This paper analyzes the effect of subgroup size on the x-bar chart characteristics using sample influx (SIF) into forensic science laboratory (FSL). The characteristics studied include changes in out-or-control points...This paper analyzes the effect of subgroup size on the x-bar chart characteristics using sample influx (SIF) into forensic science laboratory (FSL). The characteristics studied include changes in out-or-control points (OCP), upper control limit UCLx, and zonal demarcations. Multi-rules were used to identify the number of out-of-control-points, Nocp as violations using five control chart rules applied separately. A sensitivity analysis on the Nocp was applied for subgroup size, k, and number of sigma above the mean value to determine the upper control limit, UCLx. A computer code was implemented using a FORTRAN code to create x-bar control-charts and capture OCP and other control-chart characteristics with increasing k from 2 to 25. For each value of k, a complete series of average values, Q(p), of specific length, Nsg, was created from which statistical analysis was conducted and compared to the original SIF data, S(t). The variation of number of out-of-control points or violations, Nocp, for different control-charts rules with increasing k was determined to follow a decaying exponential function, Nocp = Ae–α, for which, the goodness of fit was established, and the R2 value approached unity for Rule #4 and #5 only. The goodness of fit was established to be the new criteria for rational subgroup-size range, for Rules #5 and #4 only, which involve a count of 6 consecutive points decreasing and 8 consecutive points above the selected control limit (σ/3 above the grand mean), respectively. Using this criterion, the rational subgroup range was established to be 4 ≤ k ≤ 20 for the two x-bar control chart rules.展开更多
Fast depletion of fossil fuels with its resources already passed its mid depletion region and the pollution levels already reached unsafe levels which make it utmost necessity to search for alternative fuels to meet s...Fast depletion of fossil fuels with its resources already passed its mid depletion region and the pollution levels already reached unsafe levels which make it utmost necessity to search for alternative fuels to meet sustainable energy demand with minimum environmental impact. Among alternative fuels, hydrogen is considered as the near future, long term renewable, sustainable and non-polluting fuel. In the present paper, hydrogen fueled internal combustion engine fundamentals highlighted and presented relating to hydrogen combustion properties. A Mat lab programmed hydrogen temperature-entropy-energy chart is developed and presented for fresh charge and products of combustion at different excess air factors per mole combustion gases. The chart, then, used to represent a SI hydrogen-fueled fuel/air cycle analysis, which proved to be valuable design tool for engine sizing and for prediction of engine performance. Predictions carried out using the hydrogen F/A cycle analysis at different λ show low brake specific fuel consumption and low volume specific power compared with conventional SI engine.展开更多
The main purpose of this study was to carry out the DACUM(developing a curriculum)analysis in studying the job functions for digital media designers in Taiwan,China as a case study.The primary tasks were twofold:(A)St...The main purpose of this study was to carry out the DACUM(developing a curriculum)analysis in studying the job functions for digital media designers in Taiwan,China as a case study.The primary tasks were twofold:(A)Study the DACUM Occupational Analysis'connotation and(B)Investigate the outputs of the DACUM Occupational Analysis and establish a job function profile for digital media designers.The research method included(a)Literature Review,to review and discuss the connotation of DACUM Occupational Analysis and(b)Comparative Study,in which a variety of charts of the occupational analysis obtained from the Literature Review were compared to reach conclusions.In summary,various DACUM charts obtained from literature reviews on digital media design jobs appeared significantly different in contents of the charts.Therefore,in any future and consecutive DACUM Occupational Analysis,exiting DACUM Charts could be referenced as the starting point for the DACUM process;then the parameters such as the number of facilitators,panelists,number of tasks,job function duties,personal traits,tools and attributes,etc.should be reviewed and optimized depending on the actual requirement,local development,cultural background,local training and educational levels,etc..Hopefully the case study in establishing the job function descriptions for digital media designers in Taiwan,China presented in the Conclusion Section of this report has demonstrated this process satisfactorily.展开更多
In the stainless steel 304 （SUS 304） wire drawing process, optimizing the die life and wire tensile strength, which are the larger-the-better quality characteristics （QCH） types, is of main interest. Three control...In the stainless steel 304 （SUS 304） wire drawing process, optimizing the die life and wire tensile strength, which are the larger-the-better quality characteristics （QCH） types, is of main interest. Three control factors, involving reduction ratio, lubricant temperature, and drawing speed, were investigated utilizing L9（34） orthogonal array （OA）. The grey relational analysis was conducted for the normalized signal-to-noise （S/N） ratios. The ordinal value of the grey grade was then used to decide optimal factor levels. The anticipated improvements in die life and wire tensile strength were estimated 25.31 h and 22.50 kg/mm2, respectively. To decide the significant factor which had effect on each QCH and predict the average value of each QCH, analysis of variance （ANOVA） was performed for S/N ratio and QCH. Confirmation experiments were then conducted, where a good overlap was noticed between the predicted and confirnation intervals for each QCH. The Hotelling T2 and the sample generalized variance control charts were finally utilized in controlling and monitoring future production. In conclusion, the grey relational analysis utilizing Taguchi method is an effective approach for optimizing the die life and wire tensile strength for SUS wire drawing process. 2008 University of Science and Technology Beijing. All rights reserved.展开更多
A dynamic transient flow analysis method considering complex factors such as the cyclic injection and production history in a gas field storage facility was established in view of the limitations of the existing metho...A dynamic transient flow analysis method considering complex factors such as the cyclic injection and production history in a gas field storage facility was established in view of the limitations of the existing methods for transient flow analysis and the characteristics of the injection-production operation of strongly heterogeneous gas reservoirs, and the corresponding theoretical charts were drawn. In addition, an injection-production dynamic transient flow analysis model named "three points and two stages" suitable for an underground gas storage(UGS) well with alternate working conditions was proposed. The "three points" refer to three time points during cyclic injection and production, namely, the starting point of gas injection for UGS construction, the beginning and ending points of the injection-production analysis stage;and the "two stages" refer to historical flow stage and injection-production analysis stage. The study shows that the dimensionless pseudo-pressure and dimensionless pseudo-pressure integral curves of UGS well flex downward in the early stage of the injection and production process, and the dimensionless pseudo-pressure integral derivative curve is convex during the gas production period and concave during the gas injection period, and the curves under different flow histories have atypical features. The new method present in this paper can analyze transient flow of UGS accurately. The application of this method to typical wells in Hutubi gas storage shows that the new method can fit the pressure history accurately, and obtain reliable parameters and results.展开更多
Statistical Quality Control （SQC） is used to analyze and monitor quality characteristic measurements of normal neonatal weight in a maternity clinic in Banjarmasin in this paper. The objective of this study is to as...Statistical Quality Control （SQC） is used to analyze and monitor quality characteristic measurements of normal neonatal weight in a maternity clinic in Banjarmasin in this paper. The objective of this study is to assist medical practitioners in observing pregnant women to deliver their babies with normal weight. It is also assumed that pregnant women who delivered their babies in the clinic have been monitored during their nine-month pregnancy. Thus, they can manage their own pregnancy to deliver normal weight babies. The use of Statistical Process Control （SPC） tools, such as frequency histogram, probability plot, and the implementation of Shewhart, R, and S control charts as primary techniques, are presented to display the monitoring aspects of the process. In addition, Process Capability Analysis （PCA） is performed to ensure that the process outcomes are capable of meeting certain requirements or specifications. The Process Capability Ratio （PCR） for the process is also presented. This analysis is an essential part of an overall quality improvement program.展开更多
This study describes the vowel system of EkeGusii(“Bantu E.42”)(Guthrie,1948)in an acoustic phonetics perspective using oral data got from purposively sampled subjects:four adult males,four adult females and four ch...This study describes the vowel system of EkeGusii(“Bantu E.42”)(Guthrie,1948)in an acoustic phonetics perspective using oral data got from purposively sampled subjects:four adult males,four adult females and four children(two boys and two girls all 8 years old)equally from the two dialects of EkeGusii(EkeMaate and EkeRogoro Dialects).In order to capture the distribution characteristics of the vowel acoustic concentration,the group frequency means are normalized using Lobanov’s(1971)algorithm.Two viewpoints are the subjects of analysis in EkeGusii vowels:(a)acoustic vowel space as projected by the intersection of F2 vs.F1 or quadrilateral,and(b)spatial features of high,low,front and back.These qualities are mainly influenced by the physiology of speakers and social variability as occasioned by gender,age and dialect.The results indicate that children have no gender difference in formants,and have the highest frequencies for all formants,followed by adult females and then adult males.Furthermore,acoustic vowel space and spatial features are affected by gender,age,and dialect.A vowel pattern,replicated by all informants,is realized in the dispersion of the vowels within the chart influenced by gender and age.This study found out that EkeGusii seems to adopt a seven-vowel system of/i eɛaɔo u/with a length contrast.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
To detect and estimate a shift in either the mean and the deviation or both for the preliminary analysis, the statistical process control (SPC) tool, the control chart based on the likelihood ratio test (LRT), is the ...To detect and estimate a shift in either the mean and the deviation or both for the preliminary analysis, the statistical process control (SPC) tool, the control chart based on the likelihood ratio test (LRT), is the most popular method. Sullivan and woodall pointed out the test statistic lrt(n1, n2) is approximately distributed as x2(2) as the sample size n,n1 and n2 are very large, and the value of n1 = 2,3,..., n - 2 and that of n2 = n - n1. So it is inevitable that n1 or n2 is not large. In this paper the limit distribution of lrt(n1, n2) for fixed n1 or n2 is figured out, and the exactly analytic formulae for evaluating the expectation and the variance of the limit distribution are also obtained. In addition, the properties of the standardized likelihood ratio statistic slr(n1, n) are discussed in this paper. Although slr(n1, n) contains the most important information, slr(i, n)(i≠n1) also contains lots of information. The cumulative sum (CUSUM) control chart can obtain more information in this condition. So we propose two CUSUM control charts based on the likelihood ratio statistics for the preliminary analysis on the individual observations. One focuses on detecting the shifts in location in the historical data and the other is more general in detecting a shift in either the location and the scale or both. Moreover, the simulated results show that the proposed two control charts are, respectively, superior to their competitors not only in the detection of the sustained shifts but also in the detection of some other out-of-control situations considered in this paper.展开更多
文摘This paper analyzes the effect of subgroup size on the x-bar chart characteristics using sample influx (SIF) into forensic science laboratory (FSL). The characteristics studied include changes in out-or-control points (OCP), upper control limit UCLx, and zonal demarcations. Multi-rules were used to identify the number of out-of-control-points, Nocp as violations using five control chart rules applied separately. A sensitivity analysis on the Nocp was applied for subgroup size, k, and number of sigma above the mean value to determine the upper control limit, UCLx. A computer code was implemented using a FORTRAN code to create x-bar control-charts and capture OCP and other control-chart characteristics with increasing k from 2 to 25. For each value of k, a complete series of average values, Q(p), of specific length, Nsg, was created from which statistical analysis was conducted and compared to the original SIF data, S(t). The variation of number of out-of-control points or violations, Nocp, for different control-charts rules with increasing k was determined to follow a decaying exponential function, Nocp = Ae–α, for which, the goodness of fit was established, and the R2 value approached unity for Rule #4 and #5 only. The goodness of fit was established to be the new criteria for rational subgroup-size range, for Rules #5 and #4 only, which involve a count of 6 consecutive points decreasing and 8 consecutive points above the selected control limit (σ/3 above the grand mean), respectively. Using this criterion, the rational subgroup range was established to be 4 ≤ k ≤ 20 for the two x-bar control chart rules.
文摘Fast depletion of fossil fuels with its resources already passed its mid depletion region and the pollution levels already reached unsafe levels which make it utmost necessity to search for alternative fuels to meet sustainable energy demand with minimum environmental impact. Among alternative fuels, hydrogen is considered as the near future, long term renewable, sustainable and non-polluting fuel. In the present paper, hydrogen fueled internal combustion engine fundamentals highlighted and presented relating to hydrogen combustion properties. A Mat lab programmed hydrogen temperature-entropy-energy chart is developed and presented for fresh charge and products of combustion at different excess air factors per mole combustion gases. The chart, then, used to represent a SI hydrogen-fueled fuel/air cycle analysis, which proved to be valuable design tool for engine sizing and for prediction of engine performance. Predictions carried out using the hydrogen F/A cycle analysis at different λ show low brake specific fuel consumption and low volume specific power compared with conventional SI engine.
文摘The main purpose of this study was to carry out the DACUM(developing a curriculum)analysis in studying the job functions for digital media designers in Taiwan,China as a case study.The primary tasks were twofold:(A)Study the DACUM Occupational Analysis'connotation and(B)Investigate the outputs of the DACUM Occupational Analysis and establish a job function profile for digital media designers.The research method included(a)Literature Review,to review and discuss the connotation of DACUM Occupational Analysis and(b)Comparative Study,in which a variety of charts of the occupational analysis obtained from the Literature Review were compared to reach conclusions.In summary,various DACUM charts obtained from literature reviews on digital media design jobs appeared significantly different in contents of the charts.Therefore,in any future and consecutive DACUM Occupational Analysis,exiting DACUM Charts could be referenced as the starting point for the DACUM process;then the parameters such as the number of facilitators,panelists,number of tasks,job function duties,personal traits,tools and attributes,etc.should be reviewed and optimized depending on the actual requirement,local development,cultural background,local training and educational levels,etc..Hopefully the case study in establishing the job function descriptions for digital media designers in Taiwan,China presented in the Conclusion Section of this report has demonstrated this process satisfactorily.
文摘In the stainless steel 304 （SUS 304） wire drawing process, optimizing the die life and wire tensile strength, which are the larger-the-better quality characteristics （QCH） types, is of main interest. Three control factors, involving reduction ratio, lubricant temperature, and drawing speed, were investigated utilizing L9（34） orthogonal array （OA）. The grey relational analysis was conducted for the normalized signal-to-noise （S/N） ratios. The ordinal value of the grey grade was then used to decide optimal factor levels. The anticipated improvements in die life and wire tensile strength were estimated 25.31 h and 22.50 kg/mm2, respectively. To decide the significant factor which had effect on each QCH and predict the average value of each QCH, analysis of variance （ANOVA） was performed for S/N ratio and QCH. Confirmation experiments were then conducted, where a good overlap was noticed between the predicted and confirnation intervals for each QCH. The Hotelling T2 and the sample generalized variance control charts were finally utilized in controlling and monitoring future production. In conclusion, the grey relational analysis utilizing Taguchi method is an effective approach for optimizing the die life and wire tensile strength for SUS wire drawing process. 2008 University of Science and Technology Beijing. All rights reserved.
基金Supported by the CNPC Major Scientific and Technological Project(2019B-3204)PetroChina Major Scientific and Technological Project(kt2020-16-01)。
文摘A dynamic transient flow analysis method considering complex factors such as the cyclic injection and production history in a gas field storage facility was established in view of the limitations of the existing methods for transient flow analysis and the characteristics of the injection-production operation of strongly heterogeneous gas reservoirs, and the corresponding theoretical charts were drawn. In addition, an injection-production dynamic transient flow analysis model named "three points and two stages" suitable for an underground gas storage(UGS) well with alternate working conditions was proposed. The "three points" refer to three time points during cyclic injection and production, namely, the starting point of gas injection for UGS construction, the beginning and ending points of the injection-production analysis stage;and the "two stages" refer to historical flow stage and injection-production analysis stage. The study shows that the dimensionless pseudo-pressure and dimensionless pseudo-pressure integral curves of UGS well flex downward in the early stage of the injection and production process, and the dimensionless pseudo-pressure integral derivative curve is convex during the gas production period and concave during the gas injection period, and the curves under different flow histories have atypical features. The new method present in this paper can analyze transient flow of UGS accurately. The application of this method to typical wells in Hutubi gas storage shows that the new method can fit the pressure history accurately, and obtain reliable parameters and results.
文摘Statistical Quality Control （SQC） is used to analyze and monitor quality characteristic measurements of normal neonatal weight in a maternity clinic in Banjarmasin in this paper. The objective of this study is to assist medical practitioners in observing pregnant women to deliver their babies with normal weight. It is also assumed that pregnant women who delivered their babies in the clinic have been monitored during their nine-month pregnancy. Thus, they can manage their own pregnancy to deliver normal weight babies. The use of Statistical Process Control （SPC） tools, such as frequency histogram, probability plot, and the implementation of Shewhart, R, and S control charts as primary techniques, are presented to display the monitoring aspects of the process. In addition, Process Capability Analysis （PCA） is performed to ensure that the process outcomes are capable of meeting certain requirements or specifications. The Process Capability Ratio （PCR） for the process is also presented. This analysis is an essential part of an overall quality improvement program.
文摘This study describes the vowel system of EkeGusii(“Bantu E.42”)(Guthrie,1948)in an acoustic phonetics perspective using oral data got from purposively sampled subjects:four adult males,four adult females and four children(two boys and two girls all 8 years old)equally from the two dialects of EkeGusii(EkeMaate and EkeRogoro Dialects).In order to capture the distribution characteristics of the vowel acoustic concentration,the group frequency means are normalized using Lobanov’s(1971)algorithm.Two viewpoints are the subjects of analysis in EkeGusii vowels:(a)acoustic vowel space as projected by the intersection of F2 vs.F1 or quadrilateral,and(b)spatial features of high,low,front and back.These qualities are mainly influenced by the physiology of speakers and social variability as occasioned by gender,age and dialect.The results indicate that children have no gender difference in formants,and have the highest frequencies for all formants,followed by adult females and then adult males.Furthermore,acoustic vowel space and spatial features are affected by gender,age,and dialect.A vowel pattern,replicated by all informants,is realized in the dispersion of the vowels within the chart influenced by gender and age.This study found out that EkeGusii seems to adopt a seven-vowel system of/i eɛaɔo u/with a length contrast.
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.
基金This work was supported by the Natural Science Foundation of Tianjin (Grant No. 033603111).
文摘To detect and estimate a shift in either the mean and the deviation or both for the preliminary analysis, the statistical process control (SPC) tool, the control chart based on the likelihood ratio test (LRT), is the most popular method. Sullivan and woodall pointed out the test statistic lrt(n1, n2) is approximately distributed as x2(2) as the sample size n,n1 and n2 are very large, and the value of n1 = 2,3,..., n - 2 and that of n2 = n - n1. So it is inevitable that n1 or n2 is not large. In this paper the limit distribution of lrt(n1, n2) for fixed n1 or n2 is figured out, and the exactly analytic formulae for evaluating the expectation and the variance of the limit distribution are also obtained. In addition, the properties of the standardized likelihood ratio statistic slr(n1, n) are discussed in this paper. Although slr(n1, n) contains the most important information, slr(i, n)(i≠n1) also contains lots of information. The cumulative sum (CUSUM) control chart can obtain more information in this condition. So we propose two CUSUM control charts based on the likelihood ratio statistics for the preliminary analysis on the individual observations. One focuses on detecting the shifts in location in the historical data and the other is more general in detecting a shift in either the location and the scale or both. Moreover, the simulated results show that the proposed two control charts are, respectively, superior to their competitors not only in the detection of the sustained shifts but also in the detection of some other out-of-control situations considered in this paper.
