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Comparison of Manual and Automatic Methods for Measurement of Methane Emission from Rice Paddy Fields 被引量:28
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作者 郑循华 王明星 +2 位作者 王跃思 沈壬兴 李晶 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1998年第4期139-149,共11页
S The methane emission flux from rice paddies was simultaneously measured with automatic and manual methods in the suburban of Suzhou. Both methods were based on the static chamber/GC-FID techniques. Detail analysi... S The methane emission flux from rice paddies was simultaneously measured with automatic and manual methods in the suburban of Suzhou. Both methods were based on the static chamber/GC-FID techniques. Detail analysis of the experimental results indicates: a) The data of methane emission measured with the automatic method is reliable. b) About 11 or 19 o′clock of local time is recommended as the optimum sampling time for the manual spot measurement of methane emission from rice paddies. The methane emission fluxes measured by manual sampling at local time other than the optimum time have to be corrected. The correction coefficient may be determined by automatic and continuous measurement. c) In order to get a more accurate result, an empirical correction factor, such as 18%, is recommended to correct the seasonally total amount of measured methane emission by enlarging the automatically measured data or reducing the manually measured ones. 展开更多
关键词 Methane emission automatic method Manual method Rice paddy
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A Computer Program for Automatic Watering Based on Potential Evapotranspiration by Penman Method and Predicted Leaf Area in Miniature Pot Rose Production 被引量:2
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作者 YU Wen-jin Kitamura Ryo +2 位作者 Kato Katsuhiko LI Lian-hua Fukui Hirokazu 《Agricultural Sciences in China》 CAS CSCD 2010年第3期370-377,共8页
In this study, we developed a computer program for automatic prediction of watering time point by considering the environmental factors such as solar radiation, air temperature and relative humidity based on the multi... In this study, we developed a computer program for automatic prediction of watering time point by considering the environmental factors such as solar radiation, air temperature and relative humidity based on the multiple linear regression equation of leaf area and Penman Method. The experiments were carried out for a year in two watering experimental plots, one of which was controlled by pF value, and the other by the computer program. After comparing the results of the two plots, the following findings were obtained. In the computer program plot, the observed and predicted values of both leaf area and evapotranspiration indicated significant correlation at the 1% level, which suggested that the computer program had high prediction accuracy. In addition, no significant difference was observed between the two experimental plots with respects to the plant height, plant diameter, leaf area, leaf number, fresh weight, and dry weight, which demonstrated that the plants in the computer program plot had normal growth. On the other hand, although the number of flower buds and flowering shoots showed higher values at the end of certain cultivations in the computer program plot than those in pF value plot, we proposed that it was due to the effect of cumulative daily solar radiation in the greenhouse, rather than the watering. Thus, we have reached the conclusion that the computer program for automatic prediction of watering time point developed by this study has high applicability in miniature pot rose production. 展开更多
关键词 automatic watering leaf area miniature pot rose Penman method program
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Identification method of crowded passenger flow based on automatic fare collection data of Nanjing Metro 被引量:2
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作者 Lu Jia Ren Gang Xu Linghui 《Journal of Southeast University(English Edition)》 EI CAS 2019年第2期236-241,共6页
To relieve traffic congestion in urban rail transit stations,a new identification method of crowded passenger flow based on automatic fare collection data is proposed.First,passenger travel characteristics are analyze... To relieve traffic congestion in urban rail transit stations,a new identification method of crowded passenger flow based on automatic fare collection data is proposed.First,passenger travel characteristics are analyzed by observing the temporal distribution of inflow passengers each hour and the spatial distribution concerning cross-section passenger flow.Secondly,the identification method of crowded passenger flow is proposed to calculate the threshold via the probability density function fitted by Matlab and classify the early-warning situation based on the threshold obtained.Finally,a case study of Xinjiekou station is conducted to prove the validity and practicability of the proposed method.Compared to the traditional methods,the proposed comprehensive method can remove defects such as efficiency and delay.Furthermore,the proposed method is suitable for other rail transit companies equipped with automatic fare collection systems. 展开更多
关键词 travel characteristic identification method crowded passenger flow automatic fare collection
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Investigation of Automatic Speech Recognition Systems via the Multilingual Deep Neural Network Modeling Methods for a Very Low-Resource Language, Chaha 被引量:1
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作者 Tessfu Geteye Fantaye Junqing Yu Tulu Tilahun Hailu 《Journal of Signal and Information Processing》 2020年第1期1-21,共21页
Automatic speech recognition (ASR) is vital for very low-resource languages for mitigating the extinction trouble. Chaha is one of the low-resource languages, which suffers from the problem of resource insufficiency a... Automatic speech recognition (ASR) is vital for very low-resource languages for mitigating the extinction trouble. Chaha is one of the low-resource languages, which suffers from the problem of resource insufficiency and some of its phonological, morphological, and orthographic features challenge the development and initiatives in the area of ASR. By considering these challenges, this study is the first endeavor, which analyzed the characteristics of the language, prepared speech corpus, and developed different ASR systems. A small 3-hour read speech corpus was prepared and transcribed. Different basic and rounded phone unit-based speech recognizers were explored using multilingual deep neural network (DNN) modeling methods. The experimental results demonstrated that all the basic phone and rounded phone unit-based multilingual models outperformed the corresponding unilingual models with the relative performance improvements of 5.47% to 19.87% and 5.74% to 16.77%, respectively. The rounded phone unit-based multilingual models outperformed the equivalent basic phone unit-based models with relative performance improvements of 0.95% to 4.98%. Overall, we discovered that multilingual DNN modeling methods are profoundly effective to develop Chaha speech recognizers. Both the basic and rounded phone acoustic units are convenient to build Chaha ASR system. However, the rounded phone unit-based models are superior in performance and faster in recognition speed over the corresponding basic phone unit-based models. Hence, the rounded phone units are the most suitable acoustic units to develop Chaha ASR systems. 展开更多
关键词 automatic SPEECH Recognition MULTILINGUAL DNN Modeling methods Basic PHONE ACOUSTIC UNITS Rounded PHONE ACOUSTIC UNITS Chaha
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Method of Predicting Water Content in Crude Oil Based on Measuring Range Automatic Switching
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作者 陈祥光 朱文博 +1 位作者 赵军 任磊 《Journal of Beijing Institute of Technology》 EI CAS 2010年第1期87-91,共5页
Water content in output crude oil is hard to measure precisely because of wide range of dielectric coefficient of crude oil caused by injected dehydrating and demulsifying agents.The method to reduce measurement error... Water content in output crude oil is hard to measure precisely because of wide range of dielectric coefficient of crude oil caused by injected dehydrating and demulsifying agents.The method to reduce measurement error of water content in crude oil proposed in this paper is based on switching measuring ranges of on-line water content analyzer automatically.Measuring precision on data collected from oil field and analyzed by in-field operators can be impressively improved by using back propogation (BP) neural network to predict water content in output crude oil.Application results show that the difficulty in accurately measuring water-oil content ratio can be solved effectively through this combination of on-line measuring range automatic switching and real time prediction,as this method has been tested repeatedly on-site in oil fields with satisfactory prediction results. 展开更多
关键词 water content in crude oil prediction method BP network measuring range automatic switching
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Study on Rear-end Real-time Data Quality Control Method of Regional Automatic Weather Station
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作者 WANG Chao-qiu 《Meteorological and Environmental Research》 CAS 2011年第9期6-8,12,共4页
[Objective] The aim was to study the rear-end real-time data quality control method of regional automatic weather station. [Method] The basic content and steps of rear-end real-time data quality control of regional au... [Objective] The aim was to study the rear-end real-time data quality control method of regional automatic weather station. [Method] The basic content and steps of rear-end real-time data quality control of regional automatic weather station were introduced. Each element was treated with systematic quality control procedure. The existence of rear-end real time data of regional meteorological station in Guangxi was expounded. Combining with relevant elements and linear changes, improvement based on traditional quality control method was made. By dint of evaluation and relevant check of element, the quality of temperature and pressure was controlled. [Result] The method was optimized based on traditional quality control method, and it narrowed the effectiveness of real-time data quality control. The quality check of hourly precipitation applied relevant check of hourly minimum temperature, vertical consistency check of radar data, which can effectively improve the accuracy and credibility of hourly precipitation quality control. [Conclusion] The method was on trial for one year in the quality control of real-time data in the regional automatic meteorological station in Guangxi and had gained good outcome. 展开更多
关键词 Regional automatic stations Real-time data Quality control method research China
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An inverse analysis of fluid flow through granular media using differentiable lattice Boltzmann method 被引量:1
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作者 Qiuyu Wang Krishna Kumar 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2077-2090,共14页
This study presents a method for the inverse analysis of fluid flow problems.The focus is put on accurately determining boundary conditions and characterizing the physical properties of granular media,such as permeabi... This study presents a method for the inverse analysis of fluid flow problems.The focus is put on accurately determining boundary conditions and characterizing the physical properties of granular media,such as permeability,and fluid components,like viscosity.The primary aim is to deduce either constant pressure head or pressure profiles,given the known velocity field at a steady-state flow through a conduit containing obstacles,including walls,spheres,and grains.The lattice Boltzmann method(LBM)combined with automatic differentiation(AD)(AD-LBM)is employed,with the help of the GPU-capable Taichi programming language.A lightweight tape is used to generate gradients for the entire LBM simulation,enabling end-to-end backpropagation.Our AD-LBM approach accurately estimates the boundary conditions for complex flow paths in porous media,leading to observed steady-state velocity fields and deriving macro-scale permeability and fluid viscosity.The method demonstrates significant advantages in terms of prediction accuracy and computational efficiency,making it a powerful tool for solving inverse fluid flow problems in various applications. 展开更多
关键词 Inverse problem Fluid flow Granular media automatic differentiation(AD) Lattice Boltzmann method(LBM)
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Automatic Diagnosis of Polycystic Ovarian Syndrome Using Wrapper Methodology with Deep Learning Techniques
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作者 Mohamed Abouhawwash S.Sridevi +3 位作者 Suma Christal Mary Sundararajan Rohit Pachlor Faten Khalid Karim Doaa Sami Khafaga 《Computer Systems Science & Engineering》 SCIE EI 2023年第10期239-253,共15页
One of the significant health issues affecting women that impacts their fertility and results in serious health concerns is Polycystic ovarian syndrome(PCOS).Consequently,timely screening of polycystic ovarian syndrom... One of the significant health issues affecting women that impacts their fertility and results in serious health concerns is Polycystic ovarian syndrome(PCOS).Consequently,timely screening of polycystic ovarian syndrome can help in the process of recovery.Finding a method to aid doctors in this procedure was crucial due to the difficulties in detecting this condition.This research aimed to determine whether it is possible to optimize the detection of PCOS utilizing Deep Learning algorithms and methodologies.Additionally,feature selection methods that produce the most important subset of features can speed up calculation and enhance the effectiveness of classifiers.In this research,the tri-stage wrapper method is used because it reduces the computation time.The proposed study for the Automatic diagnosis of PCOS contains preprocessing,data normalization,feature selection,and classification.A dataset with 39 characteristics,including metabolism,neuroimaging,hormones,and biochemical information for 541 subjects,was employed in this scenario.To start,this research pre-processed the information.Next for feature selection,a tri-stage wrapper method such as Mutual Information,ReliefF,Chi-Square,and Xvariance is used.Then,various classification methods are tested and trained.Deep learning techniques including convolutional neural network(CNN),multi-layer perceptron(MLP),Recurrent neural network(RNN),and Bi long short-term memory(Bi-LSTM)are utilized for categorization.The experimental finding demonstrates that with effective feature extraction process using tri stage wrapper method+CNN delivers the highest precision(97%),high accuracy(98.67%),and recall(89%)when compared with other machine learning algorithms. 展开更多
关键词 Deep learning automatic detection polycystic ovarian syndrome tri-stage wrapper method mutual information RELIEF CHI-SQUARE
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Insertion of Ontological Knowledge to Improve Automatic Summarization Extraction Methods
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作者 Jésus Antonio Motta Laurence Capus Nicole Tourigny 《Journal of Intelligent Learning Systems and Applications》 2011年第3期131-138,共8页
The vast availability of information sources has created a need for research on automatic summarization. Current methods perform either by extraction or abstraction. The extraction methods are interesting, because the... The vast availability of information sources has created a need for research on automatic summarization. Current methods perform either by extraction or abstraction. The extraction methods are interesting, because they are robust and independent of the language used. An extractive summary is obtained by selecting sentences of the original source based on information content. This selection can be automated using a classification function induced by a machine learning algorithm. This function classifies sentences into two groups: important or non-important. The important sentences then form the summary. But, the efficiency of this function directly depends on the used training set to induce it. This paper proposes an original way of optimizing this training set by inserting lexemes obtained from ontological knowledge bases. The training set optimized is reinforced by ontological knowledge. An experiment with four machine learning algorithms was made to validate this proposition. The improvement achieved is clearly significant for each of these algorithms. 展开更多
关键词 automatic SUMMARIZATION ONTOLOGY MACHINE Learning Extraction method
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Test Method for Evaluating the Cleaning Performance of Proteases in Automatic Dishwashing Detergent
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作者 Xu Lu Ji Jing Pieter Augustinus 《China Detergent & Cosmetics》 2021年第2期69-73,共5页
A test method was developed to better evaluate the cleaning performance of protease in Chinese automatic dishwashing detergent(ADD)and differentiate the washing performance of different ADD formulations on protein sta... A test method was developed to better evaluate the cleaning performance of protease in Chinese automatic dishwashing detergent(ADD)and differentiate the washing performance of different ADD formulations on protein stains.Steamed egg stain,which was a Chinese-consumers-relevant soil,was used as monitor.The response curves of the stain to different amounts of protease were measured under laboratory conditions,and the stain removal ability of commercially available ADDs was tested with this method.The results showed that the soil removal rate of ADD without protease was less than 10%,and the soil removal rate increased with the increase of protease dosage in the range of 0~2.0%.Steamed egg stain had a good response to protease,and it could effectively distinguish the cleaning performance of commercial ADDs.The test method could be used in the development,screening and evaluation of ADD formulations. 展开更多
关键词 PROTEASE automatIC dishwashing DETERGENT stain REMOVAL TEST method
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Research on Verification Method of Motor Startups in Nuclear Power Plants Based on Topology Recognition
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作者 Li Baozhu Dong Weijie Chen Chao 《系统仿真学报》 CAS CSCD 北大核心 2024年第12期2813-2823,共11页
There are many motors in operation or on standby in nuclear power plants,and the startup of group motors will have a great impact on the voltage of the emergency bus.At present,there is no special or inexpensive softw... There are many motors in operation or on standby in nuclear power plants,and the startup of group motors will have a great impact on the voltage of the emergency bus.At present,there is no special or inexpensive software to solve this problem,and the experience of engineers is not accurate enough.Therefore,this paper developed a method and system for the startup calculation of group motors in nuclear power plants and proposed an automatic generation method of circuit topology in nuclear power plants.Each component in the topology was given its unique number,and the component class could be constructed according to its type and upper and lower connections.The subordination and topology relationship of switches,buses,and motors could be quickly generated by the program according to the component class,and the simplified direct power flow algorithm was used to calculate the power flow for the startup of group motors according to the above relationship.Then,whether the bus voltage is in the safe range and whether the voltage exceeds the limit during the startup of the group motor could be judged.The practical example was used to verify the effectiveness of the method.Compared with other professional software,the method has high efficiency and low cost. 展开更多
关键词 power supply for nuclear power plant automatic topology recognition startup of group motor simplified direct power flow algorithm verification method
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Study on the automatic process of line heating for pillow shape plate 被引量:3
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作者 WANG Ji LIU Yu-jun JI Zhuo-shang DENG Yan-ping GUO Pei-jun ZHOU Bo 《Journal of Marine Science and Application》 2006年第1期31-38,共8页
This paper focuses on the process for pillow shape plate by line heating technique, which is widely applied in the production of ship hull. Based on the analysis of primary parameters and experimental data in line hea... This paper focuses on the process for pillow shape plate by line heating technique, which is widely applied in the production of ship hull. Based on the analysis of primary parameters and experimental data in line heating process, the amount of local contraction generated by line heating has been illustrated. Then, combining with the computational result of local deformation determined by shell plate development, an optimization method for line heating parameters has been studied. This prediction system may provide rational arrangements of heating lines and technical parameters of process. By integrating the prediction system into the line heating robot for pillow shape plate, the automatic process of line heating for pillow shape plate can be achieved. 展开更多
关键词 line heating pillow shape plate prediction method automatic process
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Automatic identification of rock discontinuity and stability analysis of tunnel rock blocks using terrestrial laser scanning 被引量:4
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作者 Meng Wang Jiawen Zhou +3 位作者 Junlin Chen Nan Jiang Puwen Zhang Haibo Li 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第7期1810-1825,共16页
Local geometric information and discontinuity features are key aspects of the analysis of the evolution and failure mechanisms of unstable rock blocks in rock tunnels.This study demonstrates the integration of terrest... Local geometric information and discontinuity features are key aspects of the analysis of the evolution and failure mechanisms of unstable rock blocks in rock tunnels.This study demonstrates the integration of terrestrial laser scanning(TLS)with distinct element method for rock mass characterization and stability analysis in tunnels.TLS records detailed geometric information of the surrounding rock mass by scanning and collecting the positions of millions of rock surface points without contact.By conducting a fuzzy K-means method,a discontinuity automatic identification algorithm was developed,and a method for obtaining the geometric parameters of discontinuities was proposed.This method permits the user to visually identify each discontinuity and acquire its spatial distribution features(e.g.occurrences,spac-ings,trace lengths)in great detail.Compared with hand mapping in conventional geotechnical surveys,the geometric information of discontinuities obtained by this approach is more accurate and the iden-tification is more efficient.Then,a discrete fracture network with the same statistical characteristics as the actual discontinuities was generated with the distinct element method,and a representative nu-merical model of the jointed surrounding rock mass was established.By means of numerical simulation,potential unstable rock blocks were assessed,and failure mechanisms were analyzed.This method was applied to detection and assessment of unstable rock blocks in the spillway and sand flushing tunnel of the Hongshiyan hydropower project after a collapse.The results show that the noncontact detection of blocks was more labor-saving with lower safety risks compared with manual surveys,and the stability assessment was more reliable since the numerical model built by this method was more consistent with the distribution characteristics of actual joints.This study can provide a reference for geological survey and unstable rock block hazard mitigation in tunnels subjected to complex geology and active rockfalls. 展开更多
关键词 Rock tunnel Terrestrial laser scanning(TLS) Discontinuity automatic identification Distinct element method Rock block stability assessment
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CitationAS: A Tool of Automatic Survey Generation Based on Citation Content 被引量:1
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作者 jie wang chengzhi zhang +1 位作者 mengying zhang sanhong deng 《Journal of Data and Information Science》 CSCD 2018年第2期20-37,共18页
Purpose: This study aims to build an automatic survey generation tool, named CitationAS, based on citation content as represented by the set of citing sentences in the original articles.Design/methodology/approach: ... Purpose: This study aims to build an automatic survey generation tool, named CitationAS, based on citation content as represented by the set of citing sentences in the original articles.Design/methodology/approach: Firstly, we apply LDA to analyse topic distribution of citation content. Secondly, in CitationAS, we use bisecting K-means, Lingo and STC to cluster retrieved citation content. Then Word2Vec, Word Net and combination of them are applied to generate cluster labels. Next, we employ TF-IDF, MMR, as well as considering sentence location information, to extract important sentences, which are used to generate surveys. Finally, we adopt manual evaluation for the generated surveys.Findings: In experiments, we choose 20 high-frequency phrases as search terms. Results show that Lingo-Word2Vec, STC-Word Net and bisecting K-means-Word2Vec have better clustering effects. In 5 points evaluation system, survey quality scores obtained by designing methods are close to 3, indicating surveys are within acceptable limits. When considering sentence location information, survey quality will be improved. Combination of Lingo, Word2Vec, TF-IDF or MMR can acquire higher survey quality.Research limitations: The manual evaluation method may have a certain subjectivity. We use a simple linear function to combine Word2Vec and Word Net that may not bring out their strengths. The generated surveys may not contain some newly created knowledge of some articles which may concentrate on sentences with no citing.Practical implications: CitationAS tool can automatically generate a comprehensive, detailed and accurate survey according to user’s search terms. It can also help researchers learn about research status in a certain field.Originality/value: Citaiton AS tool is of practicability. It merges cluster labels from semantic level to improve clustering results. The tool also considers sentence location information when calculating sentence score by TF-IDF and MMR. 展开更多
关键词 automatic survey system Citation content Clustering algorithms Labelgeneration approaches Sentence extraction methods
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Configuration Synthesis and Performance Analysis of 9‑Speed Automatic Transmissions 被引量:1
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作者 Huafeng Ding Changwang Cai +2 位作者 Ziming Chen Tao Ke Bowen Mao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2020年第3期97-117,共21页
Current research of automatic transmission(AT)mainly focuses on the improvement of driving performance,and configuration innovation is one of the main research directions.However,finding new configurations of ATs is o... Current research of automatic transmission(AT)mainly focuses on the improvement of driving performance,and configuration innovation is one of the main research directions.However,finding new configurations of ATs is one of the main limitations of configuration innovation.In the present study,epicyclic gear trains(EGTs)are applied to investigate mechanisms of 9-speed ATs.Then four kinematic configurations are proposed for automatic transitions.In order to evaluate the performance of proposed mechanisms,the lever analogy method is applied to conduct kinematic and mechanical analyses.The power flow analysis is conducted,and then transmission efficiencies are calculated based on the torque method.The comparative analysis between the proposed and existing mechanisms is carried out where obtained results show that proposed mechanisms have reasonable performance and can be used in ATs.The prototype of an AT is manufactured and the speed test is conducted,which proves the accuracy of analysis and the feasibility of proposed mechanisms. 展开更多
关键词 automatic transmission Epicyclic gear train Lever analogy Gear ratio Torque method
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Numerical and Experimental Analysis of A Ducted Propeller Designed by A Fully Automated Optimization Process Under Open Water Condition 被引量:1
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作者 余龙 Markus DRUCKENBROD +2 位作者 Martin GREVE 王珂琦 Moustafa ABDEL-MAKSOUD 《China Ocean Engineering》 SCIE EI CSCD 2015年第5期733-744,共12页
A fully automated optimization process is provided for the design of ducted propellers under open water conditions, including 3D geometry modeling, meshing, optimization algorithm and CFD analysis techniques. The deve... A fully automated optimization process is provided for the design of ducted propellers under open water conditions, including 3D geometry modeling, meshing, optimization algorithm and CFD analysis techniques. The developed process allows the direct integration of a RANSE solver in the design stage. A practical ducted propeller design case study is carried out for validation. Numerical simulations and open water tests are fulfilled and proved that the optimum ducted propeller improves hydrodynamic performance as predicted. 展开更多
关键词 ducted propeller optimum design RANSE solver automatic optimization method
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RESEARCH ON AUTOMATIC FOG IDENTIFICATION TECHNOLOGY BY METEOROLOGICAL SATELLITE REMOTE SENSING 被引量:1
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作者 周红妹 葛伟强 +2 位作者 柏桦 刘冬韡 杨引明 《Journal of Tropical Meteorology》 SCIE 2009年第1期28-37,共10页
There is an urgent need for the development of a method that can undertake rapid, effective, and accurate monitoring and identification of fog by satellite remote sensing, since heavy fog can cause enormous disasters ... There is an urgent need for the development of a method that can undertake rapid, effective, and accurate monitoring and identification of fog by satellite remote sensing, since heavy fog can cause enormous disasters to China’s national economy and people's lives and property in the urban and coastal areas. In this paper, the correlative relationship between the reflectivity of land surface and clouds in different time phases is found, based on the analysis of the radiative and satellite-based spectral characteristics of fog. Through calculation and analyses of the relative variability of the reflectivity in the images, the threshold to identify quasi-fog areas is generated automatically. Furthermore, using the technique of quick image run-length encoding, and in combination with such practical methods as analyzing texture and shape fractures, smoothness, and template characteristics, the automatic identification of fog and fog-cloud separation using meteorological satellite remote sensing images are studied, with good results in application. 展开更多
关键词 meteorological satellites remote sensing fog dynamic monitoring rapid and automatic identification methods
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MODEL AND METHOD OF WELL TEST ANALYSIS FORWELLS WITH VERTICAL FRACTURE
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作者 郭大立 曾晓慧 +1 位作者 赵金洲 刘慈群 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2005年第5期571-578,共8页
Based on the flow mechanism of hydraulic fractured wells, through integrating linear-flow model and effective well-radius model, a new model of well test analysis for wells with vertical fracture was established. In t... Based on the flow mechanism of hydraulic fractured wells, through integrating linear-flow model and effective well-radius model, a new model of well test analysis for wells with vertical fracture was established. In the model, wellbore storage, the damage in the wall of fracture and all kinds of boundary conditions are considered. The model is concise in form, has intact curves and computes fast, which may meet the demand of real-time computation and fast responded well test interpretation. A new method to determine effective well radius was presented, and the correlation between effective well radius and the fracture length, fracture conductivity, skin factor of fracture was given. Matching flow rate or pressure tested, the optimization model that identified formation and fracture parameters was set up. The automatic matching method was presented by synthetically using step by step linear least square method and sequential quadratic programming. At last, the application was also discussed. Application shows that all of these results can analyze and evaluate the fracturing treatment quality scientifically and rationally, instruct and modify the design of fracturing and improve fracturing design level. 展开更多
关键词 vertical fracture well test fluid flow through porous medium MODEL automatic matching method
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Automation of choice of instrumental equipment and study of thermo-stressed conditions of metal-cutting instrument
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作者 Anatoly V.Levchenko Roman A.Eshenko Olga I.Skarlykina 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2000年第S1期87-87,共1页
This article about possibility of automations of choice of instrumental equipment. In it described problems of choice of equipment, which are decided by means of mathematical model, developed on the base of finite ele... This article about possibility of automations of choice of instrumental equipment. In it described problems of choice of equipment, which are decided by means of mathematical model, developed on the base of finite element method. 展开更多
关键词 automatization INSTRUMENTAL EQUIPMENT mathematical model arrangement INSTRUMENTAL block metal-cutting instrument thermal-stressed condition finite element method
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A Comparison of Weighing Methods Prior to Fusion Preparing Iron Samples for XRF Analysis
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作者 Louis Lefrancois Perreault Mathieu Bouchard 《Journal of Chemistry and Chemical Engineering》 2019年第2期93-100,共8页
Sample preparation by fusion for XRF analysis is all about knowing the exact weights of the sample and the flux (sample-to-flux ratio). The whole analytical chain, including the weighing step in sample preparation pri... Sample preparation by fusion for XRF analysis is all about knowing the exact weights of the sample and the flux (sample-to-flux ratio). The whole analytical chain, including the weighing step in sample preparation prior to fusion, is of crucial importance to get precise and accurate x-ray fluorescence (XRF) results. Consequently, the weighing method will affect the quality of the analytical results given by the spectrometer. In this study, the effects of different weighing methods on the precision (RSD) of the obtained XRF results are compared to determine the best weighing method for sample preparation by fusion in terms of comparable precisions in the XRF results. 展开更多
关键词 WEIGHING method SAMPLE preparation by FUSION tolerance accepted XRF analysis precision accuracy ANALYTICAL method sample-to-flux ratio ANALYTICAL results automatIC dispensing balance automatIC WEIGHING instrument
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