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产出资源配置效率的参数测度与非参数测度及其比较分析 被引量:11
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作者 孙巍 杨庆芳 杨树绘 《系统工程理论与实践》 EI CSCD 北大核心 2000年第6期118-122,共5页
投入压缩和产出扩张是生产资源配置效率改进的两个基本途径 .本文基于前沿生产函数理论研究了产出资源配置效率的 C- D生产函数参数测度模型与非参数测度模型 ,根据微观经济学理论研究了产出效率分解 ,并通过实证测算分析验证了产出资... 投入压缩和产出扩张是生产资源配置效率改进的两个基本途径 .本文基于前沿生产函数理论研究了产出资源配置效率的 C- D生产函数参数测度模型与非参数测度模型 ,根据微观经济学理论研究了产出效率分解 ,并通过实证测算分析验证了产出资源配置效率理论与方法的正确性和实用性 。 展开更多
关键词 汽车行业 产业资源配置效率 参数测度
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电力工业的非参数效率测度分析 被引量:3
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作者 王金祥 吴育华 +1 位作者 刘喜华 孙巍 《北京科技大学学报》 EI CAS CSCD 北大核心 2002年第4期466-470,共5页
对资源优化配置的非参数模型在电力工业中的应用进行了研究.选择了国内部分电网的数据,从纯技术效率、规模效率以及投入可处置度、投入组合效率、投入综合效率的角度对部分电力企业的资源配置效率进行了横向分析,结果表明,不同的电力企... 对资源优化配置的非参数模型在电力工业中的应用进行了研究.选择了国内部分电网的数据,从纯技术效率、规模效率以及投入可处置度、投入组合效率、投入综合效率的角度对部分电力企业的资源配置效率进行了横向分析,结果表明,不同的电力企业之间的资源配置效率差距较大,电力企业总体上生产性投资的要素组合比例不合理,利用率较低. 展开更多
关键词 参数效率测度 参数模型 效率分解 电力工业 资源配置 技术效率测度 投入效率
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基于界面测度参数的传统街道空间优化策略研究--以青岛市中山路为例 被引量:2
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作者 赵琳 李芙蓉 +1 位作者 吴廷金 仲筱 《华中建筑》 2020年第10期28-32,共5页
界面是街道空间中的重要组成部分,其特征直接影响人对街道空间的感受和街道活力。在已有的街道研究中,界面通常被作为组成要素而导致其对街道空间的影响力被忽视。该文以青岛传统商业街道中山路为例,运用贴线率、面宽比、店面密度三个... 界面是街道空间中的重要组成部分,其特征直接影响人对街道空间的感受和街道活力。在已有的街道研究中,界面通常被作为组成要素而导致其对街道空间的影响力被忽视。该文以青岛传统商业街道中山路为例,运用贴线率、面宽比、店面密度三个参数量化分析界面外观特征和内在功能活力。研究发现,相关界面参数的应用能准确识别街道中严重不协调的街段;路口数量过多对贴线率和界面连续性有消极影响;同质化竞争激烈是闲置店面增多的重要原因。最后,对此提出相关优化策略。 展开更多
关键词 街道界面 测度参数 中山路 优化策略
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基于小波分形维的端锚锚杆的动测度参数研究
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作者 陈海成 孟祥程 《价值工程》 2015年第1期128-129,共2页
本文通过不同张拉荷载等级下两种工况的室内实验研究,采用小波以及分形维思想,再通过整周期逼近信号的衰减计算,得到了能够定量评价锚固质量优劣的三个动测度参数。
关键词 锚杆 无损检测 应力波 小波分形维 测度参数 Matlab
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关于参数化测度(Ⅲ)
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作者 陈泽乾 《荆州师专学报》 1996年第5期3-8,共6页
建立无限状态空间上的Riesz表示定理和Radon-Nikodym定理
关键词 ω*-积分 测度 扩张 超过程 偏Radon-Nikodym导数 参数测度
全文增补中
关于参数化测度(I)
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作者 陈泽乾 《荆州师专学报》 1995年第5期1-4,共4页
本文得到了参数化的RadonNikodym定理和参数化的Riesz表示定理,并证明了它们与经典的结果等价。
关键词 参数测度 偏μ-连续 测度的偏导
全文增补中
关于参数化测度(Ⅱ)
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作者 陈泽乾 《荆州师专学报》 1996年第2期1-6,共6页
引进一类拓扑向量空间,用以描述测度的偏导。使用的工具是所谓的参数化鞅。建立了若干参数化鞅的收敛定理。
关键词 参数测度 测度的偏导 参数化鞅 局部凸拓扑向量空间
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Effect of gas saturation on P-wave velocity in tight sandstone
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作者 Pan Bao-Zhi Zhou Wei-Yi +2 位作者 Guo Yu-Hang Fang Chun-Hui Zhang Li-Hua 《Applied Geophysics》 SCIE CSCD 2024年第3期487-495,617,共10页
By measuring the variation of the P-and S-wave velocities of tight sandstone samples under water saturation,it was confirmed that with the decrease in water saturation,the P-wave velocity first decreased and then incr... By measuring the variation of the P-and S-wave velocities of tight sandstone samples under water saturation,it was confirmed that with the decrease in water saturation,the P-wave velocity first decreased and then increased.The variation in velocity was influenced by the sandstone’s porosity.The commonly used Gassmann equation based on fluid substitution theory was studied.Comparing the calculated results with the measured data,it was found that the Gassmann equation agreed well with the measured data at high water saturation,but it could not explain the bending phenomenon of P-wave velocity at low saturation.This indicated that these equations could not accurately describe the relationship between fluid content and rock acoustic velocity.The reasons for this phenomenon were discussed through Taylor’s expansion.The coefficients of the fitting formula were calculated and verified by fitting the measured acoustic velocity changes of the cores.The relationship between P-wave velocity and saturation was discussed,which provides experimental support for calculating saturation using seismic and acoustic logging data. 展开更多
关键词 Tight sandstone Saturation model Reservoir parameters Acoustic wave measurement
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基于支持向量机的景象匹配区选择方法 被引量:11
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作者 杨朝辉 陈映鹰 《同济大学学报(自然科学版)》 EI CAS CSCD 北大核心 2009年第5期690-695,共6页
考虑景象匹配区选择结果与参考图像信息之间的联系与制约,提出了基于支持向量机的景象匹配区选择方法.首先合理选择基于灰度和基于特征的2级测度参数,准确有效地表示参考图图像信息;其次将多个测度参数归一化组成样本集的输入属性向量,... 考虑景象匹配区选择结果与参考图像信息之间的联系与制约,提出了基于支持向量机的景象匹配区选择方法.首先合理选择基于灰度和基于特征的2级测度参数,准确有效地表示参考图图像信息;其次将多个测度参数归一化组成样本集的输入属性向量,并使用去均值归一化算法得到匹配结果作为样本集的输出;最后选择合适的核函数与最佳参数训练样本集数据,得到具有自动区分景象适配区与非景象匹配区能力的决策函数,并用其分类实现任意候选参考图的匹配区选择.实验结果表明该方法具有较大的适应性和抗干扰性,能够对复杂参考图的匹配区选择进行正确决策指导. 展开更多
关键词 景象匹配 支持向量机 测度参数 匹配区
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A quantitative analysis on the sources of dune sand in the Hulun Buir Sandy Land:application of stepwise discriminant analysis (SDA) to the granulometric data 被引量:1
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作者 HANGuang ZHANGGuifang YANGWenbin 《Journal of Geographical Sciences》 SCIE CSCD 2004年第2期177-186,共10页
Quantitatively determining the sources of dune sand is one of the problems necessarily and urgently to be solved in aeolian landforms and desertification research. Based on the granulometric data of sand materials fro... Quantitatively determining the sources of dune sand is one of the problems necessarily and urgently to be solved in aeolian landforms and desertification research. Based on the granulometric data of sand materials from the Hulun Buir Sandy Land, the paper employs the stepwise discriminant analysis technique (SDA) for two groups to select the principal factors determining the differences between surface loose sediments. The extent of similarity between two statistical populations can be described quantitatively by three factors such as the number of principal variables, Mahalanobis distance D 2 and confidence level 琢for F-test. Results reveal that: 1) Aeolian dune sand in the region mainly derives from Hailar Formation (Q 3 ), while fluvial sand and palaeosol also supply partially source sand for dunes; and 2) in the vicinity of Cuogang Town and west of the broad valley of the lower reaches of Hailar River, fluvial sand can naturally become principal supplier for dune sand. 展开更多
关键词 Hulun Buir Sandy Land granulometric analysis stepwise discriminant analysis dune sand Hailar Formation fluvial sandy sediments
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Optical Fiber Instrument for Single-point Multi-parameter Measurement 被引量:1
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作者 WANGYu-tian WANGXiao-dong 《Semiconductor Photonics and Technology》 CAS 2001年第4期221-224,共4页
A novel kind of optical fiber instrument for two channel measurement of temperature and displacement was developed. Four channel quartz fiber optics were employed to measure two channel signals of temperature and disp... A novel kind of optical fiber instrument for two channel measurement of temperature and displacement was developed. Four channel quartz fiber optics were employed to measure two channel signals of temperature and displacement simultaneously, and the operating efficiency of this instrument was greatly improved. 展开更多
关键词 Fiber optics TEMPERATURE DISPLACEMENT
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Selection of Measured Signals in the Navigation Measuring Complex 被引量:1
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作者 柯芳 Andrey PROLETARSKY Konstantin NEUSIPIN 《Journal of Measurement Science and Instrumentation》 CAS 2011年第4期346-348,共3页
To increase accuracy of navigation parameters,a perspective measuring complex with intellectual components is developed.Conception of synthesis optimal structure of the measuring complex is realized basing on a select... To increase accuracy of navigation parameters,a perspective measuring complex with intellectual components is developed.Conception of synthesis optimal structure of the measuring complex is realized basing on a selective method using principles of the functional systems.Selection of measured information is finished by original numeric criterion of observation level of state vector components.Prediction is realized by algorithm of self-organization that makes synthesis of the optimal complication.Therefore mechanism of self-regulation is realized and accuracy of the selective navigation complex is increased. 展开更多
关键词 selected navigation complex functional systems intellectual components observation level selforganiza tion
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Soft measurement for component content based on adaptive model of Pr/Nd color features 被引量:5
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作者 陆荣秀 杨辉 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第12期1981-1986,共6页
For measurement of component content in the extraction and separation process of praseodymium/neodymium(Pr/Nd), a soft measurement method was proposed based on modeling of ion color features, which is suitable for fas... For measurement of component content in the extraction and separation process of praseodymium/neodymium(Pr/Nd), a soft measurement method was proposed based on modeling of ion color features, which is suitable for fast estimation of component content in production field. Feature analysis on images of the solution is conducted,which are captured from Pr/Nd extraction/separation field. H/S components in the HSI color space are selected as model inputs, so as to establish the least squares support vector machine(LSSVM) model for Nd(Pr) content,while the model parameters are determined with the GA algorithm. To improve the adaptability of the model,the adaptive iteration algorithm is used to correct parameters of the LSSVM model, on the basis of model correction strategy and new sample data. Using the field data collected from rare earth extraction production, predictive methods for component content and comparisons are given. The results indicate that the proposed method presents good adaptability and high prediction precision, so it is applicable to the fast detection of element content in the rare earth extraction. 展开更多
关键词 Pr/Nd extraction Color feature Component content Adaptive iterative least squares support vector machine Real-time correction
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ECT Image Analysis Methods for Shear Zone Measurements during Silo Discharging Process 被引量:1
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作者 Krzysztof Grudzien Zbigniew Chaniecki +2 位作者 Andrzej Romanowski Maciej Niedostatkiewicz Dominik Sankowski 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第2期337-345,共9页
The paper covers the electrical capacitance tomography(ECT) data analysis on shear zones formed during silo discharging process.This is due to the ECT aptitude for detection of slight changes of material concentration... The paper covers the electrical capacitance tomography(ECT) data analysis on shear zones formed during silo discharging process.This is due to the ECT aptitude for detection of slight changes of material concentration.On the basis of ECT visualisations,wall-adjacent shear zone profiles are analysed for different wall roughness parameters.The analysis on changes of material concentration,based on ECT images,enables the calculation for the characteristic parameters of shear zones-size and material concentration inside the shear zone in a dynamic process of silo discharging.In order to verify the methodology a series of experiments on gravitational flow of bulk solids under various conditions were conducted with different initial granular material packing densities and silo wall roughness.The investigation shows that the increase in container wall roughness is an effective method for reducing the dynamic effects during the material discharging,since these effects are resulted from the resonance between hopper construction and trembling material.Such effects will damage industrial equipment in practical applications and need further investigation. 展开更多
关键词 electrical capacitance tomography silo flow shear zone
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Virtual test system for permanent-magnet DC motor 被引量:1
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作者 崔淑梅 王悦 +3 位作者 柴凤 吴红星 刘宝廷 程树康 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2003年第2期200-204,共5页
In order to obtain the primary parameters and operating characteristics of a DC motor without directly measuring its torque and rational speed, it is proposed to use a PC and a data acquisition card to acquire both th... In order to obtain the primary parameters and operating characteristics of a DC motor without directly measuring its torque and rational speed, it is proposed to use a PC and a data acquisition card to acquire both the dynamic and static data of armature current to establish the performance of a DC permanent magnet motor. The accuracy and validity of this virtual test system proposed were verified by comparing the measurements made with the system proposed with the measurements made with conventional torque meters. It is concluded from the results of comparison that from the mathematic model established for the DC permant magnet motors, both major parameters and operating characteristics can be directly established for the DC motors without measuring their torques and rotational speed, a perfect on line measurement and test system has been established for the DC permanent magnet motors using the theory of virtual test system. The system proposed features shorter test time, higher efficiency and lower cost. 展开更多
关键词 virtual system MOTOR test parameter identify
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Sensitivity analysis for parameters of a monitoring system for steep slopes of open-pit mines 被引量:3
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作者 HAN Xue HE Man-chao ZHANG Bi 《Mining Science and Technology》 EI CAS 2009年第4期441-445,共5页
Monitoring the stability of steep slopes of open-pit mines is a major issue relating to production safety in mines.In order to determine the technical parameters of a new type of supervising system applied in monitori... Monitoring the stability of steep slopes of open-pit mines is a major issue relating to production safety in mines.In order to determine the technical parameters of a new type of supervising system applied in monitoring steep slopes of open-pit mines,the MSARMA method was used to establish analytical models for the monitoring system,given various parameter settings based on the description of mechanical monitoring principles.We used this sensitivity analysis to conclude that the setting of the most sensitive location of a mechanical monitoring system should be within a range of 1/5~1/2 of the lower part in a vertical direction of steep slopes,with a rational and feasible range of the dip angle setting between 0°~20°.Given the analytical results of our on-site experiments,we have shown that the parameters determined reflect the stability of steep slopes accurately and effectively.These conclusions provide a basis for the application of a new type of steep slope stability monitoring technology in open-pit mines. 展开更多
关键词 open-pit mine steep slope monitoring system setting parameter analysis
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Application of artificial neural networks and multivariate statistics to estimate UCS using textural characteristics 被引量:14
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作者 Amin Manouchehrian Mostafa Sharifzadeh Rasoul Hamidzadeh Moghadam 《International Journal of Mining Science and Technology》 SCIE EI 2012年第2期229-236,共8页
Before any rock engineering project,mechanical parameters of rocks such as uniaxial compressive strength and young modulus of intact rock get measured using laboratory or in-situ tests,but in some situations preparing... Before any rock engineering project,mechanical parameters of rocks such as uniaxial compressive strength and young modulus of intact rock get measured using laboratory or in-situ tests,but in some situations preparing the required specimens is impossible.By this time,several models have been established to evaluate UCS and E from rock substantial properties.Artificial neural networks are powerful tools which are employed to establish predictive models and results have shown the priority of this technique compared to classic statistical techniques.In this paper,ANN and multivariate statistical models considering rock textural characteristics have been established to estimate UCS of rock and to validate the responses of the established models,they were compared with laboratory results.For this purpose a data set for 44 samples of sandstone was prepared and for each sample some textural characteristics such as void,mineral content and grain size as well as UCS were determined.To select the best predictors as inputs of the UCS models,this data set was subjected to statistical analyses comprising basic descriptive statistics,bivariate correlation,curve fitting and principal component analyses.Results of such analyses have shown that void,ferroan calcitic cement,argillaceous cement and mica percentage have the most effect on USC.Two predictive models for UCS were developed using these variables by ANN and linear multivariate regression.Results have shown that by using simple textural characteristics such as mineral content,cement type and void,strength of studied sandstone can be estimated with acceptable accuracy.ANN and multivariate statistical UCS models,revealed responses with 0.87 and 0.76 regressions,respectively which proves higher potential of ANN model for predicting UCS compared to classic statistical models. 展开更多
关键词 Textural characteristicsUniaxial compressive strengthPredictive modelsArtificial neural networksMultivariate statistics
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Determination Method for Shear Strength Parameters of Rock-Soil Mixtures Using Close-Range Photogrammetry and 3-D Limit Equilibrium Theory 被引量:3
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作者 ZHOU Jia-wen YANG Xing-guo YANG Zhao-hui 《Journal of Mountain Science》 SCIE CSCD 2015年第5期1068-1083,共16页
Using a combination of close-range photogrammetry and three-dimensional(3-D) limit equilibrium theory, a determination method for the shear strength parameters of rock-soil mixture is presented. A close-range photogra... Using a combination of close-range photogrammetry and three-dimensional(3-D) limit equilibrium theory, a determination method for the shear strength parameters of rock-soil mixture is presented. A close-range photogrammetry method is used for measurement of the 3-D terrain of the experimental target. Auto CAD Lisp and EXCEL VBA are used to perform 3-D limit equilibrium analysis of the stability of sliding mass and perform backanalysis of shear strength parameters. The presented method was used to determine the shear strength parameters of rock-soil mixtures at the Liyuan Hydropower Station. The 3-D terrain of sliding surface could be measured notably well using of closerange photogrammetry. The computed results reveal that the cohesion and friction angle of rock-soil mixtures were 3.15 k Pa and 29.88o for test A, respectively, and 4.43 k Pa and 28.30o for test B, respectively, within the range of shear strength parameters, as determined by field and laboratory tests. The computation of shear strength parameters is influenced by the mesh grid number, especially the cohesion of the rock-soil mixture. The application of close-range photogrammetry can reduce the siteworks and improve the computational efficiency and accuracy. 展开更多
关键词 Rock-soil mixtures In-situ horizontalpush-shear test PHOTOGRAMMETRY Limit equilibrium Shear strength parameters
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Characteristics of ventilation coefficient and its impact on urban air pollution 被引量:1
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作者 路婵 邓启红 +2 位作者 刘蔚巍 黄柏良 石灵芝 《Journal of Central South University》 SCIE EI CAS 2012年第3期615-622,共8页
The temporal variation of ventilation coefficient was estimated and a simple model for the prediction of urban ventilation coefficient in Changsha was developed. Firstly, Pearson correlation analysis was used to inves... The temporal variation of ventilation coefficient was estimated and a simple model for the prediction of urban ventilation coefficient in Changsha was developed. Firstly, Pearson correlation analysis was used to investigate the relationship between meteorological parameters and mixing layer height during 2005-2009 in Changsha, China. Secondly, the multi-linear regression model between daytime and nighttime was adopted to predict the temporal ventilation coefficient. Thirdly, the validation of the model between the predicted and observed ventilation coefficient in 2010 was conducted. The results showed that ventilation coefficient significantly varied and remained high during daytime, while it stayed relatively constant and low during nighttime. In addition, the diurnal ventilation coefficient was distinctly negatively correlated with PM10 (particle with the diameter less than 10 μm) concentration in Changsha, China. The predicted ventilation coefficient agreed well with the observed values based on the multi-linear regression models during daytime and nighttime. The urban temporal ventilation coefficient could be accurately predicted by some simple meteorological parameters during daytime and nighttime. The ventilation coefficient played an important role in the PM10 concentration level. 展开更多
关键词 ventilation coefficient mixing layer height particulate matter multi-linear regression
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Enhanced Nucleate Pool-Boiling from a Glass-Peened Calandria Tube
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作者 Randy W.L. Fong Penny D. Neal Chris R. Fraser Chris C. Bramburger Thambiayah Nitheanandan 《Journal of Energy and Power Engineering》 2013年第3期472-479,共8页
Roughening the surfaces of zirconium alloy tubes by glass-bead peening has been shown to increase the CHF (critical heat flux) in pool-boiling of water. The increase in CHF attributed to surface roughening effect ha... Roughening the surfaces of zirconium alloy tubes by glass-bead peening has been shown to increase the CHF (critical heat flux) in pool-boiling of water. The increase in CHF attributed to surface roughening effect has been measured in pool-boiling experiments using small-diameter zirconium alloy tubes that have been glass-peened with different bead sizes, intensity and coverage. The CHF was found to correlate with the fractal roughness measured on the metal surfaces. In this study, the nucleate pool-boiling characteristics of a large diameter Zircaloy-2 CANDU~ calandria tube (outer diameter -132 mm) with a glass-peened outside surface were tested in a pool of water near saturation. The primary objective was to measure the wall temperature and heat flux in order to develop a representative nucleate pool-boiling curve for large-diameter tubes with a glass-peened outside surface. By comparing the experimental results with models (e.g., Rohsenow correlation), a modified boiling correlation has been developed for a glass-peened surface of calandria tubes that includes a surface roughness parameter. 展开更多
关键词 CANDU calandria tube glass-peen surface roughness pool-boiling.
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