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A method for Improving the Efficiency of Pear Tree Crossbreeding
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作者 Jintao XU Longfei LI +5 位作者 Minghui JI Huan LIU Lijuan GAO Yong GUO Yingjie WANG Baofeng HAO 《Agricultural Biotechnology》 2024年第2期25-26,42,共3页
In view of the short blooming period of pear tree crossbreeding and the complexity of pollination process, a method that can improve the efficiency of crossbreeding of pear trees was provided. Meanwhile, this method c... In view of the short blooming period of pear tree crossbreeding and the complexity of pollination process, a method that can improve the efficiency of crossbreeding of pear trees was provided. Meanwhile, this method can also be applied to the study of pollen xenia effect, pollination tree selection and pure pollen collection in pear tree cultivation. 展开更多
关键词 Pear tree Cross breeding efficiency method
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Research on a TOPSIS energy efficiency evaluation system for crude oil gathering and transportation systems based on a GA-BP neural network 被引量:1
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作者 Xue-Qiang Zhang Qing-Lin Cheng +2 位作者 Wei Sun Yi Zhao Zhi-Min Li 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期621-640,共20页
As the main link of ground engineering,crude oil gathering and transportation systems require huge energy consumption and complex structures.It is necessary to establish an energy efficiency evaluation system for crud... As the main link of ground engineering,crude oil gathering and transportation systems require huge energy consumption and complex structures.It is necessary to establish an energy efficiency evaluation system for crude oil gathering and transportation systems and identify the energy efficiency gaps.In this paper,the energy efficiency evaluation system of the crude oil gathering and transportation system in an oilfield in western China is established.Combined with the big data analysis method,the GA-BP neural network is used to establish the energy efficiency index prediction model for crude oil gathering and transportation systems.The comprehensive energy consumption,gas consumption,power consumption,energy utilization rate,heat utilization rate,and power utilization rate of crude oil gathering and transportation systems are predicted.Considering the efficiency and unit consumption index of the crude oil gathering and transportation system,the energy efficiency evaluation system of the crude oil gathering and transportation system is established based on a game theory combined weighting method and TOPSIS evaluation method,and the subjective weight is determined by the triangular fuzzy analytic hierarchy process.The entropy weight method determines the objective weight,and the combined weight of game theory combines subjectivity with objectivity to comprehensively evaluate the comprehensive energy efficiency of crude oil gathering and transportation systems and their subsystems.Finally,the weak links in energy utilization are identified,and energy conservation and consumption reduction are improved.The above research provides technical support for the green,efficient and intelligent development of crude oil gathering and transportation systems. 展开更多
关键词 Crude oil gathering and transportation system GA-BP neural network Energy efficiency evaluation TOPSIS evaluation method Energy saving and consumption reduction
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Straw return and appropriate tillage method improve grain yield and nitrogen efficiency of winter wheat 被引量:49
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作者 CHEN Jin ZHENG Meng-jing +7 位作者 PANG Dang-wei YIN Yan-ping HAN Ming-ming LI Yan-xia LUO Yong-li XU Xu LI Yong WANG Zhen-lin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第8期1708-1719,共12页
Straw return is an important management tool for tackling and promoting soil nutrient conservation and improving crop yield in Huang-Huai-Hai Plain, China. Although the incorporation of maize straw with deep plowing a... Straw return is an important management tool for tackling and promoting soil nutrient conservation and improving crop yield in Huang-Huai-Hai Plain, China. Although the incorporation of maize straw with deep plowing and rotary tillage practices are widespread in the region, only few studies have focused on rotation tillage. To determine the effects of maize straw return on the nitrogen (N) efficiency and grain yield of winter wheat (Triticum aestivum L.), we conducted experiments in this region for 3 years. Five treatments were tested: (i) rotary tillage without straw return (RT); (ii) deep plowing tillage without straw return (DT); (iii) rotary tillage with total straw return (RS); (iv) deep plowing tillage with total straw return (DS); (v) rotary tillage of 2 years and deep plowing tillage in the 3rd year with total straw return (TS). Treatments with straw return increased kernels no. ear-1, thousand-kernel weight (TKW), grain yields, ratio of dry matter accumulation post-anthesis, and nitrogen (N) efficiency whereas reduced the ears no. ha-1 in the 2011-2012 and 2012-2013 growing seasons. Compared with the rotary tillage, deep plowing tillage significantly increased the grain yield, yield components, total dry matter accumulation, and N efficiency in 2013-2014. RS had significantly higher straw N distribution, soil inorganic nitrogen content, and soil enzymes activities in the 0-10 cm soil layer compared with the DS and TS. However, significantly lower values were ob- served in the 10-20 and 20-30 cm soil layers. TS obtained approximately equal grain yield as DS, and it also reduced the resource costs. Therefore, we conclude that TS is the most economical method for increasing grain yield and N efficiency of winter wheat in Huang-Huai-Hai Plain. 展开更多
关键词 grain yield N efficiency straw return tillage method winter wheat
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The mechanical measuring method of welding heat source efficiency 被引量:1
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作者 张建强 张国栋 +2 位作者 何洁 王承权 陈冰泉 《China Welding》 EI CAS 2007年第4期51-55,共5页
Based on the principle of residual deformation induced by superposition of the welding residual stress and working stress, the welding heat source efficiency has been determined by measuring displacement changes of sp... Based on the principle of residual deformation induced by superposition of the welding residual stress and working stress, the welding heat source efficiency has been determined by measuring displacement changes of specimens under loading and unloading in tensile tests, and combining with calculating welding parameters. Meanwhile, the welding heat source eficiencies obtained are compared with those of the measuring-calculating method. The research results show that the welding heat source efficiencies are almost the same as those obtained by the measuring-calculating method. Therefore, the welding heat source efficiency can be determined accurately by this method, and a new determining method of the heat source efficiency for the welding heat process calculating has been provided. 展开更多
关键词 welding heat source efficiency welding stress welding distortion mechanical measuring-calculating method
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Methods Comparison for Microsatellite Marker Development:Different Isolation Methods,Different Yield Efficiency 被引量:1
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作者 ZHAN Aibin BAO Zhenmin HU Xiaoli LU Wei HU Jingjie 《Journal of Ocean University of China》 SCIE CAS 2009年第2期161-165,共5页
Microsatellite markers have become one kind of the most important molecular tools used in various researches. A large number of microsatellite markers are required for the whole genome survey in the fields of molecula... Microsatellite markers have become one kind of the most important molecular tools used in various researches. A large number of microsatellite markers are required for the whole genome survey in the fields of molecular ecology,quantitative genetics and genomics. Therefore,it is extremely necessary to select several versatile,low-cost,efficient and time-and labor-saving methods to develop a large panel of microsatellite markers. In this study,we used Zhikong scallop(Chlamys farreri) as the target species to compare the efficiency of the five methods derived from three strategies for microsatellite marker development. The results showed that the strategy of constructing small insert genomic DNA library resulted in poor efficiency,while the microsatellite-enriched strategy highly improved the isolation efficiency. Although the mining public database strategy is time-and cost-saving,it is difficult to obtain a large number of microsatellite markers,mainly due to the limited sequence data of non-model species deposited in public databases. Based on the results in this study,we recommend two methods,microsatellite-enriched library construction method and FIASCO-colony hybridization method,for large-scale microsatellite marker development. Both methods were derived from the microsatellite-enriched strategy. The experimental results obtained from Zhikong scallop also provide the reference for microsatellite marker development in other species with large genomes. 展开更多
关键词 MICROSATELLITE marker development isolation efficiency method comparison SCALLOP
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The efficiency and accuracy of probability diagram, spatial statistic and fractal methods in the identification of shear zone gold mineralization: a case study of the Saqqez gold ore district,NW Iran 被引量:1
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作者 Mirmahdi Seyedrahimi-Niaraq Amin Hekmatnejad 《Acta Geochimica》 EI CAS CSCD 2021年第1期78-88,共11页
In this study,geochemical anomaly separation was carried out with methods based on the distribution model,which includes probability diagram(MPD),fractal(concentration-area technique),and U-statistic methods.The main ... In this study,geochemical anomaly separation was carried out with methods based on the distribution model,which includes probability diagram(MPD),fractal(concentration-area technique),and U-statistic methods.The main objective is to evaluate the efficiency and accuracy of the methods in separation of anomalies on the shear zone gold mineralization.For this purpose,samples were taken from the secondary lithogeochemical environment(stream sediment samples)on the gold mineralization in Saqqez,NW of Iran.Interpretation of the histograms and diagrams showed that the MPD is capable of identifying two phases of mineralization.The fractal method could separate only one phase of change based on the fractal dimension with high concentration areas of the Au element.The spatial analysis showed two mixed subpopulations after U=0 and another subpopulation with very high U values.The MPD analysis followed spatial analysis,which shows the detail of the variations.Six mineralized zones detected from local geochemical exploration results were used for validating the methods mentioned above.The MPD method was able to identify the anomalous areas higher than 90%,whereas the two other methods identified 60%(maximum)of the anomalous areas.The raw data without any estimation for the concentration was used by the MPD method using aminimum of calculations to determine the threshold values.Therefore,the MPD method is more robust than the other methods.The spatial analysis identified the detail soft hegeological and mineralization events that were affected in the study area.MPD is recommended as the best,and the spatial U-analysis is the next reliable method to be used.The fractal method could show more detail of the events and variations in the area with asymmetrical grid net and a higher density of sampling or at the detailed exploration stage. 展开更多
关键词 Shear zone gold deposit Modeling of probability diagram method Concentration-area fractal method U-spatial statistics method Phases of efficiency and accuracy mineralization
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Impact of Evaluation of Different Irrigation Methods with Sensor System on Water Consumptive Use and Water Use Efficiency for Maize Yield
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作者 Thamer Thamer Nadine Nassif +1 位作者 Ayad Almaeini Nadhir Al-Ansari 《Journal of Water Resource and Protection》 2021年第11期835-854,共20页
The sensor system is one of the modern and important methods of irrigation management in arid and semi-arid areas, which is water as the limiting factor for crop production. The study was applied for 2016 and 2017 sea... The sensor system is one of the modern and important methods of irrigation management in arid and semi-arid areas, which is water as the limiting factor for crop production. The study was applied for 2016 and 2017 seasons out in Al-Yousifya, 15 km Southwest of Baghdad. A study was conducted to evaluate coefficient uniformity, uniformity distribution and application efficiency for furrow, surface drip and subsurface drip irrigation methods and it was (98, 97 and 89)% and (97, 96 and 88)% for 2016 and 2017 seasons;respectively. And control the volumetric moisture content according to the rhizosphere depth for depths of 10, 20 and 30 cm by means of the sensor system. The results indicated that the height consumptive water use of furrow 707.91 and 689.69 mm<span style="white-space:nowrap;">&middot;</span>season<sup>-1</sup> and the lowest for subsurface drip with emitter deep at 20 cm 313.93 and 293.50 mm<span style="white-space:nowrap;">&middot;</span>season<sup>-1</sup> for 2016 and 2017 seasons;respectively. As well, the highest value of water use efficiency for subsurface in drip irrigation at a depth of 20 cm, was 2.71 and 2.99 kg<span style="white-space:nowrap;">&middot;</span>m<sup>-3</sup> and the lowest value for furrow irrigation was 1.12 and 1.20 kg<span style="white-space:nowrap;">&middot;</span>m<sup>-3</sup> for the 2016 and 2017 seasons;respectively. 展开更多
关键词 Irrigation methods Application efficiency Water Consumptive Use Water Use efficiency MAIZE
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Improved Efficiency Test Method for the Motor Controller with SiC MOSFETs
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作者 Wei Wang Qiang Song +1 位作者 Yiting Li Mukhtiar Ahmad 《Journal of Beijing Institute of Technology》 EI CAS 2020年第3期294-302,共9页
The traditional measurement method was inaccurate to evaluate the motor controller efficiency,which the measurement efficiency value could be more than 100%in practical testing experiments.To deal with this issue,an i... The traditional measurement method was inaccurate to evaluate the motor controller efficiency,which the measurement efficiency value could be more than 100%in practical testing experiments.To deal with this issue,an improved electrical measurement method for the motor controller efficiency is proposed in this paper,which is established by analyzing the power loss distribution and phase currents of the motor controller.It is demonstrated that the SiC MOSFET chips are the main power loss devices in the motor controller,accounting for more than 93.1%of the total power loss.The accuracy of the proposed method is compared with the traditional method in simulation.It shows that the test error of the efficiency obtained by the traditional method fluctuates on a large scale,which varied from 0.094%to 1.911%.Compared with the traditional method,the test error of the proposed method appears to be less than 0.083%,which provides significant guidance for the motor controller efficiency test and design. 展开更多
关键词 electrical measurement method motor controller efficiency power loss distribution SiC MOSFET
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Efficiency and Effectiveness Method versus ε-NTU Method with Application in Finned Flat Tube Compact Heat Exchanger with Water-Ethylene Glycol as Nanofluid Base of Iron Oxide Nanoparticles
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作者 Élcio Nogueira 《Journal of Materials Science and Chemical Engineering》 2022年第2期1-17,共17页
This work aims to establish comparisons between two models used for the performance of heat exchangers. The chosen system, in this case, consists of a heat exchanger used in automotive radiators flat finned tube type.... This work aims to establish comparisons between two models used for the performance of heat exchangers. The chosen system, in this case, consists of a heat exchanger used in automotive radiators flat finned tube type. Water and ethylene glycol compound as base fluid and volume fractions of iron oxide nanoparticles (Fe<sub>3</sub>O<sub>4</sub>) are used as a refrigerant. The quantities determined in this work are the nanofluid exit temperature, the air exit temperature, the absolute error between the models for heat transfer rate, and Effectiveness. The quantities that constitute parameters, independent variables, are the airflow, represented by the Reynolds number, and the iron oxide volume fraction. Ethylene Glycol 50% compound has slightly better thermal performance than pure water and reduces the reactive effect of water on the environment, increasing the average life of the equipment. The absolute relative error between the models is less than 20% and presents maximum values with the increase of the nanoparticle volume fraction and growth in the Reynolds number for the air. 展开更多
关键词 efficiency and Effectiveness method ε-NTU method Compact Heat Exchanger Iron Oxid Nanoparticles NANOFLUID
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Evaluation of the operation efficiency of maternity insurance fund --based on DEA method
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作者 ZHANG Haizhu 《International English Education Research》 2018年第3期53-55,共3页
Maternity insurance fund is an important part of social insurance fund. It plays an important role in safeguarding the rights and interests of pregnant women and improving the welfare of women. With the expansion of t... Maternity insurance fund is an important part of social insurance fund. It plays an important role in safeguarding the rights and interests of pregnant women and improving the welfare of women. With the expansion of the balance of the birth insurance fund, the balance of income and expenditure has become a difficult goal to be reached. Therefore, this paper aims to evaluate the operating efficiency of the birth insurance fund, discover the problems of the birth insurance system, and put forward some suggestions to improve the efficiency of the birth insurance fund and promote the perfection of the birth insurance. 展开更多
关键词 fertility insurance fund efficiency assessment DEA method
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To Improve Learning Efficiency,Try This Method
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作者 Adela 《新世纪智能》 2018年第17期71-72,共2页
The key to learning a new motor skill—such as playing the piano or mastering a new sport—isn’t necessarily how many hours you spend practising,but the way you practise,according to a 2016 study.Scientists have foun... The key to learning a new motor skill—such as playing the piano or mastering a new sport—isn’t necessarily how many hours you spend practising,but the way you practise,according to a 2016 study.Scientists have found that by subtly varying your training, you can keep your brain more active throughout the learning process, and halve the time it takes to get up to scratch. 展开更多
关键词 LEARNING efficiency TRY This method
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Filtering-efficiency measurement of Chinese-made filter 1by double-filter method
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作者 ZHI Min (Shanghai Institute of Nuclear Rcsearrh, the Chinese Academy of Sciences, Shanghai 201800) 《Nuclear Science and Techniques》 SCIE CAS CSCD 1999年第3期168-170,共3页
Filtering efficiency of the Chinese-made filter 1 has been measured by the double-filter method with only one set of measurement equipment. The β counts of the two filters are measured in turn for every 3 minutes, fr... Filtering efficiency of the Chinese-made filter 1 has been measured by the double-filter method with only one set of measurement equipment. The β counts of the two filters are measured in turn for every 3 minutes, from which the decay constants are extracted to be 0.0131 min-1 and 0.0129 min-1 for the first and second filter respectively. After correcting the β counts of the second filter, the filtering efficiency of the filter is obtained to be (87.4±0.7)% in average. 展开更多
关键词 滤波器 双重滤波方法 滤波效率
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Benchmarking of energy efficiency standards for residential buildings in China
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作者 陈华 李慧玲 《Journal of Southeast University(English Edition)》 EI CAS 2010年第2期151-155,共5页
In order to benchmark the energy efficiency standards for residential buildings in China,the Hong Kong building environment assessment method(HK-BEAM)is chosen as the compliance criteria for assessment.The annual en... In order to benchmark the energy efficiency standards for residential buildings in China,the Hong Kong building environment assessment method(HK-BEAM)is chosen as the compliance criteria for assessment.The annual energy consumption and the overall thermal transfer value(OTTV)of a baseline residential building prescribed in the Chinese codes and the HK-BEAM are evaluated and compared by the energy budget approach.The results show that in the Chinese codes,the OTTV of the residential building is lower,but the annual energy consumption and the cooling load are higher than those in the HK-BEAM.The annual energy use difference amounts to 13.4%.All the compliance criteria except the ventilation rate and the equipment power in the Chinese codes are set higher than those in the HK-BEAM.However,the compliance criteria of the ventilation rate and the equipment power,especially the ventilation rate,result in much energy consumption,which ultimately induces a high energy budget for residential buildings. 展开更多
关键词 Chinese energy efficiency code Hong Kong building environment assessment method(HK-BEAM) energy budget approach residential buildings
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Modeling screening efficiency with vibrational parameters based on DEM 3D simulation 被引量:14
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作者 CHEN Yanhua TONG Xin 《Mining Science and Technology》 EI CAS 2010年第4期615-620,共6页
The efficiency of particle screening was studied over a range of vibrational parameters including amplitude, frequency and vibrational direction. The Discrete Element Method (DEM) was used to simulate the screening pr... The efficiency of particle screening was studied over a range of vibrational parameters including amplitude, frequency and vibrational direction. The Discrete Element Method (DEM) was used to simulate the screening process. A functional relationship between efficiency and the parameters, both singly and combined, is established. The function is a complicated exponential. Optimal amplitude and frequency values are smaller for particles near the mesh and larger for other particles. The optimum vibration angle is 45° for nearly all kinds of particles. A transverse velocity, V⊥, was defined and V⊥=0.2 m/s was identified to be the most efficient operating point by both simulation and experimental observation. Comparison of these results with those reported by others is included. 展开更多
关键词 MODELING screening efficiency discrete element method simulations
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High Efficient Methods of Content-based 3D Model Retrieval 被引量:5
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作者 WU Yuanhao TIAN Ling LI Chenggang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第2期248-256,共9页
Content-based 3D model retrieval is of great help to facilitate the reuse of existing designs and to inspire designers during conceptual design. However, there is still a gap to apply it in industry due to the low tim... Content-based 3D model retrieval is of great help to facilitate the reuse of existing designs and to inspire designers during conceptual design. However, there is still a gap to apply it in industry due to the low time efficiency. This paper presents two new methods with high efficiency to build a Content-based 3D model retrieval system. First, an improvement is made on the "Shape Distribution (D2)" algorithm, and a new algorithm named "Quick D2" is proposed. Four sample 3D mechanical models are used in an experiment to compare the time cost of the two algorithms. The result indicates that the time cost of Quick D2 is much lower than that of D2, while the descriptors extracted by the two algorithms are almost the same. Second, an expandable 3D model repository index method with high performance, namely, RBK index, is presented. On the basis of RBK index, the search space is pruned effectively during the search process, leading to a speed up of the whole system. The factors that influence the values of the key parameters of RBK index are discussed and an experimental method to find the optimal values of the key parameters is given. Finally, "3D Searcher", a content-based 3D model retrieval system is developed. By using the methods proposed, the time cost for the system to respond one query online is reduced by 75% on average. The system has been implemented in a manufacturing enterprise, and practical query examples during a case of the automobile rear axle design are also shown. The research method presented shows a new research perspective and can effectively improve the content-based 3D model retrieval efficiency. 展开更多
关键词 3D model retrieval high efficient methods shape descriptor extraction model repository index
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The Synthetic Evaluation of Warhead Overall Efficiency 被引量:3
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作者 Gu Xiaohui & Cao Bing College of Mechanics, Nanjing University of Science & Technology, Nanjing 210094, P. R. China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2003年第1期12-17,共6页
The evaluation system of smart ammunition warhead overall efficiency has been established in this paper. Allkinds of evaluation methods have been analyzed. Having led the concept of hierarchical structure into techniq... The evaluation system of smart ammunition warhead overall efficiency has been established in this paper. Allkinds of evaluation methods have been analyzed. Having led the concept of hierarchical structure into technique for orderpreference by similarity to ideal solution (TOPSIS) method, we put forward the step TOPSIS method which is suitable forevaluating the overall efficiency of smart ammunition warheads. In the calculation of index weight, the graded weight cal-culus is put forward which hardly relies on the subjectivity of decision-makers and can reflect the sensitivity and compatibili-ty of the index. In the graded weight calculation, the proportional-arithmetic weight value calculus and sensitivity-compati-bility weight value calculus are given respectively. 展开更多
关键词 Step analysis TOPSIS method WARHEAD efficiency evaluation.
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Sampling Methods for Efficient Training of Graph Convolutional Networks:A Survey 被引量:5
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作者 Xin Liu Mingyu Yan +3 位作者 Lei Deng Guoqi Li Xiaochun Ye Dongrui Fan 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2022年第2期205-234,共30页
Graph convolutional networks(GCNs)have received significant attention from various research fields due to the excellent performance in learning graph representations.Although GCN performs well compared with other meth... Graph convolutional networks(GCNs)have received significant attention from various research fields due to the excellent performance in learning graph representations.Although GCN performs well compared with other methods,it still faces challenges.Training a GCN model for large-scale graphs in a conventional way requires high computation and storage costs.Therefore,motivated by an urgent need in terms of efficiency and scalability in training GCN,sampling methods have been proposed and achieved a significant effect.In this paper,we categorize sampling methods based on the sampling mechanisms and provide a comprehensive survey of sampling methods for efficient training of GCN.To highlight the characteristics and differences of sampling methods,we present a detailed comparison within each category and further give an overall comparative analysis for the sampling methods in all categories.Finally,we discuss some challenges and future research directions of the sampling methods. 展开更多
关键词 efficient training graph convolutional networks(GCNs) graph neural networks(GNNs) sampling method
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Screening efficiency and screen length of a linear vibrating screen using DEM 3D simulation 被引量:20
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作者 Wang Guifeng Tong Xin 《Mining Science and Technology》 EI CAS 2011年第3期451-455,共5页
The effect of screen length on the screening efficiency of particles is studied under various single parameter conditions including frequency, amplitude, vibration angle, and screen inclination. The Discrete Element M... The effect of screen length on the screening efficiency of particles is studied under various single parameter conditions including frequency, amplitude, vibration angle, and screen inclination. The Discrete Element Method (DEM) has been used to simulate the screening process. A functional relationship between screening efficiency and screen length is established. It is shown that screening efficiency and screen length have a complicated exponential relationship. Relationships between them are profoundly discussed and conclusions are easily drawn: low values of the parameters do not benefit screening; screening efficiency generally increases with screen length; screening efficiency reaches a plateau when these parameters are in range frequently encountered in practical applications. 展开更多
关键词 Screen lengthScreening efficiency Discrete element method
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Influence of alkyl group of imidazolinyl-quaternary-ammonium-salt on corrosion inhibition efficiency 被引量:3
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作者 石顺存 王学业 +3 位作者 易平贵 曹晨忠 邓彤彤 苏界殊 《Journal of Central South University of Technology》 EI 2006年第4期393-398,共6页
The action between imidazolinyl-quaternary-ammonium-salt(IQAS) molecule and Fe atom was studied, and the influence of the alkyl group connected with N atom of imidazoline ring on corrosion inhibition efficiency was ex... The action between imidazolinyl-quaternary-ammonium-salt(IQAS) molecule and Fe atom was studied, and the influence of the alkyl group connected with N atom of imidazoline ring on corrosion inhibition efficiency was explored. Quantum chemical methods, HF/6-31 G and HF/Lan L2 dz, were applied successively to calculate the parameters such as front molecular orbit energy of IQASⅠ-Ⅳ and chemical adsorption for IQASⅠ-Ⅳ and Fe atom. The corrosion inhibition efficiency was measured with the weight loss method of carbon steel samples in acidic solution and oil field sewage. Based on the theoretical analyses and experimental results, it is concluded that N-Fe coordination bond is formed between IQAS molecule and Fe atom, corrosion inhibition efficiency is decreased in the following order(from large to small): IQAS Ⅳ, IQAS Ⅲ, IQAS Ⅱ, IQASⅠ. 展开更多
关键词 imidazolinyl-quaternary-ammonium-salt corrosion inhibition efficiency quantum chemistry weight loss method
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Axial response and material efficiency of tapered helical piles 被引量:4
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作者 Hamid Mortazavi Bak Amir M.Halabian +1 位作者 Hamid Hashemolhosseini Mohammadali Rowshanzamir 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2021年第1期176-187,共12页
Different techniques have been proposed to increase the bearing capacity of open-ended piles.Welding helices to the shaft and tapering the pile shaft could be used simultaneously to enhance the static and dynamic beha... Different techniques have been proposed to increase the bearing capacity of open-ended piles.Welding helices to the shaft and tapering the pile shaft could be used simultaneously to enhance the static and dynamic behaviors of these piles.This paper subjects the bearing capacity,stiffness,frictional behavior,and material efficiency of the tapered helical piles to scrutiny.Tapered helical piles are introduced herein as an alternative option to improve the material efficiency of hollow piles.Based on the Taguchi method,a series of experiments was designed and conducted.The axial responses of tapered helical piles are also investigated using finite element analyses.The results derived from loadedisplacement curves and strain gages are used to characterize the axial compression responses of tapered helical piles.The effects of tapered angle,helices diameter and helices distance are examined using dimensionless parameters,and the degree of contribution of these factors is calculated on each of the enumerated variables individually.Experimental results show that the shaft friction resistance of tapered helical piles increases continuously with the pile head settlement.Furthermore,the effect of tapered wall on the shaft friction resistance is more tangible at low stress levels.The results showed that the relative material efficiency factor of the optimum pile could be 2.5 times that of unoptimized pile with a similar quantity of material. 展开更多
关键词 Tapered helical pile Axial response Bearing capacity Shaft resistance Initial tangent stiffness Relative material efficiency Taguchi method
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