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Quality Evaluation of Cardamine macrophylla Willd as an Edible and Medicinal Herb of Tibetan and Qiang Ethnic Groups
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作者 Bochao LI Xiaoxia CAI +2 位作者 Yuebu HAILAI Yifan TIAN Yuan LIU 《Medicinal Plant》 2024年第3期30-34,共5页
[Objectives]To evaluate the quality of Cardamine macrophylla Willd as Tibetan and Qiang medicinal materials,so as to improve its quality standard and evaluate the quality of C.macrophylla Willd in western Sichuan Prov... [Objectives]To evaluate the quality of Cardamine macrophylla Willd as Tibetan and Qiang medicinal materials,so as to improve its quality standard and evaluate the quality of C.macrophylla Willd in western Sichuan Province.[Methods]C.macrophylla Willd produced from western Sichuan Province was used as the sample,and the contents of moisture,total ash,acid-insoluble ash,extract,total flavonoids and quercetin in the ground part of C.macrophylla Willd were determined in accordance with the methods of Chinese Pharmacopoeia(2020 edition).With the above seven indicators as evaluation indicators,the quality of medicinal materials was comprehensively evaluated by cluster analysis and principal component analysis(PCA).[Results]According to the results of each indicator,the moisture content of C.macrophylla Willd sample should not exceed 11.00%,the total ash content should not exceed 18%,the acid-insoluble ash content should not exceed 6%,the extract content should not be less than 19%,the total flavone content(calculated by quercetin)should not be less than 2%,and the quercetin content should not be less than 0.15%.[Conclusions]The sample S7 has the best quality and S6 has the worst quality.In this study,the quantitative analysis method of total flavonoids(quercetin)and quercetin in C.macrophylla Willd was established,and the limits of each indicator were preliminarily formulated. 展开更多
关键词 CARDAMINE macrophylla Willd quality standard Total FLAVONOIDS MULTIVARIATE statistical analysis
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Study on Quality and Safety Trust Early Warning of Dairy Products Based on Statistical Process Control
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作者 Xiao FAN 《Asian Agricultural Research》 2017年第10期63-67,71,共6页
In order to solve such problems as lack of dynamic evaluation system in evaluation of quality and safety trust of dairy products,and weak awareness of prevention,it is necessary to introduce the statistical process co... In order to solve such problems as lack of dynamic evaluation system in evaluation of quality and safety trust of dairy products,and weak awareness of prevention,it is necessary to introduce the statistical process control into the quality and safety trust evaluation system of dairy products,and establish quality and safety trust early warning model for dairy products,so as to determine the control limit of control chart and carry out early warning according to eight criteria. According to the empirical results,the statistical process control is helpful for finding the hidden process risks and providing the necessary basis for enterprises taking positive measures to raise the confidence of consumers. 展开更多
关键词 statistical process control Dairy products quality and safety trust Early warning
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Application of Statistical Process Control for Setting Action Thresholds as Quality Assurance of Dose Verifications in External Beam Radiotherapy
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作者 Philip Kioko Ndonye Samuel Nii Adu Tagoe 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2022年第1期22-35,共14页
Purpose: To test the concept of Statistical Process Control (SPC) as a Quality Assurance (QA) procedure for dose verifications in external beam radiation therapy in conventional and 3D Conformal Radiotherapy (3D-CRT) ... Purpose: To test the concept of Statistical Process Control (SPC) as a Quality Assurance (QA) procedure for dose verifications in external beam radiation therapy in conventional and 3D Conformal Radiotherapy (3D-CRT) treatment of cervical cancer. Materials and Methods: A study of QA verification of target doses of 198 cervical cancer patients undergoing External Beam Radiotherapy (EBRT) treatments at two different cancer treatment centers in Kenya was conducted. The target doses were determined from measured entrance doses by the diode in vivo dosimetry. Process Behavior Charts (PBC) developed by SPC were applied for setting Action Thresholds (AT) on the target doses. The AT set was then proposed as QA limits for acceptance or rejection of verified target doses overtime of the EBRT process. Result and Discussion: Target doses for the 198 patients were calculated and SPC applied to test whether the action limits set by the Process Behavior Charts could be applied as QA for verified doses in EBRT. Results for the two sub-groups of n = 3 and n = 4 that were tested produced action thresholds which are within clinical dose specifications for both conventional AP/PA and 3D-CRT EBRT treatment techniques for cervical cancer. Conclusion: Action thresholds set by SPC were within the clinical dose specification of ±5% uncertainty for both conventional AP/PA and 3D-CRT EBRT treatment techniques for cervical cancer. So the concept of SPC could be applied in setting QA action limits for dose verifications in EBRT. 展开更多
关键词 quality Assurance statistical Process control Action Thresholds Dose Verification External Beam Radiation Therapy
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Assessing the Awareness and Usage of Quality Control Tools with Emphasis to Statistical Process Control (SPC) in Ethiopian Manufacturing Industries
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作者 Leakemariam Berhe Tesfay Gidey 《Intelligent Information Management》 2016年第6期143-169,共27页
Introduction: The present work was devoted to assess the awareness and usage of quality control tools with the emphasis on statistical process control in Ethiopian manufacturing industries. Semi structured questionnai... Introduction: The present work was devoted to assess the awareness and usage of quality control tools with the emphasis on statistical process control in Ethiopian manufacturing industries. Semi structured questionnaire has been employed to executive and technical managers of manufacturing industries of various size and specialism across the country. Stratified random sample method by region was used to select sample industries for the study. The samples used for this study are industries mainly from Oromiya, Addis Ababa, Tigray, Amara, SNNP and Diredawa regions proportional to their size of the available industries. Methods: Exploratory method and descriptive statistics was used for data analysis. Available documents and reports related to quality control policy of the selected companies were investigated. Results and Discussions: The number of manufacturing industries involved in this study was 44. Of the sampled manufacturing industries about 60% are from Oromiya and Addis Ababa regions. It has been reported that 100% of the respondents said that the importance of quality control tools is very important to their organizations’ productivity and quality improvement (Figure 3). Quality control professionals were also asked the extent to which quality control system is working in their industry and majority of the respondents (45%) have indicated that quality control system is working to some extent in their respective industries (Figure 18). Conclusions and Recommendations: Most of the quality department of the industries did not fully recognize the importance of statistical process control as quality control tools. This is mainly due to lack of awareness and motivation of the top managements, shortage of man power in the area, and others together would make it difficult to apply quality control tools in their organization. In general, the industries in Ethiopia are deficient in vigor and found to be stagnant hence less exposed to a highly competitive market and don’t adopt the latest quality control techniques in order to gain knowledge about systems to improve quality and operational performance. We conclude that quality management system has to be established as an independent entity with a real power and hence the quality control department which is responsible for quality can make an irreversible decision with respect to quality of any given product. Moreover, the concerned bodies (government and ministry of industries) should give attention and work together with universities to ensure how these statistical process control techniques could be incorporated in a curriculum of the universities at higher levels in degree and masters programs. Furthermore, different trainings which could improve quality and efficiency of their respective management system should be given as short and long term to the employees including top and middle managers found in various industries relevant to their process. 展开更多
关键词 quality Products AWARENESS USAGE statistical Process control Ethiopia
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基于Statistical Process Control风险等级判定及神经网络模型构建珠海市传染病指数
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作者 周伴群 戴晓捷 +2 位作者 尹锡玲 李德云 肖峻峰 《中国当代医药》 CAS 2022年第5期143-147,F0004,共6页
目的建立珠海市传染病指数预报模型,为传染病风险预测预报提供思路。方法利用统计过程控制(SPC)的控制下限、中线和控制上限划分全市2014—2017年以周次为时间计量单位的流感样病例比例、手足口病及其他感染性腹泻发病率的风险等级(布... 目的建立珠海市传染病指数预报模型,为传染病风险预测预报提供思路。方法利用统计过程控制(SPC)的控制下限、中线和控制上限划分全市2014—2017年以周次为时间计量单位的流感样病例比例、手足口病及其他感染性腹泻发病率的风险等级(布雷图指数采用5、10、20判定)。运用长短时记忆神经网络模型(LSTM)和自回归移动平均模型(ARIMA)对2018年15~19周数据进行预测。计算传染病指数并将预测值与实际值对比进而评估预测一致性。结果珠海市手足口病发病率LSTM模型中,测试集MSE为9.0441,RMSE为3.0073,训练集MSE为1.1812,RMSE为1.0868。其余模型在训练集和测试集均表现良好,没有出现过拟合现象。风险指数等级预测与实际值对比,预测一致率为96.0%。结论利用SPC划分风险等级,运用LSTM等构建传染病指数预测模型可行。 展开更多
关键词 传染病指数 统计过程控制 长短时记忆神经网络模型
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Off-Line Quality Control in Bioproducts Processing: A Case Study in Greece
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作者 Ioannis S. Triantafyllou 《Open Journal of Statistics》 2016年第2期229-238,共10页
In the present article we study the production of grape molasses. Data drawn from a specified biolaboratory, are properly analyzed in order to detect factors that affect significantly the Brix value and the volatile a... In the present article we study the production of grape molasses. Data drawn from a specified biolaboratory, are properly analyzed in order to detect factors that affect significantly the Brix value and the volatile acidity of the final product. The ground that is used for planting and a variety of grapes have been taken into account. Off-line statistical quality control techniques have been employed and the outcomes are displayed and discussed in detail. 展开更多
关键词 Grape Molasses Bioproduct statistical quality control Analysis of Variance
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Memory-Type Control Charts Through the Lens of Cost Parameters
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作者 Sakthiseswari Ganasan You Huay Woon +1 位作者 Zainol Mustafa Dadasaheb G.Godase 《Intelligent Automation & Soft Computing》 SCIE 2023年第4期1-10,共10页
A memory-type control chart utilizes previous information for chart construction.An example of a memory-type chart is an exponentially-weighted moving average(EWMA)control chart.The EWMA control chart is well-known an... A memory-type control chart utilizes previous information for chart construction.An example of a memory-type chart is an exponentially-weighted moving average(EWMA)control chart.The EWMA control chart is well-known and widely employed by practitioners for monitoring small and moderate process mean shifts.Meanwhile,the EWMA median chart is robust against outliers.In light of this,the economic model of the EWMA and EWMA median control charts are commonly considered.This study aims to investigate the effect of cost parameters on the out-of-control average run lengthðARL_(1)Þin implementing EWMA and EWMA median control charts.The economic model was used to compute the ARL_(1) parameter.The 14 input parameters were identified and the analysis was carried out based on the one-parameter-at-a-time basis.When the input parameters change based on a predetermined percentage,the ARL_(1) is affected.According to the results of the EWMA chart,nine input parameters had an effect andfive input parameters had no effect on the ARL_(1) parameter.Further,only seven of the 14 input parameters had an effect on the ARL_(1) of the EWMA median chart.However,the effect of each input parameter on the ARL_(1) was different.Moreover,the ARL_(1) for the EWMA median chart was smaller than the EWMA chart.This analysis is crucial to observe and determine the input parameters that have a significant impact on the ARL_(1) of the EMWA and EWMA median control charts.Hence,practitioners can obtain an overview of the influence of the input parameters on the ARL_(1) when implementing the EWMA and EWMA median control charts. 展开更多
关键词 Economic model average run length memory-type control chart cost parameters statistical quality control
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Simulation on a Car Interior Aerodynamic Noise Control Based on Statistical Energy Analysis 被引量:5
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作者 CHEN Xin WANG Dengfeng MA Zhengdong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第5期1016-1021,共6页
How to simulate interior aerodynamic noise accurately is an important question of a car interior noise reduction. The unsteady aerodynamic pressure on body surfaces is proved to be the key effect factor of car interio... How to simulate interior aerodynamic noise accurately is an important question of a car interior noise reduction. The unsteady aerodynamic pressure on body surfaces is proved to be the key effect factor of car interior aerodynamic noise control in high frequency on high speed. In this paper, a detail statistical energy analysis (SEA) model is built. And the vibra-acoustic power inputs are loaded on the model for the valid result of car interior noise analysis. The model is the solid foundation for further optimization on car interior noise control. After the most sensitive subsystems for the power contribution to car interior noise are pointed by SEA comprehensive analysis, the sound pressure level of car interior aerodynamic noise can be reduced by improving their sound and damping characteristics. The further vehicle testing results show that it is available to improve the interior acoustic performance by using detailed SEA model, which comprised by more than 80 subsystems, with the unsteady aerodynamic pressure calculation on body surfaces and the materials improvement of sound/damping properties. It is able to acquire more than 2 dB reduction on the central frequency in the spectrum over 800 Hz. The proposed optimization method can be looked as a reference of car interior aerodynamic noise control by the detail SEA model integrated unsteady computational fluid dynamics (CFD) and sensitivity analysis of acoustic contribution. 展开更多
关键词 CAR interior aerodynamic noise control computational fluid dynamics statistical energy analysis
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QTL Analysis for Seven Quality Traits of RIL Population in Japonica Rice Based on Three Genetic Statistical Models 被引量:1
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作者 LIU Qiang-ming JIANG Jian-hua +2 位作者 NIU Fu-an HE Ying-jun HONG De-lin 《Rice science》 SCIE 2013年第1期31-38,共8页
QTL mapping for seven quality traits was conducted by using 254 recombinant inbred lines (RIL) derived from a japonica-japonica rice cross of Xiushui 79/C Bao. The seven traits investigated were grain length (GL),... QTL mapping for seven quality traits was conducted by using 254 recombinant inbred lines (RIL) derived from a japonica-japonica rice cross of Xiushui 79/C Bao. The seven traits investigated were grain length (GL), grain length to width ratio (LWR), chalk grain rate (CGR), chalkiness degree (CD), gelatinization temperature (GT), amylose content (AC) and gel consistency (GC) of head rice. Three mapping methods employed were composite interval mapping in QTLMapper 2.0 software based on mixed linear model (MCIM), inclusive composite interval mapping in QTL IciMapping 3.0 software based on stepwise regression linear model (ICIM) and multiple interval mapping with regression forward selection in Windows QTL Cartographer 2.5 based on multiple regression analysis (MIMR). Results showed that five QTLs with additive effect (A-QTLs) were detected by all the three methods simultaneously, two by two methods simultaneously, and 23 by only one method. Five A-QTLs were detected by MCIM, nine by ICIM and 28 by MIMR. The contribution rates of single A-QTL ranged from 0.89% to 38.07%. All the QTLs with epistatic effect (E-QTLs) detected by MIMR were not detected by the other two methods. Fourteen pairs of E-QTLs were detected by both MCIM and ICIM, and 142 pairs of E-QTLs were detected by only one method. Twenty-five pairs of E-QTLs were detected by MCIM, 141 pairs by ICIM and four pairs by MIMR. The contribution rates of single pair of E-QTL were from 2.60% to 23.78%. In the Xiu-Bao RIL population, epistatic effect played a major role in the variation of GL and CD, and additive effect was the dominant in the variation of LWR, while both epistatic effect and additive effect had equal importance in the variation of CGR, AC, GT and GC. QTLs detected by two or more methods simultaneously were highly reliable, and could be applied to improve the quality traits in japonica hybrid rice. 展开更多
关键词 quantitative trait locus quality trait genetic statistical model japonica rice
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Dynamic Assessment on Regional Eco-environmental Quality Using AHP-Statistics Model—A Case Study of Chaohu Lake Basin 被引量:8
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作者 LI Ruzhong 《Chinese Geographical Science》 SCIE CSCD 2007年第4期341-348,共8页
An indicator system closely connected with eco-environment, in which indicator involves in such fields as society, economy, resources, environment and ecology, is first proposed for eco-environmental quality assessmen... An indicator system closely connected with eco-environment, in which indicator involves in such fields as society, economy, resources, environment and ecology, is first proposed for eco-environmental quality assessment. Then, a hierarchical model with four levels is established by virtue of these indicators and attributes. In the model, weights of indicators and attributes are determined by combining Delphi method with the Analytic Hierarchy Process (AHP) and a statistic method is used to eliminate the influences arising from the differences in dimension and magnitude of indicators. On these grounds, an AHP-statistics model is provided for regional eco-environmental quality assessment. As a case, such AHP-statistics model is utilized in the dynamic analysis of regional eco-environmental assessment in Chaohu Lake basin. Study results show that natural environmental quality in the watershed was in the declining state while social environmental quality was in a markedly improved situation from 1996, and the synthetic eco-environmental quality was gradually and slowly improved under the common influences of both natural and social environmental factors. Example of application testified the capacities of above methodology to evaluate the real and dynamic state of regional eco-environmental quality. 展开更多
关键词 经济-环境质量评价体系 AHP统计模式 湖泊 环境保护
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Multivariate Statistical Process Monitoring and Control: Recent Developments and Applications to Chemical Industry 被引量:39
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作者 梁军 钱积新 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2003年第2期191-203,共13页
Multivariate statistical process monitoring and control (MSPM& C) methods for chemical process monitoring with statistical projection techniques such as principal component analysis (PCA) and partial least squares... Multivariate statistical process monitoring and control (MSPM& C) methods for chemical process monitoring with statistical projection techniques such as principal component analysis (PCA) and partial least squares (PLS) are surveyed in this paper,The four-step procedure of performing MSPM &C for chemical process ,modeling of processes ,detecting abnormal events or faults,identifying the variable(s) responible for the faults and diagnosing the source cause for the abnormal behavior,is analyzed,Several main research directions of MSPM&C reported in the literature are discussed,such as multi-way principal component analysis (MPCA) for batch process ,statistical monitoring and control for nonlinear process,dynamic PCA and dynamic PLS,and on -line quality control by infer-ential models,Industrial applications of MSPM&C to several typical chemical processes ,such as chemical reactor,distillation column,polymeriztion process ,petroleum refinery units,are summarized,Finally,some concluding remarks and future considerations are made. 展开更多
关键词 多变量统计过程监控 化学工业 应用 研究进展
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Assessment of Spatio-Temporal Variations in Water Quality of Shailmari River, Khulna (Bangladesh) Using Multivariate Statistical Techniques 被引量:1
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作者 Md. Muhyminul Islam Olaf K. Lenz +3 位作者 Abul Kalam Azad Mosummath Hosna Ara Masudur Rahman Nazia Hassan 《Journal of Geoscience and Environment Protection》 2017年第1期1-26,共26页
Surface water has become one of the most vulnerable resources on the earth due to deterioration of its quality from diverse sources of pollution. Understanding of the spatiotemporal distribution of pollutants and iden... Surface water has become one of the most vulnerable resources on the earth due to deterioration of its quality from diverse sources of pollution. Understanding of the spatiotemporal distribution of pollutants and identification of the sources in the river systems is a prerequisite for the protection and sustainable utilization of the water resources. Multivariate statistical techniques such as Principal Component Analysis (PCA) and Factor Analysis (FA) were applied in this study to investigate the temporal and spatial variations of water quality and appoint the major factors of pollution in the Shailmari River system. Water quality data for 14 physicochemical parameters from 11 monitoring sites over the year of 2014 in three sampling seasons were collected and analyzed for this study. Kruskal-Wallis test showed significant (p < 0.01) temporal and spatial variations in all of the water quality parameters of the river water. Principal component analysis (PCA) allowed extracting the contributing parameters affecting the seasonal water quality in the river system. Scatter plots of the PCs showed the tidal and spatial variation within river system and identified parameters controlling the behavior in each case. Factor analysis (FA) further reduced the data and extracted factors which are significantly responsible for water quality variation in the river. The results indicate that the parameters controlling the water quality in different seasons are related with salinity, anthropogenic pollution (sewage disposal, effluents) and agricultural runoff in pre-monsoon;precipitation induced surface runoff in monsoon;and erosion, oxidation or organic pollution (point and non-point sources) in post-monsoon. Therefore, the study reveals the applicability and usefulness of the multivariate statistical methods in assessing water quality of river by identifying the potential environmental factors controlling the water quality in different seasons which might help to better understand, monitor and manage the quality of the water resources. 展开更多
关键词 Water quality Variation WASTEWATER MULTIVARIATE statistical Analysis MONSOON BANGLADESH
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A novel Q-based online model updating strategy and its application in statistical process control for rubber mixing 被引量:2
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作者 Chunying Zhang Sun Chen +1 位作者 Fang Wu Kai Song 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第5期796-803,共8页
To overcome the large time-delay in measuring the hardness of mixed rubber, rheological parameters were used to predict the hardness. A novel Q-based model updating strategy was proposed as a universal platform to tra... To overcome the large time-delay in measuring the hardness of mixed rubber, rheological parameters were used to predict the hardness. A novel Q-based model updating strategy was proposed as a universal platform to track time-varying properties. Using a few selected support samples to update the model, the strategy could dramatically save the storage cost and overcome the adverse influence of low signal-to-noise ratio samples. Moreover, it could be applied to any statistical process monitoring system without drastic changes to them, which is practical for industrial practices. As examples, the Q-based strategy was integrated with three popular algorithms(partial least squares(PLS), recursive PLS(RPLS), and kernel PLS(KPLS)) to form novel regression ones, QPLS, QRPLS and QKPLS, respectively. The applications for predicting mixed rubber hardness on a large-scale tire plant in east China prove the theoretical considerations. 展开更多
关键词 控制应用 统计过程 更新策略 炼胶 在线 混合橡胶 过程监控系统 偏最小二乘法
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VPLS Based Quality and Cost Control for Tennessee Eastman Process 被引量:1
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作者 宋凯 王海清 李平 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第1期62-67,共6页
Product quality and operation cost control obtain increasing emphases in modern chemical system engineering. To improve the fault detection power of the partial least square (PLS) method for quality control, a new QRP... Product quality and operation cost control obtain increasing emphases in modern chemical system engineering. To improve the fault detection power of the partial least square (PLS) method for quality control, a new QRPV statistic is proposed in terms of the VP (variable importance in projection) indices of monitored process variables, which is significantly advanced over and different from the conventional Q statistic. QRPV is calculated only by the residuals of the remarkable process variables (RPVs). Therefore, it is the dominant relation between quality and RPV not all process variables (as in the case of the conventional PLS) that is monitored by this new VP-PLS (VPLS) method. The combination of QRPV and T2 statistics is applied to the quality and cost control of the Tennessee Eastman (TE) process, and weak faults can be detected as quickly as possible. Consequently, the product quality of TE process is guaranteed and operation costs are reduced. 展开更多
关键词 产品质量 成本控制系统 化工行业 美国 产品管理 田纳西州
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Application of multivariate statistical techniques in assessment of surface water quality in Second Songhua River basin,China 被引量:3
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作者 郑力燕 于宏兵 王启山 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第5期1040-1051,共12页
Multivariate statistical techniques,such as cluster analysis(CA),discriminant analysis(DA),principal component analysis(PCA) and factor analysis(FA),were applied to evaluate and interpret the surface water quality dat... Multivariate statistical techniques,such as cluster analysis(CA),discriminant analysis(DA),principal component analysis(PCA) and factor analysis(FA),were applied to evaluate and interpret the surface water quality data sets of the Second Songhua River(SSHR) basin in China,obtained during two years(2012-2013) of monitoring of 10 physicochemical parameters at 15 different sites.The results showed that most of physicochemical parameters varied significantly among the sampling sites.Three significant groups,highly polluted(HP),moderately polluted(MP) and less polluted(LP),of sampling sites were obtained through Hierarchical agglomerative CA on the basis of similarity of water quality characteristics.DA identified p H,F,DO,NH3-N,COD and VPhs were the most important parameters contributing to spatial variations of surface water quality.However,DA did not give a considerable data reduction(40% reduction).PCA/FA resulted in three,three and four latent factors explaining 70%,62% and 71% of the total variance in water quality data sets of HP,MP and LP regions,respectively.FA revealed that the SSHR water chemistry was strongly affected by anthropogenic activities(point sources:industrial effluents and wastewater treatment plants;non-point sources:domestic sewage,livestock operations and agricultural activities) and natural processes(seasonal effect,and natural inputs).PCA/FA in the whole basin showed the best results for data reduction because it used only two parameters(about 80% reduction) as the most important parameters to explain 72% of the data variation.Thus,this work illustrated the utility of multivariate statistical techniques for analysis and interpretation of datasets and,in water quality assessment,identification of pollution sources/factors and understanding spatial variations in water quality for effective stream water quality management. 展开更多
关键词 水质评价 统计技术 地表水 松花江流域 非点源污染 城市污水处理厂 应用 统计分析技术
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Integrated Statistical and Engineering Process Control Based on Smooth Transition Autoregressive Model 被引量:1
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作者 张晓蕾 何桢 《Transactions of Tianjin University》 EI CAS 2013年第2期147-156,共10页
Traditional studies on integrated statistical process control and engineering process control (SPC-EPC) are based on linear autoregressive integrated moving average (ARIMA) time series models to describe the dynamic n... Traditional studies on integrated statistical process control and engineering process control (SPC-EPC) are based on linear autoregressive integrated moving average (ARIMA) time series models to describe the dynamic noise of the system.However,linear models sometimes are unable to model complex nonlinear autocorrelation.To solve this problem,this paper presents an integrated SPC-EPC method based on smooth transition autoregressive (STAR) time series model,and builds a minimum mean squared error (MMSE) controller as well as an integrated SPC-EPC control system.The performance of this method for checking the trend and sustained shift is analyzed.The simulation results indicate that this integrated SPC-EPC control method based on STAR model is effective in controlling complex nonlinear systems. 展开更多
关键词 工程过程控制 自回归模型 平滑过渡 综合统计 基础 时间序列模型 综合控制系统 非线性系统
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Evaluation of Groundwater Quality in the Deep Maastrichtian Aquifer of Senegal Using Multivariate Statistics and Water Quality Index-Based GIS
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作者 Djim M. L. Diongue Laila Sagnane +3 位作者 Huguette Emvoutou Maria Faye Ibra D. Gueye Serigne Faye 《Journal of Environmental Protection》 CAS 2022年第11期819-841,共23页
A regional groundwater quality evaluation was conducted in the deep Maastrichtian aquifer of Senegal through multivariate statistical analysis and a GIS-based water quality index using physicochemical data from 232 bo... A regional groundwater quality evaluation was conducted in the deep Maastrichtian aquifer of Senegal through multivariate statistical analysis and a GIS-based water quality index using physicochemical data from 232 boreholes distributed over the whole country. The aim was to 1) identify the water types and likely factors influencing the hydrochemistry, and 2) determine the suitability of groundwater for drinking and irrigation. Results showed that sodium, chloride, and fluoride are highly correlated with electrical conductivity (EC) reflecting the significant contribution of these elements to groundwater mineralization. The principal component analysis evidenced: 1) salinization processes (loaded by Na<sup>+</sup>, K<sup>+</sup>, EC, Cl<sup>-</sup>, F<sup>-</sup> and HCO<sub>3</sub>-</sup>) controlled by water/rock interaction, seawater intrusion and cation exchange reactions;2) dolomite dissolution loaded by the couple Ca<sup>2+</sup> and Mg<sup>2+</sup> and 3) localized mixing with upper aquifers and gypsum dissolution respectively loaded by NO<sub>3</sub>-</sup> and SO<sub>4</sub>2-</sup>. The hierarchical clustering analysis distinguished four clusters: 1) freshwater (EC = 594 μs/cm) with mixed-HCO<sub>3</sub> water type and ionic contents below WHO standard;2) brackish (Na-mixed) water type with moderate mineralization content (1310 μs/cm), 3) brackish (Na-Cl) water type depicted by high EC values (3292 μs/cm) and ionic contents above WHO and 4) saline water with Na-Cl water type and very high mineralization contents (5953 μs/cm). The mapping of the groundwater quality index indicated suitable zones for drinking accounting for 54% of the entire area. The occurrence of a central brackish band and its vicinity, which were characterized by high mineralization, yielded unsuitable groundwater for drinking and agricultural uses. The approach used in this study was valuable for assessing groundwater quality for drinking and irrigation, and it can be used for regional studies in other locations, particularly in shallow and vulnerable aquifers. 展开更多
关键词 Groundwater quality Index MAASTRICHTIAN statistical Analysis GIS
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Statistical Control and Investigation of Capability of Process and Machine in Wire Cut Edm Process of Gas Turbine Blade Airfoil Tip
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作者 Ahmad Reza Fazeli Ebrahim Sharifi 《Engineering(科研)》 2011年第3期260-265,共6页
Statistical process control (spc), as one of the quality devices, can be help manufacturers improve the quality of their products in today’s competitive world. This research examines the statistical method of wire-cu... Statistical process control (spc), as one of the quality devices, can be help manufacturers improve the quality of their products in today’s competitive world. This research examines the statistical method of wire-cut electric discharge machining (WEDM) process of the turbine blade airfoil tip for control and consistency of the process. For this purpose, the standard deviation control chart, S, and the average data, , which are applied for identifying the acquired factors, have been used. Next, regarding the plan features, the manufacturing process is assessed to determine whether the products meet quality and the customer requirements or not. Therefore, the coefficients Cpk is applied which indicate the capability of the manufacturing process. Then, in order to produce high quality blades within the tolerance range, the capability of WEDM machine is examined, using coefficients CM. Finally, it is shown that in order to produce the desired product, the process can be controlled and fixed by using the statistical process control devices and inspecting the standard deviation of data and investigation of capability of process and machine. 展开更多
关键词 statistical PROCESS control WEDM CAPABILITY of PROCESS and MACHINE
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Quality assessment of Jinhongtang Granule using UFLC-MS/MS and multivariate statistical analysis
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作者 Fan Wu Yu Zhang +5 位作者 Yanling Qiao Ting Zhao Baojing Zhang Bangjiang Fang Xiaokui Huo Xiaochi Ma 《Asian Journal of Traditional Medicines》 CAS 2021年第4期191-202,共12页
Jinhongtang is a traditional Chinese medicine formula composed of Rheum palmatum L.stem,Sargentodoxa cuneata stem,and Taraxacum mongolicum and is used for the treatment of sepsis.However,quality assessment method for ... Jinhongtang is a traditional Chinese medicine formula composed of Rheum palmatum L.stem,Sargentodoxa cuneata stem,and Taraxacum mongolicum and is used for the treatment of sepsis.However,quality assessment method for Jinhongtang is not available.In present study,we developed a UFLC-MS/MS method to determine 16 analytes in 20 batches of home-made and commercial Jinhongtang.Multivariate statistical analysis revealed the significant differences in the quality of home-made and commercial Jinhongtang and the difference in the quality of home-made samples was more significant.The integrated strategy based on UFLC-MS/MS and multivariate statistical analysis provided a new basis for the overall quality assessment of Jinhongtang. 展开更多
关键词 Jinhongtang quality assessment UFLC-MS/MS multivariate statistical analysis
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Analysis of the effect of geology, soil properties, and land use on groundwater quality using multivariate statistical and GIS methods
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作者 Jin-Soo Lee Kyung-Seok Ko +3 位作者 Tong-Kwon Kim Jae Gon Kim Seong-Hyun Cho In-Suk Oh 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期152-152,共1页
关键词 地下水 GIS 土壤性质 地质 水质 多元统计
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