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
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
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
Introduction Since De Montbeillard characterized the first curve of his son's height in the late 18th century,growth charts have become increasingly essential for pediatricians to describe group-level variability ...Introduction Since De Montbeillard characterized the first curve of his son's height in the late 18th century,growth charts have become increasingly essential for pediatricians to describe group-level variability and monitor the over-development of individual-level growth[1].Growth charts can provide a standardized statistical reference to estimate deviations in a child's physiological measurements(e.g.,height and weight).展开更多
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
China’s development plan is expected to highlight new priorities rather than high growth rates China aims to achieve"major breakthroughs"in economic restructuring and will take reform as"a powerful dri...China’s development plan is expected to highlight new priorities rather than high growth rates China aims to achieve"major breakthroughs"in economic restructuring and will take reform as"a powerful driving force" to accelerate the transformation of its economic development pattern.The Central Committee of the Communist Party展开更多
China’s once-in-a-decade census will release information essential for making strategic policies China is updating its demographic information through its once-in-a-decade population census. The
On March 7, Chinese Foreign Minister Yang Jiechi spoke to Chinese and foreign media at a press conference at the Fourth Session of the 11th National People’s Congress. Edited highlights follow:
Introduction In this article we discuss making use of applied linguistic theory, as the means of achieving national standards at tertiary level. We contest that methods now widely in use at colleges and universities a...Introduction In this article we discuss making use of applied linguistic theory, as the means of achieving national standards at tertiary level. We contest that methods now widely in use at colleges and universities are insufficient to reach modern nationwide targets. We suggest modifications in teaching approach and present ideas for supplementing and enlivening existing materials or replacing them. Much of the article is drawn from our converging experiences both as a Chinese university teacher of English from one aspect and as an English EFL specialist from another. We speak jointly from the ’chalkface’ and wish to share our views and be provoked into seeking solutions to the new challenges for Chinese EFL inherent in targets set by the national standards.展开更多
Brain growth charts and age-normed brain templates are essential resources for researchers to eventually contribute to the care of individuals with atypical developmental trajectories.The present work generates age-no...Brain growth charts and age-normed brain templates are essential resources for researchers to eventually contribute to the care of individuals with atypical developmental trajectories.The present work generates age-normed brain templates for children and adolescents at one-year intervals and the corresponding growth charts to investigate the influences of age and ethnicity using a common pediatric neuroimaging protocol.Two accelerated longitudinal cohorts with the identical experimental design were implemented in the United States and China.Anatomical magnetic resonance imaging(MRI)of typically developing school-age children(TDC)was obtained up to three times at nominal intervals of1.25 years.The protocol generated and compared population-and age-specific brain templates and growth charts,respectively.A total of 674 Chinese pediatric MRI scans were obtained from 457 Chinese TDC and 190 American pediatric MRI scans were obtained from 133 American TDC.Population-and age-specific brain templates were used to quantify warp cost,the differences between individual brains and brain templates.Volumetric growth charts for labeled brain network areas were generated.Shape analyses of cost functions supported the necessity of age-specific and ethnicitymatched brain templates,which was confirmed by growth chart analyses.These analyses revealed volumetric growth differences between the two ethnicities primarily in lateral frontal and parietal areas,regions which are most variable across individuals in regard to their structure and function.Age-and ethnicity-specific brain templates facilitate establishing unbiased pediatric brain growth charts,indicating the necessity of the brain charts and brain templates generated in tandem.These templates and growth charts as well as related codes have been made freely available to the public for open neuroscience(https://github.com/zuoxinian/CCS/tree/master/H3/Growth Charts).展开更多
Natural gas hydrates(hereinafter referred to as hydrates)are a promising clean energy source.However,their current development is far from reaching commercial exploitation.Reservoir stimulation tech-nology provides ne...Natural gas hydrates(hereinafter referred to as hydrates)are a promising clean energy source.However,their current development is far from reaching commercial exploitation.Reservoir stimulation tech-nology provides new approaches to enhance hydrate development effectiveness.Addressing the current lack of quantitative and objective methods for evaluating the fracability of hydrate reservoirs,this study clarifies the relationship between geological and engineering fracability and proposes a comprehensive evaluation model for hydrate reservoir fracability based on grey relational analysis and the criteria importance through intercriteria correlation method.By integrating results from hydraulic fracturing experiments on hydrate sediments,the fracability of hydrate reservoirs is assessed.The concept of critical construction parameter curves for hydrate reservoirs is introduced for the first time.Additionally,two-dimensional fracability index evaluation charts and three-dimensional fracability construction condition discrimination charts are established.The results indicate that as the comprehensive fracability index increases,the feasibility of forming fractures in hydrate reservoirs improves,and the required normalized fracturing construction parameters gradually decrease.The accuracy rate of the charts in judging experimental results reached 89.74%,enabling quick evaluations of whether hydrate reservoirs are worth fracturing,easy to fracture,and capable of being fractured.This has significant engineering implications forthehydraulicfracturingof hydratereservoirs.展开更多
In the context of post-stimulation shale gas wells,the terms“shut-in”and“flowback”refer to two critical phases that occur after hydraulic fracturing(fracking)has been completed.These stages play a crucial role in ...In the context of post-stimulation shale gas wells,the terms“shut-in”and“flowback”refer to two critical phases that occur after hydraulic fracturing(fracking)has been completed.These stages play a crucial role in determining both the well’s initial production performance and its long-term hydrocarbon recovery.By establishing a comprehensive big data analysis platform,the flowback dynamics of over 1000 shale gas wells were analyzed in this work,leading to the development of an index system for evaluating flowback production capacity.Additionally,a shut-in chart was created for wells with different types of post-stimulation fracture networks,providing a structured approach to optimizing production strategies.A dynamic analysis method for flowback was also developed,using daily pressure drop and artificial fracture conductivity as key indicators.This method offers a systematic and effective approach to managing the shut-in and flowback processes for gas wells.Field trials demonstrated significant improvements:the probability of sand production was reduced,gas breakthrough time was extended,artificial fracture conductivity was enhanced,and the average estimated ultimate recovery(EUR)per well increased.展开更多
Geological strength index(GSI)has been widely used as an input parameter in predicting the strength and deformation properties of rock masses.This study derived a series of equations to satisfy the original GSI lines ...Geological strength index(GSI)has been widely used as an input parameter in predicting the strength and deformation properties of rock masses.This study derived a series of equations to satisfy the original GSI lines on the basic GSI chart.Two axes ranging from 0 to 100 were employed for surface conditions of the discontinuities and the structure of rock mass,which are independent of the input parameters.The derived equations can analyze GSI values ranging from 0 to 100 within±5%error.The engineering dimensions(EDs)such as the slope height,tunnel width,and foundation width were used together with representative elementary volume(REV)in jointed rock mass to define scale factor(sf)from 0.2 to 1 in evaluating the rock mass structure including joint pattern.The transformation of GSI into a scaledependent parameter based on engineering scale addresses a crucial requirement in various engineering applications.The improvements proposed in this study were applied to a real slope which was close to the time of failure.The results of stability assessments show that the new proposals have sufficient capability to define rock mass quality considering EDs.展开更多
This study aims to examine the explicit solution for calculating the Average Run Length(ARL)on the triple exponentially weighted moving average(TEWMA)control chart applied to autoregressive model(AR(p)),where AR(p)is ...This study aims to examine the explicit solution for calculating the Average Run Length(ARL)on the triple exponentially weighted moving average(TEWMA)control chart applied to autoregressive model(AR(p)),where AR(p)is an autoregressive model of order p,representing a time series with dependencies on its p previous values.Additionally,the study evaluates the accuracy of both explicit and numerical integral equation(NIE)solutions for AR(p)using the TEWMA control chart,focusing on the absolute percentage relative error.The results indicate that the explicit and approximate solutions are in close agreement.Furthermore,the study investigates the performance of exponentially weighted moving average(EWMA)and TEWMA control charts in detecting changes in the process,using the relative mean index(RMI)as a measure.The findings demonstrate that the TEWMA control chart outperforms the EWMA control chart in detecting process changes,especially when the value ofλis sufficiently large.In addition,an analysis using historical data from the SET index between January 2024 and May 2024 and historical data of global annual plastic production,the results of both data sets also emphasize the superior performance of the TEWMA control chart.展开更多
We use transaction-level data from the Bitcoin exchange Mt.Gox,including over 1.4 million transactions from more than 45,000 traders,to investigate the role of technical chart patterns in the early Bitcoin market from...We use transaction-level data from the Bitcoin exchange Mt.Gox,including over 1.4 million transactions from more than 45,000 traders,to investigate the role of technical chart patterns in the early Bitcoin market from April 2011 to September 2013.Employing a pattern recognition algorithm,we identify hourly trading signals for five major chart patterns.Buy signals of these patterns are associated with an average increase in abnormal trading volume of more than 53%.Trades executed during buy signal periods yield significantly higher average returns than those made during non-signal periods.Traders who use chart patterns more frequently are more likely to generate right-skewed return distributions,engage in more active trading,and achieve higher average roundtrip returns.Our research suggests that chart pattern trading was a crucial tool for Mt.Gox clients,highlighting the importance of technical heuristics in shaping the dynamics in a less efficient and unregulated market environment.By leveraging a comprehensive transaction dataset from a major cryptocurrency exchange,we provide unique insights into the actual trading behavior of the first Bitcoin adopters.This sets our work apart from previous studies that mainly rely on backtesting technical strategies using publicly available price data.展开更多
This study proposes a novel approach to optimizing individual work schedules for book digitization using mixed-integer programming (MIP). By leveraging the power of MIP solvers, we aimed to minimize the overall digiti...This study proposes a novel approach to optimizing individual work schedules for book digitization using mixed-integer programming (MIP). By leveraging the power of MIP solvers, we aimed to minimize the overall digitization time while considering various constraints and process dependencies. The book digitization process involves three key steps: cutting, scanning, and binding. Each step has specific requirements and limitations such as the number of pages that can be processed simultaneously and potential bottlenecks. To address these complexities, we formulate the problem as a one-machine job shop scheduling problem with additional constraints to capture the unique characteristics of book digitization. We conducted a series of experiments to evaluate the performance of our proposed approach. By comparing the optimized schedules with the baseline approach, we demonstrated significant reductions in the overall processing time. In addition, we analyzed the impact of different weighting schemes on the optimization results, highlighting the importance of identifying and prioritizing critical processes. Our findings suggest that MIP-based optimization can be a valuable tool for improving the efficiency of individual work schedules, even in seemingly simple tasks, such as book digitization. By carefully considering specific constraints and objectives, we can save time and leverage resources by carefully considering specific constraints and objectives.展开更多
文摘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.
文摘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.
文摘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.
基金supported by Beijing Natural Science Funds for Distinguished Young Scholars(JQ20036)Fundamental Research Funds for the Central Universities(No.2021XD-A03-1).
文摘Introduction Since De Montbeillard characterized the first curve of his son's height in the late 18th century,growth charts have become increasingly essential for pediatricians to describe group-level variability and monitor the over-development of individual-level growth[1].Growth charts can provide a standardized statistical reference to estimate deviations in a child's physiological measurements(e.g.,height and weight).
文摘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.
文摘China’s development plan is expected to highlight new priorities rather than high growth rates China aims to achieve"major breakthroughs"in economic restructuring and will take reform as"a powerful driving force" to accelerate the transformation of its economic development pattern.The Central Committee of the Communist Party
文摘China’s once-in-a-decade census will release information essential for making strategic policies China is updating its demographic information through its once-in-a-decade population census. The
文摘On March 7, Chinese Foreign Minister Yang Jiechi spoke to Chinese and foreign media at a press conference at the Fourth Session of the 11th National People’s Congress. Edited highlights follow:
文摘Introduction In this article we discuss making use of applied linguistic theory, as the means of achieving national standards at tertiary level. We contest that methods now widely in use at colleges and universities are insufficient to reach modern nationwide targets. We suggest modifications in teaching approach and present ideas for supplementing and enlivening existing materials or replacing them. Much of the article is drawn from our converging experiences both as a Chinese university teacher of English from one aspect and as an English EFL specialist from another. We speak jointly from the ’chalkface’ and wish to share our views and be provoked into seeking solutions to the new challenges for Chinese EFL inherent in targets set by the national standards.
基金the Beijing Municipal Science and Tech Commission(Z161100002616023,Z171100000117012,Z181100001518003)the National Natural Science Foundation of China(81220108014)+4 种基金the China-Netherlands CAS-NWO Programme(153111KYSB20160020)the National R&D Infrastructure and Facility Development Program of China,Fundamental Science Data Sharing Platform(DKA2020-12-02-21)the Startup Funds for Leading Talents at Beijing Normal University,Guangxi Ba Gui Scholarship(201621)the Key Realm R&D Program of Guangdong Province(2019B030335001)funded by the Singapore National Research Foundation(NRF)Fellowship(Class of 2017)。
文摘Brain growth charts and age-normed brain templates are essential resources for researchers to eventually contribute to the care of individuals with atypical developmental trajectories.The present work generates age-normed brain templates for children and adolescents at one-year intervals and the corresponding growth charts to investigate the influences of age and ethnicity using a common pediatric neuroimaging protocol.Two accelerated longitudinal cohorts with the identical experimental design were implemented in the United States and China.Anatomical magnetic resonance imaging(MRI)of typically developing school-age children(TDC)was obtained up to three times at nominal intervals of1.25 years.The protocol generated and compared population-and age-specific brain templates and growth charts,respectively.A total of 674 Chinese pediatric MRI scans were obtained from 457 Chinese TDC and 190 American pediatric MRI scans were obtained from 133 American TDC.Population-and age-specific brain templates were used to quantify warp cost,the differences between individual brains and brain templates.Volumetric growth charts for labeled brain network areas were generated.Shape analyses of cost functions supported the necessity of age-specific and ethnicitymatched brain templates,which was confirmed by growth chart analyses.These analyses revealed volumetric growth differences between the two ethnicities primarily in lateral frontal and parietal areas,regions which are most variable across individuals in regard to their structure and function.Age-and ethnicity-specific brain templates facilitate establishing unbiased pediatric brain growth charts,indicating the necessity of the brain charts and brain templates generated in tandem.These templates and growth charts as well as related codes have been made freely available to the public for open neuroscience(https://github.com/zuoxinian/CCS/tree/master/H3/Growth Charts).
基金support of the National Natural Science Foundation of China(Grant No.52074332).
文摘Natural gas hydrates(hereinafter referred to as hydrates)are a promising clean energy source.However,their current development is far from reaching commercial exploitation.Reservoir stimulation tech-nology provides new approaches to enhance hydrate development effectiveness.Addressing the current lack of quantitative and objective methods for evaluating the fracability of hydrate reservoirs,this study clarifies the relationship between geological and engineering fracability and proposes a comprehensive evaluation model for hydrate reservoir fracability based on grey relational analysis and the criteria importance through intercriteria correlation method.By integrating results from hydraulic fracturing experiments on hydrate sediments,the fracability of hydrate reservoirs is assessed.The concept of critical construction parameter curves for hydrate reservoirs is introduced for the first time.Additionally,two-dimensional fracability index evaluation charts and three-dimensional fracability construction condition discrimination charts are established.The results indicate that as the comprehensive fracability index increases,the feasibility of forming fractures in hydrate reservoirs improves,and the required normalized fracturing construction parameters gradually decrease.The accuracy rate of the charts in judging experimental results reached 89.74%,enabling quick evaluations of whether hydrate reservoirs are worth fracturing,easy to fracture,and capable of being fractured.This has significant engineering implications forthehydraulicfracturingof hydratereservoirs.
基金PetroChina Research Applied Science and Technology Project,“Shale Gas Scale Increase Production and Exploration andDevelopment Technology-Research and Application of Key Technology of Deep Shale Gas Scale Production”(No.2023ZZ21YJ01).
文摘In the context of post-stimulation shale gas wells,the terms“shut-in”and“flowback”refer to two critical phases that occur after hydraulic fracturing(fracking)has been completed.These stages play a crucial role in determining both the well’s initial production performance and its long-term hydrocarbon recovery.By establishing a comprehensive big data analysis platform,the flowback dynamics of over 1000 shale gas wells were analyzed in this work,leading to the development of an index system for evaluating flowback production capacity.Additionally,a shut-in chart was created for wells with different types of post-stimulation fracture networks,providing a structured approach to optimizing production strategies.A dynamic analysis method for flowback was also developed,using daily pressure drop and artificial fracture conductivity as key indicators.This method offers a systematic and effective approach to managing the shut-in and flowback processes for gas wells.Field trials demonstrated significant improvements:the probability of sand production was reduced,gas breakthrough time was extended,artificial fracture conductivity was enhanced,and the average estimated ultimate recovery(EUR)per well increased.
文摘Geological strength index(GSI)has been widely used as an input parameter in predicting the strength and deformation properties of rock masses.This study derived a series of equations to satisfy the original GSI lines on the basic GSI chart.Two axes ranging from 0 to 100 were employed for surface conditions of the discontinuities and the structure of rock mass,which are independent of the input parameters.The derived equations can analyze GSI values ranging from 0 to 100 within±5%error.The engineering dimensions(EDs)such as the slope height,tunnel width,and foundation width were used together with representative elementary volume(REV)in jointed rock mass to define scale factor(sf)from 0.2 to 1 in evaluating the rock mass structure including joint pattern.The transformation of GSI into a scaledependent parameter based on engineering scale addresses a crucial requirement in various engineering applications.The improvements proposed in this study were applied to a real slope which was close to the time of failure.The results of stability assessments show that the new proposals have sufficient capability to define rock mass quality considering EDs.
基金the National Science,Research and Innovation Fund(NSRF)King Mongkuts University of Technology North Bangkok under contract no.KMUTNB-FF-68-B-08.
文摘This study aims to examine the explicit solution for calculating the Average Run Length(ARL)on the triple exponentially weighted moving average(TEWMA)control chart applied to autoregressive model(AR(p)),where AR(p)is an autoregressive model of order p,representing a time series with dependencies on its p previous values.Additionally,the study evaluates the accuracy of both explicit and numerical integral equation(NIE)solutions for AR(p)using the TEWMA control chart,focusing on the absolute percentage relative error.The results indicate that the explicit and approximate solutions are in close agreement.Furthermore,the study investigates the performance of exponentially weighted moving average(EWMA)and TEWMA control charts in detecting changes in the process,using the relative mean index(RMI)as a measure.The findings demonstrate that the TEWMA control chart outperforms the EWMA control chart in detecting process changes,especially when the value ofλis sufficiently large.In addition,an analysis using historical data from the SET index between January 2024 and May 2024 and historical data of global annual plastic production,the results of both data sets also emphasize the superior performance of the TEWMA control chart.
文摘We use transaction-level data from the Bitcoin exchange Mt.Gox,including over 1.4 million transactions from more than 45,000 traders,to investigate the role of technical chart patterns in the early Bitcoin market from April 2011 to September 2013.Employing a pattern recognition algorithm,we identify hourly trading signals for five major chart patterns.Buy signals of these patterns are associated with an average increase in abnormal trading volume of more than 53%.Trades executed during buy signal periods yield significantly higher average returns than those made during non-signal periods.Traders who use chart patterns more frequently are more likely to generate right-skewed return distributions,engage in more active trading,and achieve higher average roundtrip returns.Our research suggests that chart pattern trading was a crucial tool for Mt.Gox clients,highlighting the importance of technical heuristics in shaping the dynamics in a less efficient and unregulated market environment.By leveraging a comprehensive transaction dataset from a major cryptocurrency exchange,we provide unique insights into the actual trading behavior of the first Bitcoin adopters.This sets our work apart from previous studies that mainly rely on backtesting technical strategies using publicly available price data.
文摘This study proposes a novel approach to optimizing individual work schedules for book digitization using mixed-integer programming (MIP). By leveraging the power of MIP solvers, we aimed to minimize the overall digitization time while considering various constraints and process dependencies. The book digitization process involves three key steps: cutting, scanning, and binding. Each step has specific requirements and limitations such as the number of pages that can be processed simultaneously and potential bottlenecks. To address these complexities, we formulate the problem as a one-machine job shop scheduling problem with additional constraints to capture the unique characteristics of book digitization. We conducted a series of experiments to evaluate the performance of our proposed approach. By comparing the optimized schedules with the baseline approach, we demonstrated significant reductions in the overall processing time. In addition, we analyzed the impact of different weighting schemes on the optimization results, highlighting the importance of identifying and prioritizing critical processes. Our findings suggest that MIP-based optimization can be a valuable tool for improving the efficiency of individual work schedules, even in seemingly simple tasks, such as book digitization. By carefully considering specific constraints and objectives, we can save time and leverage resources by carefully considering specific constraints and objectives.
