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基于实际预压载作业的自升式平台环境载荷图谱绘制新思路
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作者 孙承猛 林海花 +2 位作者 张志刚 孙洪源 周立师 《哈尔滨工程大学学报(英文版)》 CSCD 2024年第1期209-221,共13页
The environmental load chart is an important technical support required for the jack-up drilling platform to facilitate its adaptation to different operating waters and ensure the safety of operation.This chart is a c... The environmental load chart is an important technical support required for the jack-up drilling platform to facilitate its adaptation to different operating waters and ensure the safety of operation.This chart is a crucial part of the platform operation manual.The chart data are closely related to external factors such as water depth,wind,wave,and current conditions of the working water,as well as to the structural characteristics of the platform itself and the number of variable loads.This study examines the platform state under extreme wind,wave,and current conditions during preloading.In addition,this study focuses on the difference between the ultimate reaction force of the pile leg during preloading and the reaction force of the pile leg without considering any environmental load before preloading.Furthermore,the relationship between the difference and the new reaction force of the pile leg caused by the combination of different environmental conditions is established to facilitate the construction of a new form of environmental load chart.The newly formed chart is flexible and simple;thus,it can be used to evaluate the environmental adaptability of the platform in the target well location and provides the preloading target demand or variable load limit according to the given environmental constraints.Moreover,the platform can perform personalized preloading operations,thereby improving its capability to cope with complex geological conditions,such as reducing punch-through risks.This condition reduces the load on jacking system devices and increases its service life. 展开更多
关键词 JACK-UP Environmental load chart PRELOADING Geometrically nonlinear effect Punch through
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Slope stability of reclaimed coal mines through a new water filling index
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作者 Antonios Mikroutsikos Alexandros I.Theocharis +1 位作者 Nikolaos C.Koukouzas Ioannis E.Zevgolis 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第3期828-839,共12页
A common reclamation practice for closed coal surface mines is filling them with water to form pit lakes.The creation and sustainability of these lakes are significantly affected by the stability of the corresponding ... A common reclamation practice for closed coal surface mines is filling them with water to form pit lakes.The creation and sustainability of these lakes are significantly affected by the stability of the corresponding slopes.The present study provides a general framework for analyzing the water filling’s effect on slope stability based on a new water filling index,which can indirectly consider the factors affecting the process and efficiently quantify the filling speed’s influence.The assumptions of the proposed approach are thoroughly discussed,and the range of the water filling index is identified.Furthermore,the safety factor is calculated using the finite element method with the shear strength reduction technique during the filling process for various conditions(soil properties,slope geometry,hydraulic conditions,and water filling speed).Results are presented as normalized stability charts for practical use.During the water filling,the stability gradually decreases until the reservoir reaches a critical level of 10%e40%of the total height;it then increases to even more stable conditions than the initial one.Overall,the present analysis allows for the preliminary stability evaluation of a coal mine during the formation of a pit lake and the appropriate quantification of the water filling’s effect. 展开更多
关键词 Post-coal era Open-pit flooding Stability charts Critical level
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Clinical usefulness of the baby vision test in young children and its correlation with the Snellen chart
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作者 Ya-Lan Wang Jia-Jun Wang +2 位作者 Xi-Cong Lou Han Zou Yun-E Zhao 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第2期348-352,共5页
AIM:To investigate the efficacy of a new visual acuity(VA)screening method,the baby vision test for young children.METHODS:A total 105 eyes of 65 children aged 2-8y were included in the study.Acuity testing was conduc... AIM:To investigate the efficacy of a new visual acuity(VA)screening method,the baby vision test for young children.METHODS:A total 105 eyes of 65 children aged 2-8y were included in the study.Acuity testing was conducted using a standardized recognition acuity chart(Snellen visual chart:at 3 m)and the baby vision model assessment.The baby vision device includes a screen,a near infrared camera and a computer.Children were seated at a measured distance of 33-40 cm from a display for testing.VA was estimated according to the highest resolution the children could follow.Decimal VA data were converted to logarithm of the minimum angle of resolution(logMAR)for statistical analysis.The VA results for each child were recorded and analyzed for consistency.RESULTS:The mean VA measured using the Snellen visual chart was 0.62±0.32,and that assessed using the baby vision test was 0.66±0.27.The 95%limit of agreement was-0.609 to 0.695,with 95.2%(100/105)plots within the 95%limits of agreement.VA values of the baby vision test were significantly correlated with those of the Snellen chart(R=0.274,P=0.005).CONCLUSION:The baby vision test can be used as a relatively reliable method for estimating VA in young children.This new acuity assessment might be a valid predictor of optotype-measured acuity later in preverbal children. 展开更多
关键词 baby vision test acuity assessment fix-and-follow system Snellen chart
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Modified DS np Chart Using Generalized Multiple Dependent State Sampling under Time Truncated Life Test
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作者 Wimonmas Bamrungsetthapong Pramote Charongrattanasakul 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2471-2495,共25页
This study presents the design of a modified attributed control chart based on a double sampling(DS)np chart applied in combination with generalized multiple dependent state(GMDS)sampling to monitor the mean life of t... This study presents the design of a modified attributed control chart based on a double sampling(DS)np chart applied in combination with generalized multiple dependent state(GMDS)sampling to monitor the mean life of the product based on the time truncated life test employing theWeibull distribution.The control chart developed supports the examination of the mean lifespan variation for a particular product in the process of manufacturing.Three control limit levels are used:the warning control limit,inner control limit,and outer control limit.Together,they enhance the capability for variation detection.A genetic algorithm can be used for optimization during the in-control process,whereby the optimal parameters can be established for the proposed control chart.The control chart performance is assessed using the average run length,while the influence of the model parameters upon the control chart solution is assessed via sensitivity analysis based on an orthogonal experimental design withmultiple linear regression.A comparative study was conducted based on the out-of-control average run length,in which the developed control chart offered greater sensitivity in the detection of process shifts while making use of smaller samples on average than is the case for existing control charts.Finally,to exhibit the utility of the developed control chart,this paper presents its application using simulated data with parameters drawn from the real set of data. 展开更多
关键词 Modified DS np chart generalizedmultiple dependent state sampling time truncated life test Weibull distribution average run length average sample size
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Characteristics of carbon isotopic composition of alkane gas in large gas fields in China
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作者 DAI Jinxing NI Yunyan +4 位作者 GONG Deyu HUANG Shipeng LIU Quanyou HONG Feng ZHANG Yanling 《Petroleum Exploration and Development》 SCIE 2024年第2期251-261,共11页
Exploration and development of large gas fields is an important way for a country to rapidly develop its natural gas industry.From 1991 to 2020,China discovered 68 new large gas fields,boosting its annual gas output t... Exploration and development of large gas fields is an important way for a country to rapidly develop its natural gas industry.From 1991 to 2020,China discovered 68 new large gas fields,boosting its annual gas output to 1925×108m3in 2020,making it the fourth largest gas-producing country in the world.Based on 1696 molecular components and carbon isotopic composition data of alkane gas in 70 large gas fields in China,the characteristics of carbon isotopic composition of alkane gas in large gas fields in China were obtained.The lightest and average values ofδ^(13)C_(1),δ13C2,δ13C3andδ13C4become heavier with increasing carbon number,while the heaviest values ofδ^(13)C_(1),δ13C2,δ13C3andδ13C4become lighter with increasing carbon number.Theδ^(13)C_(1)values of large gas fields in China range from-71.2‰to-11.4‰(specifically,from-71.2‰to-56.4‰for bacterial gas,from-54.4‰to-21.6‰for oil-related gas,from-49.3‰to-18.9‰for coal-derived gas,and from-35.6‰to-11.4‰for abiogenic gas).Based on these data,theδ^(13)C_(1)chart of large gas fields in China was plotted.Moreover,theδ^(13)C_(1)values of natural gas in China range from-107.1‰to-8.9‰,specifically,from-1071%o to-55.1‰for bacterial gas,from-54.4‰to-21.6‰for oil-related gas,from-49.3‰to-13.3‰for coal-derived gas,and from-36.2‰to-8.9‰for abiogenic gas.Based on these data,theδ^(13)C_(1)chart of natural gas in China was plotted. 展开更多
关键词 China large gas field bacterial gas oil-related gas coal-derived gas abiogenic gas alkane gas carbon isotopic composition δ^(13)C_(1)chart
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Analysis of Maximum Liquid Carrying Capacity Based on Conventional Tubing Plunger Gas Lift
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作者 Yanqun Yu Wenhao Xu +3 位作者 Yahui Huangfu Jinhai Liu Bensheng Wang Kai Liu 《Energy Engineering》 EI 2024年第6期1521-1533,共13页
China’s unconventional gas fields have a large number of low-productivity and low-efficiency wells, many of whichare located in remote and environmentally harsh mountainous areas. To address the long-term stable prod... China’s unconventional gas fields have a large number of low-productivity and low-efficiency wells, many of whichare located in remote and environmentally harsh mountainous areas. To address the long-term stable productionof these gas wells, plunger-lift technology plays an important role. In order to fully understand and accurately graspthe drainage and gas production mechanisms of plunger-lift, a mechanical model of plunger-liquid column uplift inthe plunger-lift process was established, focusing on conventional plunger-lift systems and representative wellboreconfigurations in the Linxing region. The operating casing pressure of the plunger-lift process and the calculationmethod for the maximum daily fluid production rate based on the work regime with the highest fluid recovery ratewere determined. For the first time, the critical flow rate method was proposed as a constraint for the maximumliquid-carrying capacity of the plunger-lift, and liquid-carrying capacity charts for conventional plunger-lift withdifferent casing sizes were developed. The results showed that for 23/8 casing plunger-lift, with a well depth ofshallower than 808 m, the maximum drainage rate was 33 m3/d;for 27/8 casing plunger-lift, with a well depth ofshallower than 742 m, the maximum drainage rate was 50.15 m3/d;for 31/2 casing plunger-lift, with a well depthof shallower than 560 m, the maximum drainage rate was 75.14 m3/d. This research provides a foundation for thescientific selection of plunger-lift technology and serves as a decision-making reference for developing reasonableplunger-lift work regimes. 展开更多
关键词 Unconventional well conventional tubing string plunger gas lift critical flow rate liquid carry-over chart version
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Exploring Variability in Sea Level at a Tide Gauge Station through Control Charts
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作者 H.Bâkiİz 《Journal of Environmental & Earth Sciences》 CAS 2024年第1期11-18,共8页
Monitoring temporal changes in sea level is important in assessing coastal risk.Sea level anomalies at a tide gauge station,if kinematically conceived,include systematic variations such as trend,acceleration,periodic ... Monitoring temporal changes in sea level is important in assessing coastal risk.Sea level anomalies at a tide gauge station,if kinematically conceived,include systematic variations such as trend,acceleration,periodic oscillations,and random disturbances.Among them,the non-stationary nature of the random sea level variations of known or unknown origin at coastal regions has been long recognized by the sea level community.This study proposes the analyses of subgroups of random residual statistics of a rigorously formulated kinematic model solution of tide gauge variations using X-bar and S control charts.The approach is demonstrated using Key West,Florida tide gauge records.The mean and standard errors of 5-year-long subgroups of the residuals revealed that sea level changes at this location have been progressively intensifying from 1913 to the present.Increasing oscillations in sea level at this locality may be attributed partly to the thermal expansion of seawater with increasing temperatures causing larger buoyancy-related sea level fluctuations as well as the intensification of atmospheric events including wind patterns and the impact of changes in inverted barometer effects that will alter coastal risk assessments for the future. 展开更多
关键词 Climate change Sea level variance X-bar S control charts
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Japanese candlestick charts for diabetes
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作者 Diana Boj-Carceller 《World Journal of Methodology》 2024年第2期167-171,共5页
Continuous glucose monitoring(CGM)is a popular technology among the diabetic population,especially in patients with type 1 diabetes and those with type 2 diabetes treated with insulin.The American Diabetes Association... Continuous glucose monitoring(CGM)is a popular technology among the diabetic population,especially in patients with type 1 diabetes and those with type 2 diabetes treated with insulin.The American Diabetes Association recommends standardization of CGM reports with visual cues,such as the ambulatory glucose profile.Nevertheless,interpreting this report requires training and time for CGM to be cost-efficient.In this work it has been proposed to incorporate Japanese candlestick charts in glucose monitoring.These graphs are used in price analysis in financial markets and are easier to view.Each candle provides extra information to make prudent decisions since it reports the opening,maximum,minimum and closing glucose levels of the chosen time frame,usually the daily one.The Japanese candlestick chart is an interesting tool to be considered in glucose control.This graphic representation allows identification of glucose trends easily through the colors of the candles and maximum and minimum glucose values. 展开更多
关键词 Japanese candlestick chart Candlestick chart Ambulatory glucose profile Glucose monitoring Continuous glucose monitoring HYPOGLYCEMIA
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Selection of Machining Datum and Allocation of Tolerance through Tolerance Charting Technique 被引量:2
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作者 THILAK Manoharan SIVAKUMAR Karuppan JAYAPRAKASH Govindharajalu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第4期697-705,共9页
Tolerance charting is an effective tool to determine the optimal allocation of working dimensions and working tolerances such that the blueprint dimensions and tolerances can be achieved to accomplish the cost objecti... Tolerance charting is an effective tool to determine the optimal allocation of working dimensions and working tolerances such that the blueprint dimensions and tolerances can be achieved to accomplish the cost objectives.The selection of machining datum and allocation of tolerances are critical in any machining process planning as they directly affect any setup methods/machine tools selection and machining time.This paper mainly focuses on the selection of optimum machining datums and machining tolerances simultaneously in process planning.A dynamic tolerance charting constraint scheme is developed and implemented in the optimization procedure.An optimization model is formulated for selecting machining datum and tolerances and implemented with an algorithm namely Elitist Non-Dominated Sorting Genetic Algorithm(NSGA-II).The computational results indicate that the proposed methodology is capable and robust in finding the optimal machining datum set and tolerances. 展开更多
关键词 tolerance allocation tolerance charting elitist non-dominated sorting genetic algorithm-II.
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基于Maritime Charting的内河电子航道图制作优化研究与应用 被引量:2
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作者 路轩轩 赵睿 +1 位作者 赵志明 许宁 《中国水运》 2018年第10期32-35,共4页
本文结合内河电子航道图生产实践,通过分析现有电子航道图生产中存在的诸如人工参与过多、使用软件繁多和生产工序复杂等缺点,总结得出一套全新的电子航道图制作流程和方法。该方法主要包括GDB模板制作、建立满足S-57的物标对应关系等... 本文结合内河电子航道图生产实践,通过分析现有电子航道图生产中存在的诸如人工参与过多、使用软件繁多和生产工序复杂等缺点,总结得出一套全新的电子航道图制作流程和方法。该方法主要包括GDB模板制作、建立满足S-57的物标对应关系等关键技术,涵盖了从数据采集到S-57标准海图文件生成的完整流程,整个过程均在ArcGIS软件中进行,避免了频繁切换应用软件的问题。作者以信阳市南湾水库为研究对象,使用基于Maritime Charting的内河电子航道图制作方法,成功生产出南湾水库电子航道图,证明了该方法的有效性和实用性。 展开更多
关键词 MARITIME charting 内河电子航道图 GDB模板
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On the Charting Procedures: MEWMA Chart and DD-Diagram
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作者 Mekki Hajlaoui 《Open Journal of Statistics》 2015年第5期373-381,共9页
In light of rapid development of customer requirements, control procedures of quality concept use multivariate analysis. This is because of recent advances in information technology and in recording. The charting proc... In light of rapid development of customer requirements, control procedures of quality concept use multivariate analysis. This is because of recent advances in information technology and in recording. The charting procedures are based on Mahalanobis distance but their performance needs normality and a type-I error rate choice. The DD-diagram is an alternative scheme that uses data depth to avoid these conditions rarely met in practice. For a given error-free sample, the performance of DD-diagram and that of multivariate EWMA control procedures are compared through a real example on individual observations taken from a multivariate quality process. 展开更多
关键词 MULTIVARIATE DATA Quality Control Mahalanobis Distance MEWMA CHART DATA Depth DD-Diagram
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Charting a New Path
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作者 Li Li 《ChinAfrica》 2014年第11期14-15,共2页
THE Communist Party of China (CPC) set the blueprint for rule of law in the world's second-largest economy during a recent key meeting, which also high- lighted the Party leadership and the overarching role of the ... THE Communist Party of China (CPC) set the blueprint for rule of law in the world's second-largest economy during a recent key meeting, which also high- lighted the Party leadership and the overarching role of the Constitution in the country's legal system. According to a communique issued after the Fourth Plenary Session of the 18th CPC Central Committee, held in Beijing from October 20 to 23, the overall target of the CPC's current drive is to build a country with socialist rule of law with Chinese characteristics. 展开更多
关键词 In charting a New Path
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Charting the Way Forward China’s lianghui mapped out a promising blueprint for the country’s future development
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作者 Ni Yanshuo 《ChinAfrica》 2018年第4期14-15,共2页
The lianghui, or the annual Two Sessions of the National People's Congress (NPC) and the Chinese People's Political Consultative Conference (CPPCC) National Committee, are always a great political event in China... The lianghui, or the annual Two Sessions of the National People's Congress (NPC) and the Chinese People's Political Consultative Conference (CPPCC) National Committee, are always a great political event in China, but more so this year, with groundbreaking outcomes. 展开更多
关键词 NPC charting the Way Forward China’s lianghui mapped out a promising blueprint for the country’s future development
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An Overview of Narrative Medicine in China 被引量:2
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作者 GUO Liping 《Chinese Medicine and Culture》 2023年第2期205-212,共8页
This paper sketches the history and the author’s involvement in the development of narrative medicine in China.It also describes“narrative medicine with Chinese characteristics,”explaining why narrative medicine is... This paper sketches the history and the author’s involvement in the development of narrative medicine in China.It also describes“narrative medicine with Chinese characteristics,”explaining why narrative medicine is regarded as a tool to materialize the medical humanities in clinical practice,and detailing the features of narrative medicine in China.The features include the wide acceptance of the“22334 model”of narrative medicine,and borrowing theories and practice from Traditional Chinese Medicine.Finally,the author argues that the medical humanities should be given a“Class-A discipline”status,and narrative medicine should be a class-B discipline under the medical humanities. 展开更多
关键词 Class-A discipline Narrative medicine Narrative nursing Parallel chart Medical humanities
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巧用Star Chart软件开展交互式可视化物理教学——以“行星的运动”为例
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作者 文迅 周勋 +1 位作者 周艳 张祥赞 《物理教学探讨》 2023年第1期71-74,共4页
手机软件因其性能优良、携带方便等优点,是实现交互式可视化物理教学的得力助手。探讨了利用手机软件“Star Chart”开展交互式可视化物理教学的三个方法:模型与过程可视化、尺度与角度交互、信息共享交互,可为教师开展交互式可视化教... 手机软件因其性能优良、携带方便等优点,是实现交互式可视化物理教学的得力助手。探讨了利用手机软件“Star Chart”开展交互式可视化物理教学的三个方法:模型与过程可视化、尺度与角度交互、信息共享交互,可为教师开展交互式可视化教学提供参考。 展开更多
关键词 Star Chart 交互式可视化 行星的运动
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A systematic review of reading tests
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作者 Panagiota Ntonti Christina Mitsi +4 位作者 Eleftherios Chatzimichael Eirini-Kanella Panagiotopoulou Minas Bakirtzis Aristeidis Konstantinidis Georgios Labiris 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第1期121-127,共7页
Adequate near and intermediate visual capacity is important in performing everyday tasks,especially after the introduction of smartphones and computers in our professional and recreational activities.Primary objective... Adequate near and intermediate visual capacity is important in performing everyday tasks,especially after the introduction of smartphones and computers in our professional and recreational activities.Primary objective of this study was to review all available reading tests both conventional and digital and explore their integrated characteristics.A systematic review of the recent literature regarding reading charts was performed based on the PubM ed,Google Scholar,and Springer databases between February and March 2021.Data from 11 descriptive and 24 comparative studies were included in the present systematic review.Clinical settings are still dominated by conventional printed reading charts;however,the most prevalent of them(i.e.,Jaeger type charts)are not validated.Reliable reading capacity assessment is done only by those that comply with the International Council of Ophthalmology(ICO)recommendations.Digital reading tests are gaining popularity both in clinical and research settings and are differentiated in standard computer-based applications that require installation either in a computer or a tablet(e.g.,Advanced VISION Test and web-based ones e.g.,Democritus Digital Acuity Reading Test requires no installation).It is evident that validated digital tests will prevail in future clinical or research settings and it is upon ophthalmologists to select the one most compatible with their examination routine. 展开更多
关键词 digital reading chart paper reading chart PRESBYOPIA low vision chart reading acuity
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Effect of Measurement Error on the Multivariate CUSUM Control Chart for Compositional Data
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作者 Muhammad Imran Jinsheng Sun +2 位作者 Fatima Sehar Zaidi Zameer Abbas Hafiz Zafar Nazir 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第8期1207-1257,共51页
Control charts(CCs)are one of the main tools in Statistical Process Control that have been widely adopted in manufacturing sectors as an effective strategy for malfunction detection throughout the previous decades.Mea... Control charts(CCs)are one of the main tools in Statistical Process Control that have been widely adopted in manufacturing sectors as an effective strategy for malfunction detection throughout the previous decades.Measurement errors(M.E’s)are involved in the quality characteristic of interest,which can effect the CC’s performance.The authors explored the impact of a linearmodel with additive covariate M.E on the multivariate cumulative sum(CUSUM)CC for a specific kind of data known as compositional data(CoDa).The average run length(ARL)is used to assess the performance of the proposed chart.The results indicate that M.E’s significantly affects themultivariate CUSUM-CoDaCCs.The authors haveused theMarkov chainmethod to study the impact of different involved parameters using six different cases for the variance-covariance matrix(VCM)(i.e.,uncorrelated with equal variances,uncorrelated with unequal variances,positively correlated with equal variances,positively correlated with unequal variances,negatively correlatedwith equal variances and negatively correlated with unequal variances).The authors concluded that the error VCM has a negative impact on the performance of themultivariate CUSUM-CoDa CC,as the ARL increases with an increase in the value of the error VCM.The subgroup size m and powering operator b positively impact the proposed CC,as the ARL decreases with an increase in m or b.The number of variables p also has a negative impact on the performance of the proposed CC,as the values of ARL increase with an increase in p.For the implementation of the proposal,two illustrated examples have been reported formultivariate CUSUM-CoDaCCs inthe presence ofM.E’s.Onedealswith themanufacturingprocessof uncoated aspirin tablets,and the other is based on monitoring the machines involved in the muesli manufacturing process. 展开更多
关键词 MCUSUM chart CODA measurement error manufacturing process PERFORMANCE
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Ranked-Set Sampling Based Distribution Free Control Chart with Application in CSTR Process
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作者 Ibrahim M.Almanjahie Zahid Rasheed +2 位作者 Majid Khan Syed Masroor Anwar Ammara Nawaz Cheema 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第6期2091-2118,共28页
Nonparametric(distribution-free)control charts have been introduced in recent years when quality characteristics do not follow a specific distribution.When the sample selection is prohibitively expensive,we prefer ran... Nonparametric(distribution-free)control charts have been introduced in recent years when quality characteristics do not follow a specific distribution.When the sample selection is prohibitively expensive,we prefer ranked-set sampling over simple random sampling because ranked set sampling-based control charts outperform simple random sampling-based control charts.In this study,we proposed a nonparametric homogeneously weighted moving average based on theWilcoxon signed-rank test with ranked set sampling(NPHWMARSS)control chart for detecting shifts in the process location of a continuous and symmetric distribution.Monte Carlo simulations are used to obtain the run length characteristics to evaluate the performance of the proposed NPHWMARSS control chart.The proposed NPHWMARSS control chart’s performance is compared to that of parametric and nonparametric control charts.These control charts include the exponentially weighted moving average(EWMA)control chart,Wilcoxon signed-rank with simple random sampling based the nonparametric EWMA control chart,the nonparametric EWMA sign control chart,Wilcoxon signed-rank with ranked set sampling-based the nonparametric EWMA control chart,and the homogeneously weighted moving average control charts.The findings show that the proposed NPHWMARSS control chart performs better than its competitors,particularly for the small shifts.Finally,an example is presented to demonstrate how the proposed scheme can be implemented practically. 展开更多
关键词 Nonparametric control charts RUN-LENGTH ranked set sampling Wilcoxon signed-rank
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Contributions of annual and semiannual tidal constituents to chart datum in the China seas and adjacent waters
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作者 Yikai Feng Yanguang Fu +1 位作者 Long Yang Dongxu Zhou 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第10期127-136,共10页
Global uniform chart datum(CD)surface construction is the basic upon which to realize various vertical datums transformation,and is of great importance for geospatial data expression under the same vertical datum.Gene... Global uniform chart datum(CD)surface construction is the basic upon which to realize various vertical datums transformation,and is of great importance for geospatial data expression under the same vertical datum.Generally,the CD level is computed by developing the function between tidal constituents’harmonic constants and time,i.e.,the lowest astronomical tide is taken as the lowest predicted tide level by adopting the major constituents over a 19-a period.The CD surface prescribed in China is the theoretical lowest tide(TLT)and is calculated using 13 tidal constituents,i.e.,short-period(Q_(1),O_(1),P_(1),K_(1),N_(2),M_(2),S_(2),K_(2),M_(4),MS_(4)and M_(6))and long-period(Sa and Ssa)tidal constituents.Although the accuracy in determining short-period tidal constituents has improved gradually,the long-period tide has not been studied thoroughly owing to nonstationary and temporal variations.Previous studies have intended to evaluate the effect of Sa and Ssa tides in the determination of the TLT level for the purpose of determining a more accurate CD surface for the China seas and adjacent waters.Here,the parameters of long-period tidal correction and long-period tidal correction rate were treated as the effect of both Sa and Ssa on the TLT,and the TOPEX/Poseidon and Jason series satellite altimetry data ranged from October 1992 to April 2022 were adopted to analyze the contribution of long-period tidal constituents.Results showed that the average long-period correction value is 10.10 cm(range from 8.57 cm to 14.98 cm),and that the average long-period tidal contribution rate is 14.56%(range from 9.09%to 23.97%)in the China seas and adjacent waters.Finally,data from 82 tide gauge station with at least a 1-a record of hourly observations were compared with satellite-derived result.We concluded that the long-period tidal contribution should not be neglected in TLT construction.Furthermore,to reduce tidal datum uncertainty,accurate extraction of long-period tidal constituents should receive closer attentions. 展开更多
关键词 tidal datum chart datum long-period tidal constituent lowest normal low water China seas and adjacent waters
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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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