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A New Device for Gas-Liquid Flow Measurements Relying on Forced Annular Flow
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作者 Tiantian Yu Youping Lv +5 位作者 Hao Zhong Ming Liu Pingyuan Gai Zeju Jiang Peng Zhang Xingkai Zhang 《Fluid Dynamics & Materials Processing》 EI 2024年第8期1759-1772,共14页
A new measurement device,consisting of swirling blades and capsule-shaped throttling elements,is proposed in this study to eliminate typical measurement errors caused by complex flow patterns in gas-liquid flow.The sw... A new measurement device,consisting of swirling blades and capsule-shaped throttling elements,is proposed in this study to eliminate typical measurement errors caused by complex flow patterns in gas-liquid flow.The swirling blades are used to transform the complex flow pattern into a forced annular flow.Drawing on the research of existing blockage flow meters and also exploiting the single-phase flow measurement theory,a formula is introduced to measure the phase-separated flow of gas and liquid.The formula requires the pressure ratio,Lockhart-Martinelli number(L-M number),and the gas phase Froude number.The unknown parameters appearing in the formula are fitted through numerical simulation using computational fluid dynamics(CFD),which involves a comprehensive analysis of the flow field inside the device from multiple perspectives,and takes into account the influence of pressure fluctuations.Finally,the measurement model is validated through an experimental error analysis.The results demonstrate that the measurement error can be maintained within±8%for various flow patterns,including stratified flow,bubble flow,and wave flow. 展开更多
关键词 Gas-liquid flow measurement blocking flowmeter measurement model pressure fluctuations numerical simulation experimental control
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Multiple Measurement Models of Articulated Arm Coordinate Measuring Machines 被引量:6
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作者 ZHENG Dateng XIAO Zhongyue XIA Xiang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第5期994-998,共5页
The existing articulated arm coordinate measuring machines(AACMM) with one measurement model are easy to cause low measurement accuracy because the whole sampling space is much bigger than the result in the unstable... The existing articulated arm coordinate measuring machines(AACMM) with one measurement model are easy to cause low measurement accuracy because the whole sampling space is much bigger than the result in the unstable calibration parameters. To compensate for the deficiency of one measurement model, the multiple measurement models are built by the Denavit-Hartenberg's notation, the homemade standard rod components are used as a calibration tool and the Levenberg-Marquardt calibration algorithm is applied to solve the structural parameters in the measurement models. During the tests of multiple measurement models, the sample areas are selected in two situations. It is found that the measurement errors' sigma value(0.083 4 ram) dealt with one measurement model is nearly two times larger than that of the multiple measurement models(0.043 1 ram) in the same sample area. While in the different sample area, the measurement errors' sigma value(0.054 0 ram) dealt with the multiple measurement models is about 40% of one measurement model(0.137 3 mm). The preliminary results suggest that the measurement accuracy of AACMM dealt with multiple measurement models is superior to the accuracy of the existing machine with one measurement model. This paper proposes the multiple measurement models to improve the measurement accuracy of AACMM without increasing any hardware cost. 展开更多
关键词 articulated arm coordinate measuring machine multiple measurement models sample area measurement accuracy
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Unascertained measurement classifying model of goal collapse prediction 被引量:7
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作者 董陇军 彭刚剑 +2 位作者 付玉华 白云飞 刘有芳 《Journal of Coal Science & Engineering(China)》 2008年第2期221-224,共4页
Based on optimized forecast method of unascertained classifying,a unascer- tained measurement classifying model (UMC) to predict mining induced goaf collapse was established,The discriminated factors of the model are ... Based on optimized forecast method of unascertained classifying,a unascer- tained measurement classifying model (UMC) to predict mining induced goaf collapse was established,The discriminated factors of the model are influential factors including over- burden layer type,overburden layer thickness,the complex degree of geologic structure, the inclination angle of coal bed,volume rate of the cavity region,the vertical goaf depth from the surface and space superposition layer of the goaf region.Unascertained mea- surement (UM) function of each factor was calculated.The unascertained measurement to indicate the classification center and the grade of waiting forecast sample was determined by the UM distance between the synthesis index of waiting forecast samples and index of every classification.The training samples were tested by the established model,and the correct rate is 100%.Furthermore,the seven waiting forecast samples were predicted by the UMC model.The results show that the forecast results are fully consistent with the ac- tual situation. 展开更多
关键词 unascertained measurement classifying model GOAF collapse prediction mining engineering
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Soft measurement model of ring's dimensions for vertical hot ring rolling process using neural networks optimized by genetic algorithm 被引量:2
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作者 汪小凯 华林 +3 位作者 汪晓旋 梅雪松 朱乾浩 戴玉同 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第1期17-29,共13页
Vertical hot ring rolling(VHRR) process has the characteristics of nonlinearity,time-variation and being susceptible to disturbance.Furthermore,the ring's growth is quite fast within a short time,and the rolled ri... Vertical hot ring rolling(VHRR) process has the characteristics of nonlinearity,time-variation and being susceptible to disturbance.Furthermore,the ring's growth is quite fast within a short time,and the rolled ring's position is asymmetrical.All of these cause that the ring's dimensions cannot be measured directly.Through analyzing the relationships among the dimensions of ring blanks,the positions of rolls and the ring's inner and outer diameter,the soft measurement model of ring's dimensions is established based on the radial basis function neural network(RBFNN).A mass of data samples are obtained from VHRR finite element(FE) simulations to train and test the soft measurement NN model,and the model's structure parameters are deduced and optimized by genetic algorithm(GA).Finally,the soft measurement system of ring's dimensions is established and validated by the VHRR experiments.The ring's dimensions were measured artificially and calculated by the soft measurement NN model.The results show that the calculation values of GA-RBFNN model are close to the artificial measurement data.In addition,the calculation accuracy of GA-RBFNN model is higher than that of RBFNN model.The research results suggest that the soft measurement NN model has high precision and flexibility.The research can provide practical methods and theoretical guidance for the accurate measurement of VHRR process. 展开更多
关键词 vertical hot ring rolling dimension precision soft measurement model artificial neural network genetic algorithm
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Evaluation of the sustainable development level of countries along the Belt and Road and its impact factors:Empirical analysis based on the Super-efficiency slacks-based measure and Tobit measure models 被引量:1
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作者 Tianhang Huang Xiaoyu Zhao +3 位作者 Chi-Han Ai Shaofeng Chen Yi Wang Xiaoyue Hu 《Chinese Journal of Population,Resources and Environment》 2021年第2期162-170,共9页
Sustainable development is an important component of the Belt and Road Initiative(BRI)and is of great significance for evaluating the levels of sustainable development of countries along this route(henceforth,BRI coun... Sustainable development is an important component of the Belt and Road Initiative(BRI)and is of great significance for evaluating the levels of sustainable development of countries along this route(henceforth,BRI countries).Therefore,this study aims to identify the factors that influence the levels of sustainable development of BRI countries in a reasonable and objective manner.Eventually,this study employs the super efficiency slacks-based measure(Super-SBM)model,which considers unexpected outputs to measure the level of sustainable development of BRI countries.The dynamic change and composition of the sustainable development level of these countries are calculated using the global Malmquist-Luenberger index.Furthermore,the Tobit model is used to identify the factors influencing the level of sustainable development of BRI countries in general and in various categories.The empirical results suggest the following points.(a)The overall level of sustainable development of BRI countries is low,whereas those of high-income and middle-and high-income countries are relatively high.(b)The overall sustainable development levels of BRI countries declined to a certain extent in 2008 owing to the effect of the financial crisis,.However,the sustainable development level of other countries,barring low-income countries,has gradually increased since 2011.(c)Since 2008,technological progress has replaced technical efficiency as the main driving force behind the improvement of the sustainable development level of BRI countries.(d)A U-shaped relationship is observed between the economic and sustainable development levels of these countries.(e)The level of science and technology and the proportion of renewable energy consumption can promote the sustainable development of these countries.Moreover,a negative correlation exists between the level of opening to the outside world and that of sustainable development of countries that mainly export resource-based products and are dominated by labor-intensive export industries.Barring low-income countries,the energy structure plays an effective role in improving the level of sustainable development.Finally,the study presents suggestions for China in the process of coping with the sustainable development of relevant countries during its promotion of the BRI. 展开更多
关键词 Belt and Road Initiative Sustainable development level Super-efficiency slacks-based measure model Global Malmquist-Luenberger Index Tobit model
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The Establishment of Measurement Model and Implementation Strategy for Service Productivity
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作者 Song Yingge Ding Ning Xiao Zhiwen Zhang Yijin 《Chinese Business Review》 2012年第12期1270-1276,共7页
As a key factor of economic growth, productivity has been valued in the academic community. Today, with the rapid development of service industry, the research for service productivity has also attracted wide attentio... As a key factor of economic growth, productivity has been valued in the academic community. Today, with the rapid development of service industry, the research for service productivity has also attracted wide attention. However, in the service industry, because of its own characteristics and properties, measurement of service productivity could not apply for the traditional productivity measurement methods simply. This research first has put out the constitution model of service productivity, and thus put out the measurement model of service productivity. And explains that service productivity is a function which contains internal efficiency, external efficiency, and capacity efficiency. In service productivity, external efficiency is the key one, internal efficie and capacity efficiency should also be given considerations. Eventually, the strategy of implementing measurement of service productivity have been proposed ncy the 展开更多
关键词 SERVICE service productivity constitution model measurement model the difficulty in measurement the strategy of measurement implement
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MEASUREMENT METHOD AND PHYSICAL MODEL OF VSC CONDUCTIVITY AND ITS APPLICATIONS IN CONDUCTING POLYMERS
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作者 万梅香 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1989年第4期330-339,共10页
Method of VSC (Voltage Shorted Compaction)can be used to determine the intrinsic temperature dependence ofconductivity ofpolycrystalline compaction. The experimental conditions and technical key for preparation of VSC... Method of VSC (Voltage Shorted Compaction)can be used to determine the intrinsic temperature dependence ofconductivity ofpolycrystalline compaction. The experimental conditions and technical key for preparation of VSC device and its physical model as well as its applications in conducting polymers are discussed in detail. 展开更多
关键词 VSC show measureMENT METHOD AND PHYSICAL model OF VSC CONDUCTIVITY AND ITS APPLICATIONS IN CONDUCTING POLYMERS
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ZTE Communications Special Issue on Channel Measurement and Modeling for Heterogeneous 5G
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《ZTE Communications》 2016年第B06期50-50,共1页
While cellular networks have continuously evolved in recent years, the industry has clearly seen unprecedented challenges to meet the exponentially growing expectations in the near future.
关键词 ZTE Communications Special Issue on Channel measurement and modeling for Heterogeneous 5G EMAIL
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ZTE Communications Special Issue on Channel Measurement and Modeling for Heterogeneous 5G
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《ZTE Communications》 2016年第3期59-59,共1页
While cellular networks have continuously evolved in re- cent years, the industry has clearly seen unprecedented chal- lenges to meet the exponentially growing expectations in the near future. The 5G system is facing ... While cellular networks have continuously evolved in re- cent years, the industry has clearly seen unprecedented chal- lenges to meet the exponentially growing expectations in the near future. The 5G system is facing grand challenges such as the ever-increasing traffic volumes and remarkably diver- sified services connecting humans and machines alike. As a result, the future network has to deliver massively increased capacity, greater flexibility, incorporated computing capabili- ty, support of significantly extended battery lifetime, and ac- commodation of varying payloads with fast setup and low latency, etc. In particular, as 5G requires more spectrum resource, higher frequency bands are desirable. Nowadays, millimeter wave has been widely accepted as one of the main communication bands for 5G. 展开更多
关键词 ZTE Communications Special Issue on Channel measurement and modeling for Heterogeneous 5G EMAIL
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Spatiotemporal characteristics of cultivated land use eco-efficiency and its influencing factors in China from 2000 to 2020 被引量:1
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作者 LI Shaoting MU Na +1 位作者 REN Yanjun Thomas GLAUBEN 《Journal of Arid Land》 SCIE CSCD 2024年第3期396-414,共19页
Improving cultivated land use eco-efficiency(CLUE)can effectively promote agricultural sustainability,particularly in developing countries where CLUE is generally low.This study used provincial-level data from China t... Improving cultivated land use eco-efficiency(CLUE)can effectively promote agricultural sustainability,particularly in developing countries where CLUE is generally low.This study used provincial-level data from China to evaluate the spatiotemporal evolution of CLUE from 2000 to 2020 and identified the influencing factors of CLUE by using a panel Tobit model.In addition,given the undesirable outputs of agricultural production,we incorporated carbon emissions and nonpoint source pollution into the global benchmark-undesirable output-super efficiency-slacks-based measure(GB-US-SBM)model,which combines global benchmark technology,undesirable output,super efficiency,and slacks-based measure.The results indicated that there was an upward trend in CLUE in China from 2000 to 2020,with an increase rate of 2.62%.The temporal evolution of CLUE in China could be classified into three distinct stages:a period of fluctuating decrease(2000-2007),a phase of gradual increase(2008-2014),and a period of rapid growth(2015-2020).The major grain-producing areas(MPAs)had a lower CLUE than their counterparts,namely,non-major grain-production areas(non-MPAs).The spatial agglomeration effect followed a northeast-southwest strip distribution;and the movement path of barycentre revealed a"P"shape,with Luoyang City,Henan Province,as the centre.In terms of influencing factors of CLUE,investment in science and technology played the most vital role in improving CLUE,while irrigation index had the most negative effect.It should be noted that these two influencing factors had different impacts on MPAs and non-MPAs.Therefore,relevant departments should formulate policies to enhance the level of science and technology,improve irrigation condition,and promote sustainable utilization of cultivated land. 展开更多
关键词 cultivated land use eco-efficiency(CLUE) slacks-based measure(SBM)model barycentre model standard deviation ellipse(SDE) panel Tobit model carbon emissions nonpoint source pollution
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Measurement and Spatio-temporal Distribution of Urbanization Development Quality of Urban Agglomeration in China 被引量:12
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作者 WANG Deli FANG Chuanglin +2 位作者 GAO Boyang HUANG Jinchuan YANG Qingshan 《Chinese Geographical Science》 SCIE CSCD 2011年第6期695-707,共13页
Urbanization development quality(UDQ) of urban agglomeration(UA) is one of the important indexes to evaluate if the UA urbanization speed is reasonable,if the population urbanization process is sound,if the economic u... Urbanization development quality(UDQ) of urban agglomeration(UA) is one of the important indexes to evaluate if the UA urbanization speed is reasonable,if the population urbanization process is sound,if the economic urbanization process is efficient,if the social urbanization process is harmonious and fair,which is generally composed of three parts,including economic urbanization development quality,social urbanization development quality and spa-tial urbanization security quality.With the research of evolution rules of UDQ,through the analysis on the interactive coordination relation between UDQ and urbanization level,the paper proposes three dimensional index ball and stan-dard value of comprehensive measures of UDQ,which is composed of three categories of indexes.By introducing At-kinson model,this paper constructs the sub-element measure model and segmental measure model of UDQ,and fur-ther makes an overall evaluation on the characteristic of UDQ of UAs in China.Results show that:1) UDQ of UAs lied at optimization and upgrading phase during 1995-2008 and the quality was low.Population urbanization level did not reflect the UDQ of UAs;2) the improving speed of the spatial urbanization security quality was higher than the so-cial urbanization development quality,and the improving speed of economic urbanization development quality was the lowest;3) the coordination between UDQ and urbanization level was not so good;4) there was a weak correlation re-lation between UDQ and UA scale,and it was not true that the bigger the UA was,the better the UDQ was. 展开更多
关键词 urbanization development quality (UDQ) urbanization speed comprehensive measure model urban ag-glomeration (UA)
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Integrating unascertained measurement and information entropy theory to assess blastability of rock mass 被引量:15
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作者 周健 李夕兵 《Journal of Central South University》 SCIE EI CAS 2012年第7期1953-1960,共8页
Due to the complex features of rock mass blastability assessment systems, an evaluation model of rock mass blastability was established on the basis of the unascertained measurement (UM) theory and the actual charac... Due to the complex features of rock mass blastability assessment systems, an evaluation model of rock mass blastability was established on the basis of the unascertained measurement (UM) theory and the actual characteristics of the project. Considering a comprehensive range of intact rock properties and discontinuous structures of rock mass, twelve main factors influencing the evaluation blastability of rock mass were taken into account in the UM model, and the blastability evaluation index system of rock mass was constructed. The unascertained evaluation indices corresponding to the selected factors for the actual situation were solved both qualitatively and quantitatively. Then, the UM function of each evaluation index was obtained based on the initial data for the analysis of the blastability of six rock mass at a highway improvement cutting site in North Wales. The index weights of the factors were calculated by entropy theory, and credible degree identification (CDI) criteria were established according to the UM theory. The results of rock mass blastability evaluation were obtained by the CDI criteria. The results show that the UM model assessment results agree well with the actual records, and are consistent with those of the fuzzy sets evaluation method. Meanwhile, the unascertained superiority degree of rock mass blastability of samples S1-$6 which can be calculated by scoring criteria are 3.428 5, 3.453 3, 4.058 7, 3.675 9, 3.516 7 and 3.289 7, respectively. Furthermore, the proposed method can take into account large amount of uncertain information in blastability evaluation, which can provide an effective, credible and feasible way for estimating the blastability of rock mass. Engineering practices show that it can complete the blastability assessment systematically and scientifically without any assumption by the proposed model, which can be applied to practical engineering. 展开更多
关键词 rock mass BLASTABILITY unascertained measurement (UM) model information entropy PREDICTION
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Experimental and modelling study of the solubility of CO_2 in various CaCl_2 solutions at different temperatures and pressures 被引量:3
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作者 Alireza Bastami Mohammad Allahgholi Peyman Pourafshary 《Petroleum Science》 SCIE CAS CSCD 2014年第4期569-577,共9页
Study of the thermodynamic behaviour of CaCl2-H2O-CO2 systems is important in different scientific areas in the chemical and petroleum engineering fields. For example, a system including salt- H20-CO2 is a common syst... Study of the thermodynamic behaviour of CaCl2-H2O-CO2 systems is important in different scientific areas in the chemical and petroleum engineering fields. For example, a system including salt- H20-CO2 is a common system in CO2 geological storage. During carbonate matrix acidizing, this mixture also appears as the spent acid. Hence, study of the behaviour of this system and the solubility of CO2 in CaCl2 brine in different thermodynamic conditions is critical. In this study, CO2 solubility in 0, 1.90 and 4.80 mol/L CaCl2 solutions at 328.15 to 375.15 K and 68.9 to 206.8 bar were measured. These values are normal for oil reservoirs. A popular thermodynamic model is available in the literature for estimating the CO2 solubility in pure water and NaC1 solutions. In this paper, the available model was modified by experimental work to be applicable for CaCl2 as well. Based on the measured data, the component interaction parameters in the base model were adjusted for a CaCl2-H2O-CO2 system. The developed model could predict CO2 solubility in different conditions with remarkable accuracy, particularly for high concentration solutions and at high pressures. This improvement is up to 65% better than in the base model. This model can be used in Darcy scale models for predicting wormhole propagation during carbonate matrix acidizing. 展开更多
关键词 Solubility of CO2-CaCl2 carbonate acidizing spent acid wormhole propagation modelling solubility measurement
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Singularity of Some Software Reliability Models and Parameter Estimation Method 被引量:1
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作者 XU Ren-zuo ZHOU Rui YANG Xiao-qing (State Key Laboratory of Software Engineering, Wuhan University, Wuhan 430072, China) 《Wuhan University Journal of Natural Sciences》 EI CAS 2000年第1期35-40,共6页
According to the principle, “The failure data is the basis of software reliability analysis”, we built a software reliability expert system (SRES) by adopting the artificial intelligence technology. By reasoning out... According to the principle, “The failure data is the basis of software reliability analysis”, we built a software reliability expert system (SRES) by adopting the artificial intelligence technology. By reasoning out the conclusion from the fitting results of failure data of a software project, the SRES can recommend users “the most suitable model” as a software reliability measurement model. We believe that the SRES can overcome the inconsistency in applications of software reliability models well. We report investigation results of singularity and parameter estimation methods of experimental models in SRES. 展开更多
关键词 software reliability measurement models software reliability expert system SINGULARITY parameter estimation method path following method maximum likelihood ML-fitting algorithm
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Study and application of monitoring plane displacement of a similarity model based on time-series images 被引量:5
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作者 Xu Jiankun Wang Enyuan +1 位作者 Li Zhonghui Wang Chao 《Mining Science and Technology》 EI CAS 2011年第4期501-505,共5页
In order to compensate for the deficiency of present methods of monitoring plane displacement in similarity model tests,such as inadequate real-time monitoring and more manual intervention,an effective monitoring meth... In order to compensate for the deficiency of present methods of monitoring plane displacement in similarity model tests,such as inadequate real-time monitoring and more manual intervention,an effective monitoring method was proposed in this study,and the major steps of the monitoring method include:firstly,time-series images of the similarity model in the test were obtained by a camera,and secondly,measuring points marked as artificial targets were automatically tracked and recognized from time-series images.Finally,the real-time plane displacement field was calculated by the fixed magnification between objects and images under the specific conditions.And then the application device of the method was designed and tested.At the same time,a sub-pixel location method and a distortion error model were used to improve the measuring accuracy.The results indicate that this method may record the entire test,especially the detailed non-uniform deformation and sudden deformation.Compared with traditional methods this method has a number of advantages,such as greater measurement accuracy and reliability,less manual intervention,higher automation,strong practical properties,much more measurement information and so on. 展开更多
关键词 Plane displacement monitoring Similarity model test Time-series images Displacement measurement
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A Learning-Based Channel Model for Synergetic Transmission Technology 被引量:4
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作者 Liang Chen Li Haihan +2 位作者 Li Yunzhou Zhou Shidong Wang Jing 《China Communications》 SCIE CSCD 2015年第9期83-92,共10页
It is extensively approved that Channel State Information(CSI) plays an important role for synergetic transmission and interference management. However, pilot overhead to obtain CSI with enough precision is a signific... It is extensively approved that Channel State Information(CSI) plays an important role for synergetic transmission and interference management. However, pilot overhead to obtain CSI with enough precision is a significant issue for wireless communication networks with massive antennas and ultra-dense cell. This paper proposes a learning- based channel model, which can estimate, refine, and manage CSI for a synergetic transmission system. It decomposes the channel impulse response into multiple paths, and uses a learning-based algorithm to estimate paths' parameters without notable degradation caused by sparse pilots. Both indoor measurement and outdoor measurement are conducted to verify the feasibility of the proposed channel model preliminarily. 展开更多
关键词 channel model CSI synergetic transmission spectral efficiency learning-based channel measurement
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A Cost-benefit Measuring Model of Green Products in Manufacturing Industry 被引量:1
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作者 Qingshan Zhang Luping Zhang 《Chinese Business Review》 2005年第5期8-15,共8页
The paper builds up a cost-benefit measuring model of green products in manufacturing industry throughout its full life cycle, which can quantify green products' cost and benefit completely and correctly under the ci... The paper builds up a cost-benefit measuring model of green products in manufacturing industry throughout its full life cycle, which can quantify green products' cost and benefit completely and correctly under the circumstance of satisfying enterprise, customer, environment and society. It also puts forth an operable method to estimate social benefit by opportunity cost and establishes a profit maximization-programming model. The model can be applied to justify whether some kinds of green products should be developed and produced. 展开更多
关键词 green product full life cycle social benefit estimation the measuring model
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Recent Developments of Image Based Measurement Methods for Application to Transonic Flows in Industrial Wind Tunnels
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作者 J.KOMPENHANS J.AGOCS +16 位作者 Y.EGAMI R.ENGLER U.FEY H.FRAHNERT K.de GROOT U.HENNE T.KIRMSE C.KLEIN F.KLINGE R.KONRATH L.KOOP H.MATTNER D.OTTER D.PALLEK W.SACHS A.SCHRDER B.STASICKI 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2006年第2期114-125,共12页
The experimental investigation of unsteady complex flow fields in wind tunnels requires advanced measurement techniques. The most important of such image based measurement techniques are those for the measurement of p... The experimental investigation of unsteady complex flow fields in wind tunnels requires advanced measurement techniques. The most important of such image based measurement techniques are those for the measurement of planar flow velocity fields, planar pressure distribution, model location and deformation, model temperature and quantitative high speed flow visualization. The applications as carried out by DLR range from low speed flows to transonic flows, from high lift configurations to propellers and rotors, from wake vortex investigations in catapult facilities and water towing tanks to investigations of vortex break down phenomena on delta wings. The capability to use image based measurement techniques in transonic flows requires dedicated technical developments and experienced scientists due to the special environment of a transonic wind tunnel. In this paper an overview of the state-of-the art of the application of image based measurement techniques in transonic flows as performed by DLR's Institute of Aerodynamics and Flow Technology will be given. 展开更多
关键词 industrial wind tunnel transonic flow image based measurement techniques pressure sensitive paint particle image velocimetry model deformation measurement techniques THERMOGRAPHY non-standard video techniques
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Singularity of Software Reliability Models LVLM and LVQM
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作者 XU Ren zuo ZHOU Rui YANG Xiao qing 《Wuhan University Journal of Natural Sciences》 EI CAS 2000年第2期150-154,共5页
According to the principle, “The failure data is the basis of software reliabilityanalysis”, we built a software reliability expert system (SRES) by adopting the artificialtechnology. By reasoning out the conclusion... According to the principle, “The failure data is the basis of software reliabilityanalysis”, we built a software reliability expert system (SRES) by adopting the artificialtechnology. By reasoning out the conclusion from the fitting results of failure data of asoftware project, the SRES can recommend users “the most suitable model” as a softwarereliability measurement model. We believe that the SRES can overcome the inconsistency inapplications of software reliability models well. We report investigation results of singularity and parameter estimation methods of models, LVLM and LVQM. 展开更多
关键词 software reliability measurement models software reliability expert system SINGULARITY parameter estimation method LVLM LVQM
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Modeling Multisource-heterogeneous Information Based on Random Set and Fuzzy Set Theory
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作者 文成林 徐晓滨 《Journal of Donghua University(English Edition)》 EI CAS 2006年第6期87-92,共6页
This paper presents a new idea, named as modeling multisensor-heterogeneous information, to incorporate the fuzzy logic methodologies with mulitsensor-multitarget system under the framework of random set theory. First... This paper presents a new idea, named as modeling multisensor-heterogeneous information, to incorporate the fuzzy logic methodologies with mulitsensor-multitarget system under the framework of random set theory. Firstly, based on strong random set and weak random set, the unified form to describe both data (unambiguous information) and fuzzy evidence (uncertain information) is introduced. Secondly, according to signatures of fuzzy evidence, two Bayesian-markov nonlinear measurement models are proposed to fuse effectively data and fuzzy evidence. Thirdly, by use of "the models-based signature-matching scheme", the operation of the statistics of fuzzy evidence defined as random set can be translated into that of the membership functions of relative point state variables. These works are the basis to construct qualitative measurement models and to fuse data and fuzzy evidence. 展开更多
关键词 random set theory DATA fuzzy evidence fuzzy membership functions qualitative measurement model.
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