platform tools is proposed, and the platform tools are used to support the planning and design of the integrated energy system of the park and the analysis of investment and operation benefits. The platform research results show that comprehensive energy schemes can be automatically generated and improve accuracy and efficiency. The research results have certain reference and guidance value for the construction and operation of comprehensive energy projects in the subsequent parks.
Study on gas emission prediction of working face based on GM (1, 1) model
Authors: Yuan Benqing
Published: June 2020

At present, the prediction method of gas emission in coal mining face has low precision, based on grey system theory system, grey GM (1, 1) gas emission prediction model is constructed, the real-time, dynamic and non-linear prediction of gas emission is realized, and the application test is carried out in a mine of Huainan mining area. The results show that the average relative error between the predicted value and the measured value is 6.14%, the predicted Index C value is 0.48, P value is 0.90, and the prediction accuracy reaches the second level, which may guide the real-time, dynamic and accurate prediction of gas emission in the coal face.
Research on the Regional Prediction Gas Content Critical Value of 3# Coal Seam in Sangshuping NO.2 Mine
Authors: Jun Liu
Published: June 2020

In order to determine the regional prediction gas content critical value of 3# coal seam in Sangshuping NO.2 Mine, according to the mine’s gas geological conditions, the gas geological units in the investigation area was analyzed and determined. The minimum firmness coefficient f
min, the initial gas release rate ΔP, and the volatility of coal Vdaf
were measured. The outburst empirical formula was used to calculate the minimum gas pressure at which outburst occurred, and then the critical value of gas content was obtained. At the same time, the three-rate analysis method, the correlation analysis of gas content and prominent omen were used to comprehensively determine the critical value of gas content in the normal area of 3# coal seam is 9m3/t in normal area, 8m3/t in geological anomaly area, it provides a scientific basis for regional outburst prevention in the mine.
Galaxy Morphology Classification Based On An Improved Deep Convolutional Neural Network
Authors: Chen Jiawei
Published: June 2020

With each passing day telescopes around and above the Earth capture more and more images of distant galaxies. As better and bigger telescopes continue to collect these images, the datasets begin to explode in size. In order to better understand how the different shapes (or morphologies) of galaxies relate to the physics that create them, such images need to be sorted and classified. Combining with Kaggle public datasets called Galaxy Zoo, this paper devised a deep convolutional neural network for galaxy morphology image classification. The network contains eight convolutional layers, five max_pooling layers, one flatten layer, a fully connected layer contains 150 neurons, as well as the final layer which outputs galaxy category of probability distribution of each image. The experiment results show that our neural network on the validation set of cosine similarity reached to -0.8652 (the closer to -1 means that the closer the predicted output and the expected output), implying that our model for galaxy morphology classification is very effective.
A Novel Method of Music Generation Based on Three Different Recurrent Neural Networks
Authors: Xie Jiatong
Published: June 2020

manuscripts Nowadays, music generation has become an important research field in the study of deep learning. Many different methods such as Generative Adversarial Networks (GAN) and Variational self-encoding (VAE) are already proved to be able to handle such task. In this paper, RNNs, such as LSTM and GRU, will be used to compose the core of the network to predict notes of the melody and generate new music. MIDI will be used as the general music format because of its simple and appropriate data structure that can be coded as a dictionary.
Research on R&D Efficiency Evaluation of Chinese Seed Industry Listed Companies Based on Three-Stage DEA Model
Authors: Yan Linnan
Published: June 2020

In this paper, we measure and analyze the R&D efficiency of 19 seed listed enterprises in China. In order to make the measurement more accurate, We used a three-stage DEA model to exclude the influence of environment variables. After removing the environmental factors, the R&D efficiency and scale efficiency decreased significantly than before, while the pure technical efficiency increased as a whole. This show that the R&D efficiency of seed industry in China is low, mainly affected by the efficiency of scale, and 63% of enterprises are in the state of increasing scale returns. But enterprise scale, the government support, ownership concentration and economic environment for research and development personnel and R&D capital has positive influence on redundancy, which are not conducive to R&D efficiency. Therefore, enterprises should pay attention to the influence of environmental factors, by improving the environmental factors to expand the scale of research and development, and improve the efficiency of its R&D to a certain extent.
Prediction of Heat Transfer Coefficient of PV/T-SAHP Heat Pump System
Authors: Zhou Xingcao , Wu Zezhong , Wang Jigang
Published: June 2020

In order to facilitate performance research and control strategy formulation, Elman neural network is used to predict heat transfer coefficient of heat pump, which is convenient for dynamic modeling of PV/t-sahp system. The accuracy of the prediction model was verified by selecting typical sunny and cloudy days. The experimental results show that the maximum relative errors of the predicted values in sunny and cloudy weather are 5.4% and 7.2% respectively. The mean relative errors were 2.57% and 2.69%, respectively. The results show that the prediction model of Elman neural network proposed in this paper is more accurate and can better simulate the actual operation, which can provide technical support for the follow-up research.
Experimental study on asynchronous injection-production in horizontal well area of low permeability reservoir
Authors: He Yanping
Published: June 2020

Since 2006, a horizontal well area of low-permeability reservoir has experienced the stages of water injection efficiency and comprehensive adjustment after water breakthrough, and the formation pressure has gradually recovered. The relation curve between water cut and recovery percent shows that the development effect of horizontal well zone is obviously better than that of vertical well zone. However, with the increase of the number of the water breakthrough horizontal wells and the adjustment times, the water injection cycle is gradually shortened and the water control cycle is extended. At the same time, the adjustable direction is reduced after water breakthrough, and the contradiction between water supply and water cut is prominent. It is very difficult to stabilize the liquid and control the water in the water cut stage of the horizontal well by conventional single water injection adjustment. Therefore, asynchronous injection-production test is carried out for horizontal wells with multi-stage and multi-direction water breakthrough. It adopts the method of “no production during injection and no injection during production”, plays the role of “dialysis production and effective displacement”, reduces the water cut of oil wells, and excavates the remaining oil between wells. Through numerical simulation and comparison of different injection and production cycle schemes, and through multiple rounds of field tests, the injection and production parameters of asynchronous injection and production tests are continuously optimized as injection 3 and production 5. After the horizontal well is opened, the liquid supply capacity of well is enhanced, the remaining oil of matrix is produced, the water cut is reduced to low water cut, and the oil is increased averagely by 222t of single well, which has achieved good results. It can provide reference basis for water flooding adjustment for the same type of reservoir in the future.
Study Influencing Factors for Energy Consumption of Office Buildings in Severe Cold and Cold Region, China
Authors: Ding Zequn , Zhu Hongqing , Zhou Weiye , Liu Junliang , Bai Zhigang
Published: June 2020

The paper analyzed and studied the factors that affect the energy consumption of office buildings, and some suggests were put forward according to the analysis. Through orthogonal experiment the research selected the exterior wall heat transfer coefficient, exterior window heat transfer coefficient, lighting power density, electricity density, air conditioning system form to analyze and study. Although the ranking factors affecting two models are different, but through the analysis found that the air conditioning system is the greatest impact factor, followed by the lighting equipment, after that is envelope.
Coal Mine Safety Evaluation Based on EWM-Fuzzy comprehensive evaluation Method
Authors: Sun Ling
Published: June 2020

In view of the difficulty in identifying the risk factors in coal mine production system and the subjectivity and complexity of the evaluation methods, a safety evaluation system based on entropy weight method and fuzzy comprehensive evaluation method is proposed. Firstly, the entropy weight method is applied to determine the objective weight of the secondary index of the four mines, which overcomes the disadvantages of strong subjectivity and incomplete information degree. Then the fuzzy comprehensive evaluation method is used to obtain the weight of the first level index, and the safety evaluation value of the whole system is obtained.
Research on Special English Teaching and New Technology Development Based on New Energy Materials
Authors: Zhu Min
Published: June 2020

As a national strategic emerging industry specialty, new energy materials and devices focus on the cultivation of university students’ innovative ability and international competitiveness. Combining professional characteristics and major problems in professional English teaching, explore an open “international conference” teaching model to build a “student-oriented” classroom. Under the guidance of this model, professional English courses, with a focus on both the professional foundation and applied practice, are mainly project-driven learning, which stimulates students’ ability to use professional English in many aspects.
Research on the Influences of Addition of Biodiesel on the Equilibrium Concentrations and Thermodynamic Properties of Combustion Products for Conventional Diesel Fuel
Authors: Han Lei , Shen Haosheng , Zhang Chuan , Yang Baicheng
Published: June 2020

To deal with the increasingly stringent energy crisis and atmospheric pollution problems, biodiesel is regarded as one of the alternative biofuels with great potential for replacing the conventional diesel fuel, thus it is necessary to investigate the influences of addition of biodiesel to conventional diesel fuel on the combustion products. To this end, Jatropha biodiesel is taken as an example and under the assumption that all the combustion products are at chemical equilibrium, a system of nonlinear equations with the equilibrium concentrations of 10 combustion products as the unknown variables is constructed based on the equilibrium constant method and the numerical solutions are obtained by applying Newton-Raphson iterative method. On this basis the influences of biodiesel blending ratio on the equilibrium concentrations of the combustion products and the thermodynamic properties of burned gases mixture is investigated. The simulation results show that the addition of biodiesel does not cause significant influences on the equilibrium concentrations of combustion product, and as the three major greenhouse and poisonous gases, the relative changes of equilibrium concentration for CO2, NO and CO are less than 3.52% but with unclear trends and the influence is more significant at the “fuel rich” condition; on the other hand, the mass-based combustion products rates of CO2, NO and CO for a unity of blended fuel mass increases with blending ratio. For the thermodynamic properties of burned gases mixture, it is observed that both the constant-pressure and -volume specific heat increase slightly. The model presented here can be integrated into the engine dynamic simulation model conveniently, which lays the foundation for investigating the influence of addition of biodiesel on the engine power, economic and emission performance.
A New Characterization of Hamilton Groups with the Smallest Order
Authors: Lu Peng , Lu Bo
Published: June 2020

Let G be a group and τe(G) the set of numbers of elements of G of the same order. In this paper, by τe(G), we get a new characterization of, where Q
8 is the Quaternion group of order 8. We get the theorem following: Theorem. Let G be a non-abelian group, G≅Q
8 if and only if τe(G) = τe(Q
8) = {1,6}.
High-Speed Rail Express Business Forecast Based on Improved Logit Model for Analyzing the Market Prospect of High-Speed Rail Express Business in Hub Cities
Authors: Zhang Xiaomeng , Zhao Qilan , Sun Dawei , Gao Hanlin
Published: June 2020

The mileage of China’s high-speed railway network has grown rapidly, and the total amount of express delivery nationwide has also increased rapidly. Firstly, the GM (1, 1) model is used to predict the express market demand of high-speed railway hub cities in 2025; then the share-sharing model is constructed to calculate the market share of high-speed rail transport using MATLAB software to predict the market demand of high-speed rail express; and finally based on forecast data. Analyze the market prospects and prospects of the high-speed rail express business in hub cities.
The Research on the Architectural Design and Construction Path of Rural Low-Tech Residential Buildings
Authors: Xiao Li
Published: June 2020

At present, such problems as excessive destruction of rural natural environment, excessive consumption of construction resources, excessive construction cost of residential houses, unsustainable development mode, and gradual loss and extinction of traditional construction experience and technology need to be studied and solved urgently. This paper proposes to save the current rural residential buildings with the concept of low-tech, starting from the perspective of space, forms, materials, and technologies, etc., in order to explore the main categories and practical paths suitable for the current rural low-tech residential building design and construction.
Face Liveness Detection Based on Parallel CNN
Authors: Li Xin , Wu Wei , Li Tao , Su Yang , Yang Lilin
Published: June 2020

In this paper, we develop an effective framework based on deep learning for face liveness detection. Liveness detection is a great challenge in computer vision. Over the past decade, the interest of people in safety management has increased, and face recognition technology has gradually expanded into the commercial areas. However, general face recognition systems also present risks in terms of security and are vulnerable to spoofing attacks. Therefore, we propose a practical deep learning framework to improve the accuracy of classification. First, we observe the image and label the areas with outline and facial features. Second, we introduce an attention model, which fuses local features and global features to obtain multi-channel features. Third, we use pyramid structures and multiple convolutional neural networks with different depths to classify them in parallel and combine them with multiple results. We evaluated the performance of this method on the CASIA-SURF data set. Experiments show that the proposed frame-trained human face classifier has better performance than the existing classifier.
Design of Mining Rules and Prediction System for the First Hit Ratio of Artillery
Authors: Zhou Na , Li Yonghao , Guo Qianya , Liu Xinan
Published: June 2020

In order to realize the data-driven cost-effective prediction of the first hit rate of artillery, this paper applies data mining, minHash and other core algorithms and ideas to design a set of artillery first hit ratio correlation with data analysis, storage, analysis, mining and other functions. Rule mining and forecasting system. In this paper, the system architecture, core algorithm and system software of this system are designed. The actual case test of the first hit rate prediction is carried out based on the test data of a certain type of artillery. The analysis of the test results shows that the function of the system is normal and the operation is stable. The average deviation of the predicted test results is 3.08%, which meets the index requirement of the predicted deviation of the first hit ratio of the artillery <5%.
3D Image Segmentation of MRI Prostate Based on a Pytorch Implementation of V-Net
Authors: Liu Yizhou
Published: June 2020

Prostatitis is one of the common diseases in adult males. At present, the MRI prostate volumetric medical image analysis mainly relies on the radiologist’s naked eye localization recognition diagnosis, which is easy to be misdiagnosed due to the fatigue of the doctor. Although the traditional technology uses the Support Vector Machine (SVM) to identify the image, it exists. Manual design features are incomplete and detection accuracy is not high. Recently, with the popularity and breakthrough of convolutional neural networks in the field of computer vision and medical image analysis, the author uses the MRI Prostate MR Image Segmentation 2012 combined with the Vnet method to exploit the depth of open source. Learning framework Pytorch, to achieve 3D image segmentation. The experimental results show that the Dice coefficient of the model on the training set reaches 0.9238 that is, the similarity between the image after cutting and the original image of the original label is 0.9238, and the error value is only 6.42, which is fast and automatic and accurate for intelligent target area painting, thus facilitating the doctor. Diagnosing medical imaging work is conducive to alleviating the imbalance of the proportion of doctors and patients in China.
Dynamic Simulation and Quantitative Risk Assessment of Indoor Heavy Gas Diffusion
Authors: Xin Baoquan , Wan Lu , Dang Wenyi
Published: June 2020

In order to study the dynamic diffusion process and risk of indoor liquid chlorine leakage, large-scale numerical simulation and risk calculation are carried out based on CFD method. Firstly, a full-scale model in 3km range is established based on CFD calculation, and then the chlorine diffusion process in six leakage scenarios is calculated and analyzed based on pool model. The individual risk and social risk of existing conditions and SIS increase are calculated respectively. The results show that the chlorine will diffuse slowly in the room when the small aperture leaks. In case of leakage of middle hole and larger hole diameter, chlorine gas will quickly fill the warehouse and leak to the outside of the warehouse. The influence of leakage pore size on the diffusion distance of chlorine is very obvious. The total diffusion distance of 900ppm chlorine is 24.2m-401.3m, and the diffusion time is 120s-670s respectively. Under the existing conditions, the individual risk and social risk do not meet the risk acceptance criteria. After sis is increased, the risk meets the acceptance criteria.
Study on mechanism of seepage drainage facilities affecting saturated-unsaturated seepage flow field of high tailings dam
Authors: Bi Qian , Wang Yantao , Li Yunhua
Published: June 2020

This article uses a 300m complex high heap tailings dam as an example. Obtain real parameters through laboratory tests and in-situ tests. Establish a two-dimensional finite element numerical model. Consider normal and flood conditions. Consider the three stages of tailings dam height stacking to 135m, 200m and final 300m. two-dimensional finite element seepage field simulation of simultaneously setting dam surface drainage facilities and reservoir bottom drainage facilities, only reservoir bottom drainage facilities, and only dam surface drainage facilities was performed. Through the analysis of results, the bottom seepage drainage facility is not effective when the dam is high or there are complex geological conditions in the dam. The drainage facilities in front of the dam have a better effect on preventing the infiltration line from overflowing the dam surface, but the ability to control the infiltration line is weak.
Study on the Changes of Calcium Carbonate and Organic Carbon in the Soil after the Feldspathic Sandstone and Sand Compounding
Authors: Shi Chendi , Li Juan , Lu Yangjie , Guo Zhen
Published: June 2020

By analyzing the changes of calcium carbonate and free iron oxide in inorganic cement materials in different proportions of the feldspathic sandstone and sand compounding soil under different tillage years (2a and 9a), the calcium carbonate and free soil in the soil were determined in two years. The average content and relationship of iron oxide. The results show that the average content of calcium carbonate is the highest in the mixed soil of feldspathic sandstone and sand in the ratio of 1:2, the ratio is more favorable for the accumulation of calcium carbonate in 0-30cm soil surface inorganic colloid. The difference of organic carbon content in 0-10cm and 10-20cm soil layers was significant, but it was not significant in 20-30cm soil layers. After the mixture of feldspathic sandstone and sand for 9a, the highest content of organic carbon in each soil layer is the mixture of feldspathic sandstone and sand according to 1:1. From the mixture soil which has been cultivated for 9a, the soil layers of 10-20 cm and 20-30 cm, the content of organic carbon tends to be stable in each proportion. The average organic carbon content was 2.00 g/kg in 2a and 3.37 g/kg in 9a, which increased by 68.50% compared with 2a.
Environmental Analysis of New Economy Based on Energy Consumption and International Trade
Authors: Wang Fang
Published: June 2020

The advent of the era of globalization has led to an increasing number of factors affecting the environment. For most countries, the pursuit of large-scale economic growth has led them to a huge international trade market. With the large-scale economic growth, energy demand in most countries has surged, and emissions have also increased significantly. To mitigate environmental pollution, researchers are focusing on the links between energy consumption, economic growth, and environmental pollution. Based on this research background, the thesis uses the validity method of the environmental Kuznets curve theory, which can make an enough contribution to the research on the dynamic relationship between energy consumption, international trade and environmental pollution.
Effect of Surface Texture on the Output Performance of Lateral Sliding-Mode Triboelectric Nanogenerator
Authors: Ji Shengbao , Fu Tie , Hu Yanqiang
Published: June 2020

In the working process of textured sliding-mode Triboelectric Nanogenerator (TENG), triboelectrification and wear occur simultaneously. At present, there is no systematic research on how the size of surface texture affects surface wear and output performance. In this paper, polymer surface with cylindrical texture of different pitches was prepared by photolithography and replication technology. According to the experimental results, the relationship between surface charge density and normal load of textured PI films was determined. Then the wear and electrostatic field of textured sliding-mode TENG were simulated by finite element method. The results show that the surface charge density increases with the contact load. And the open-circuit voltage of the sliding-mode TENG increases with the sliding distance given in this paper. The reason is that the height of textures in the separation zone is higher, which is caused by the shorter in-friction time and less wear, leading to the increased contact load in the next full-contact state. Therefore, more charges caused by the increased contact load tend to induce the higher output voltage. Moreover, textured surface with small pitch has better wear resistance and output characteristics. This research can provide an analytical method and basis for designing of surface texture in sliding-mode TENG.
Practice Teaching Reform of Tourism Management Major in Higher Vocational Education under the Background of New Industry Form
Authors: Chen Lan
Published: June 2020

In recent years, there are many new forms of tourism industry, which have new requirements for employees. At present, the traditional practice teaching does not fully consider the latest development of the industry, which leads to the problem of the disconnection between talent training and actual demand. Based on the analysis of the existing problems of the traditional teaching mode, this paper puts forward the teaching reform measures. The reform is carried out from four aspects, namely, practical teaching objectives, practical teaching contents, teaching methods, teaching means and teaching means, so as to realize the optimization of practical teaching system.
The Intelligent Fault Diagnosis of Diesel Engine Based on the Ensemble Learning
Authors: Shao Mingqi , Wang Jin , Wang Sibo
Published: June 2020

As the source of power, internal combustion engine is widely used. Because the structure of internal combustion engine is complex and the working condition is bad, the possibility of failure is great. The condition monitoring and fault diagnosis of internal combustion engine can discover and eliminate the faults in time, and ensure the safety and reliability of the operation process. With the rapid progress of machine learning technology, fault diagnosis system is gradually moving towards intelligent development. The enesmble learning uses different methods to change the distribution of the original training samples, so as to build multiple different classifiers, and combine these classifiers to get a stronger classifier to make the final decision. In this paper, through the simulation model of 7k98mc diesel engine to simulate the normal and fault conditions of diesel engine, the ensemble learning algorithm is verified. The results show that the ensemble learning algorithm has higher accuracy and better stability than shallow classifiers.
A New Starting Curve Based on Acceleration and Deceleration Theory of Stepping Motor
Authors: Si Yawei , Zhang Lili , Du Yepeng , Wang Haoyu
Published: June 2020

This paper makes a comprehensive analysis of various research methods to improve the sampling accuracy of automatic biochemical analyzer, and confirms that the starting mode of plunger pump is taken as the research object to improve the sampling accuracy. A new type of S-curve is designed based on the S-curve proposed by acceleration and deceleration theory. This new type of curve ensures high precision sample addition by accurately controlling the plunger pump to run the same distance in each step of the stepping motor. In order to confirm the validity of the new S-curve, an experimental platform was established to compare the confirming that the optimized S-curve can obviously improve the stability of the sample addition result.
Moving Load Identification for STS Cranes Based on Hybrid Weighted Regularization Method
Authors: Wang Ligang , Zhang Qing , Sun Yuantao , Qing Xianrong
Published: June 2020

Moving force identification (MFI) is an important inverse problem in the field of structural health monitoring (SHM). However, reasonable signal features of moving forces are rarely considered in the existing MFI methods. Based on the redundant concatenated dictionary and weighted-norm regularization method, a hybrid method is proposed for MFI in this study. The redundant dictionary consists of both trigonometric functions and rectangular functions used for matching the harmonic and impact signal features of unknown moving forces. The weighted-norm regularization method is introduced for formulation of MFI equation, so that the signal features of moving forces can be accurately extracted. In order to assess the accuracy and the feasibility of the proposed method, an experiment based on Ship-to-Shore (STS) crane has been made and the results were discussed.
Numerical Investigation of Fluid Flow and Heat Transfer Characteristics in Helical Tube with Spiral Corrugations
Authors: Wu Zhiwei , Qian Caifu
Published: June 2020

The flow and heat transfer performance of helical tube with spiral corrugation are numerically studied and compared with helical smooth tube. The velocity field, temperature field and synergistic performance at different sections are analyzed. It is found show that the turbulence intensity is enhanced due to the existence of the spiral corrugations, and as a results, the helical tube with spiral corrugations has more efficient heat transfer capability. Compared with the helical smooth tube, the heat transfer performance of helical tube with spiral corrugations is improved by 20-50%, but the pressure drop increases by about 100%.
Numerical simulation and parameter sensitivity analysis for the cooling of rolling rubber-film on cooling-drums
Authors: Ma Wenxin , Yu Hongjie , Liu Yunyun , Qian Caifu
Published: June 2020

Cooling of the rolling rubber-film on cooling-drums is a common practice in the final stage to achieve good quality of the rubber-film. In this paper, the stable heat transfer process of the rubber-film on the cooling-drums was simulated with a simplified fluid rubber-film method. The temperature at the film on each cooling-drum is obtained and compared with experimental measurements. It is found that the simulation results well agree with the measurements, indicating that the method proposed here is valid. In addition, parameter sensitivity on the cooling efficiency of the system were studied to provide the references for engineering applications.
Lighting cooling device based on thermoacoustic effect
Authors: Liu Chunxu , Xu Qiudi
Published: June 2020

The device is designed based on thermoacoustic effect, Through the sound waves to achieve cooling heat dissipation of lighting equipment. The device is arranged on the main heating part of the lighting equipment. External sound waves enter the device through the resonance absorption module, and be integrated into stable acoustic frequency. Based on the thermoacoustic effect, under the effect of sound waves, the stack near one end of the sound waves form the hot end, from one end of the sound waves form the cold end, heat transfer from the hot end of the cold end to constantly. In this process, the lighting equipment heating part of the heat through the device, so as to achieve the purpose of heat dissipation.
Structural design and application analysis of Laval nozzle
Authors: Zhao Lida , Wang Xiang , Xu Jingfeng
Published: June 2020

The purpose of this project is to apply the principle of Laval nozzle to reconstruct the gas stove, improve the combustion efficiency of the gas stove, transform its tail gas products, and reduce the tail gas pollution of the gas stove. In this paper, ANSYS software is used to simulate the Laval nozzle of micro modular liquefied gas micro propulsion system, and the relationship between the size factors of the nozzle and the flow effect of liquefied gas is obtained.
A new home energy-saving gas stove based on multi-jet cutting technology
Authors: Pan Fei , Yang Yan , Zhang Jiankang
Published: June 2020

As one of the indispensable living equipment in Chinese family, the energy conversion efficiency of gas stove has been widely concerned. The purpose of this paper is to apply the principle of multi-jet cutting circle and catalytic combustion technology to transform the gas stove, combine with dune-shaped profile combustion technology, improving the combustion efficiency of the gas stove, reducing the proportion of polluted gas in the exhaust gas and the exhaust gas pollution of the gas stove, so as to achieve the purpose of full premix, low emission, high efficiency combustion of the gas stove.
Improvement of Palletizing Robot’s Clamp Device for Cigarette Products
Authors: Dao Ronggui , Lü Xiaobo , Fei Guangxing , Bao Chongbin , Liu Hongjian , Wang Rui , Cao Yujiang
Published: June 2020

In order to reduce the drop number of cigarette packing cases and downtime during the robot palletizing, and improve palletizing efficiency, the key technology of the robot’s clamp device was improved. The improvement techniques included vacuum suction cups specification optimizing, suction cups horizontal and vertical balancing layout, robot running smoothly, increasing the intake pipe, multi-loop vacuum generator. These techniques were applied to KUKA KR150L 150/3 robot, tested on normal and circular cigarette packing cases such as Yuxi (Hard Harmony)brand produced by Yuxi cigarette factory. The results showed that the improvement of robot palletizing cigarette packing cases is stable, and the average drop number is reduced to 13/month from 123/month before improvement, the number of downtime is reduced to 14 times/month from 125 times/month, the equipment efficiency is improved to 9.6/min. The improvement can provide technical support for the stable operation of the robot palletizing cigarette cases.
Annular Pressure-Volume Interaction Analysis for HPHT Well Based on Multi-scale
Authors: Cao Lihu , Dou Yihua , Wang Kelin , Xue Shuai , Geng Hailong
Published: June 2020

Annulus pressure build-up is a potentially serious issue with high-pressure and high-temperature wells created by annuli which maybe heated up during production. Considering the mass conservation, energy conservation, and heat stability of fluid, the pressure-volume interaction models of multi-scale annulus are established based on PVT and the matrix of micro-annular temperature fields. Results indicate that the pressure-volume interaction moves the balance point of adjacent annulus early, which is a potentially serious issue for well integrity. The relationship between annulus temperature and pressure is linear. Moreover, at the same production, annulus pressure rapidly rises as the temperature increases, and the change rate of temperature increases at a negative exponential function. After the same production time, the relationship among temperature, pressure, and production is a quadratic function.
Coordinated control strategy and protection system of gas-steam combined cycle units
Authors: Liu Junfeng , Ma Xiaolong , Zhang Ruixiang , Gao Yufeng
Published: June 2020

Introduced tianjin Chen tang zhuang coal to natural gas power plant relocation project issue 2 sets of 900 mw level “two tow one” gas-steam combined cycle unit coordinated control system, in view of the different operation way, used the load distribution is different, and introduce the PID algorithm for load distribution is modified, realize the coordination of total load control unit. Under the way of automatic generation control (AGC), with 30 mw/min rate of rise and fall of the load to load disturbance test results show that the unit operation stability, good load capacity and load in the process of adjusting the maximum dynamic load deviation < 6 mw, and the average static load deviation < 4 mw. It also introduced the unit under the different operation modes, gas turbine, waste heat boiler, steam turbine and generator consideration when the tripping happens in the four major equipment failure, the mutual interlocking protection function.
Effect of freezing and thawing on nutrient content of soft rock
Authors: Shi Lei
Published: June 2020

There are few studies on the effects of freeze-thaw on soil nutrients and soil enzymes, which are directly related to soil fertility and soil biological activity. In the past, the research mainly focused on the nitrogen and phosphorus cycle in the growing period of soil, but more and more studies have found that the non growing season in winter and the change of snow cover thickness caused by global warming affect the nitrogen and phosphorus cycle in the soil The influence of environment on the interannual scale can not be ignored. After the freeze-thaw cycle, the total nitrogen content of the soil did not change significantly, compared with that before the freeze-thaw cycle, the available potassium content of the arsenic sandstone increased, but not significantly; the available phosphorus content of the soil in the freeze-thaw cycle decreased.
Survey on Advanced Equipment Fault Diagnosis and Warning Based on Big Data Technique
Authors: Wang Miao , Zhang Zhenming , Li Kai , Si Can , Li Long
Published: June 2020

Faults are main problem of Mechanical equipment. In general, in order to acquire the massive fault information of equipment, a large number of monitoring points need to be established on the equipment, and the number of sensors for the equipment is large, since equipment fault diagnosis enter the era of big data. The successful application of big data technology in track circuit and power equipment system indicates that the big data of equipment contains important information that reveals the evolution and nature of faults. This paper briefly introduces the development of fault diagnosis technology from three aspects: data acquisition, intelligent fault diagnosis approach and remote fault diagnosis. In addition, This paper expounds the development history of fault diagnosis technology, analyzes the challenges of intelligent fault diagnosis in the era of big data, and discusses the development trend of equipment fault diagnosis according to the existing foundation and challenges. Finally, the development trend of equipment fault diagnosis and early warning are pointed based on existing research.
Research Hotspots and Trends of Natural Gas Vehicles: A Visual Analysis Using CiteSpace
Authors: Luo Na , Li Meihui , Dai Jingqi
Published: June 2020

Driven by the optimization of energy structure, environmental pollution control and climate change constraints, natural gas vehicles have high development potential. As a vehicle fuel, natural gas has many advantages, such as abundant reserves, excellent fuel economy and relatively less pollutants, which makes the development of natural gas vehicles more rapid. This paper uses the data analysis system (DAS) composed of Web of Science (WOS) and CiteSpace to sort out the related literature of natural gas vehicles. Through the visual analysis of 529 documents, the research hotspots and trends of natural gas vehicles from 1990 to now are found. Three important clusters are discussed in this paper, among which the future development direction of natural gas vehicles is hybrid gas-electric vehicles, in order to provide reference for the R&D and production activities of natural gas vehicles.
Economic Research and Exploration of Comprehensive Utilization of Energy Based on Advanced System Theory and Technology
Authors: Zhao Zhongling , Wang Xiao
Published: June 2020

Electricity is the prerequisite and important guarantee for the progress and development of human society. It has an important position and role in the national energy strategy. Increasing the share of renewable energy generation in electricity production has a broad and far-reaching impact on the sustainable development of China’s economy and society. Influences. However, due to the intermittent and instability of renewable energy itself, in order to avoid large-scale renewable energy generation from impacting the power grid, the scale of renewable energy generation and grid-connected power are limited to a certain extent. Advanced Adiabatic Compressed Air Energy Storage (AA-CAES) technology uses a heat storage device (TES) to store compressed heat, eliminating the dependence on fossil fuels and achieving “zero emissions.” At present, AA-CAES technology is considered as an energy storage technology with great market development potential. The paper calculates the performance of the system given the input of the air compressor and the output power of the turbine; analyses the parameters such as the storage pressure ratio, convective heat transfer coefficient, and energy release interval time for energy storage density, cycle efficiency and other systems The influence of performance parameters; reveals the temperature and pressure changes of the gas storage chamber with time during a single cycle.
Algorithm Optimization for Cold Start of Collaborative Filtering System
Authors: Wang Shuo , Yang Jing , Zhao Qingchao
Published: June 2020

With the development of network technology, the amount of information on the network has grown and expanded rapidly with an exponential law, and its information organization is heterogeneous, diverse, and distributed. With the vigorous development of Internet information services, the scale of its information resources has also exploded. For ordinary users, the problems of “information trek” and “information overload” on the Internet are becoming increasingly serious. In order to solve the problem of information overload, recommendation system has become an indispensable tool for today’s e-commerce platform, which can help users find valuable information quickly. Collaborative filtering-based recommendation algorithms have been widely applied and studied in recommendation systems. Although the collaborative filtering algorithm has been widely used, there are still problems such as data sparsity, scalability, and cold start, which seriously limit the quality of recommendations. Therefore, collaborative filtering algorithms face many challenges. Especially recommendation systems using collaborative filtering technology. This article discusses the cold start system, the cold start user, and the cold start scenario. Effective use of project content information and user personal information is one of the effective methods to solve the cold start problem, that is, a hybrid recommendation technology combining information filtering and collaborative filtering. This paper proposes a hybrid recommendation technology that can better solve the cold start problem.
Empirical Analysis of Chinese Natural Gas Importing Power Effect
Authors: Li Lingzhi , Zhao Liyun
Published: June 2020

Through the monthly data from 2016 to 2018, this paper studies the Chinese import volume of natural gas and international gas prices, and finds that the change of Chinese natural gas import volume has a great impact on the change of international gas price, and the increase of Chinese natural gas import will promote the growth of international gas price, there is a negative import “big country effect”.