1 Introduction It has been noticed that salts link the Earth’s spheres(Zheng,2007),and rich information must have been recorded by salts on the geological processes they involved in.Salts have been found on Mars,Euro...1 Introduction It has been noticed that salts link the Earth’s spheres(Zheng,2007),and rich information must have been recorded by salts on the geological processes they involved in.Salts have been found on Mars,Europa,Enceladus,and salts might be common on planets(Zheng et al.,2013).Thus salts can be potential indicators for studying the geological history of planets.From the beginning of the 21st century,much new展开更多
In recent years, there has been mounting interest i n measuring process performance in manufacturing industry. Based on analyzing the process capability indices, a production department can trace and improve a poor pr...In recent years, there has been mounting interest i n measuring process performance in manufacturing industry. Based on analyzing the process capability indices, a production department can trace and improve a poor process to enhance quality levels and satisfy customers. The process capabilit y analysis can also serve as an important reference for making decisions for imp roving the global quality of all products. Since C p and C pk are failed to account for process centering, the index C pm is developed. The index C pm takes the process centering into consideration and is su itable for the processes with nominal-the-best type. There are other indices l ike C pu and C pl, and those indices are used for unilateral s pecification processes. Chou (1994) developed a procedure using estimators of C p, C pu and C pl for practitioners to determine whether two p rocesses are equal capability or not. For bilateral specifications processes, i ndex C p is failed to measure process yield and process centering. Thus, th e index C pm is used to develop a similar procedure for practitioners t o determine whether two processes are equal capability or not. The decisions mad e using the procedure to select the better supplier are, of course, more reliabl e.展开更多
Process Capability Analysis (PCA) is a powerful too l to assess the ability of a process for manufacturing product that meets specific ations. The larger process capability index implies the higher process yield, a nd...Process Capability Analysis (PCA) is a powerful too l to assess the ability of a process for manufacturing product that meets specific ations. The larger process capability index implies the higher process yield, a nd the larger process capability index also indicates the lower process expected loss. Chen et al. (2001) has applied indices C pu, C pl, and C pk for evaluating the process capability for a multi-process product wi th smaller-the-better, larger-the-better, and nominal-the-best specificati ons respectively. However, C pk cannot reasonably reflect the process expected loss. In this paper, index C pn is selected to replace C pk. Indices C pu, C pl, and C pn are used to evalu ate the entire process capability for a multi-process product with smaller-the -better, larger-the-better, and nominal-the-best specifications respectivel y. An integrated process capability index for a multi-process product is propo sed. The relationship between process capability index and the process yield is introduced. A multi-process capability analysis chart (MPCAC), reasonably rev ealing the status of process capability for the entire product, is constructed f or practical application. An evaluating procedure of the process capability for the entire product is also provided.展开更多
Two simple, easy and correct process capability indices are presented in this paper which is based on the investigation of the actual management situation of manufacture process in the medium or small enterprise of ou...Two simple, easy and correct process capability indices are presented in this paper which is based on the investigation of the actual management situation of manufacture process in the medium or small enterprise of our country, and the applicability analysis for the evaluating methods of process capability. The coincidental degree of distribution center between the product quality and the spec tolerance is considered in the method, and the parameter of actual standard deviation is used. So the indices have higher accuracy and reflect the essential aspect of the problem.展开更多
From a regulatory perspective,drug quality consistency evaluation must concern different processes used for the same drug.In this study,an assessment strategy based on quality by design(QbD)was developed for populatio...From a regulatory perspective,drug quality consistency evaluation must concern different processes used for the same drug.In this study,an assessment strategy based on quality by design(QbD)was developed for population pharmaceutical quality evaluation.A descriptive analysis method based on QbD concept was first established to characterize the process by critical evaluation attributes(CEAs).Then quantitative analysis method based on an improved statistical process control(SPC)method was established to investigate the process indicators(PIs)in the process population,such as mean distribution,batch-to-batch difference and abnormal quality probability.After that rules for risk assessment were established based on the SPC limitations and parameters.Both the SPC parameters of the CEAs and the risk of PIs were visualized according to the interaction test results to obtain a better understanding of the population pharmaceutical quality.Finally,an assessment strategy was built and applied to generic drug consistency assessment,process risk assessment and quality trend tracking.The strategy demonstrated in this study could help reveal quality consistency from the perspective of process control and process risk,and further show the recent development status of domestic pharmaceutical production processes.In addition,a process risk assessment and population quality trend tracking provide databased information for approval.Not only can this information serve as a further basis for decisionmaking by the regulatory authority regarding early warnings,but it can also reduce some avoidable adverse reactions.With continuous addition of data,dynamic population pharmaceutical quality is meaningful for emergencies and decision-making regarding drug regulation.展开更多
The effect of free ammonia on volatile fatty acid (VFA) accumulation and process instability was studied using a lab-scale anaerobic digester fed by two typical bio-wastes: fruit and vegetable waste (FVW) and foo...The effect of free ammonia on volatile fatty acid (VFA) accumulation and process instability was studied using a lab-scale anaerobic digester fed by two typical bio-wastes: fruit and vegetable waste (FVW) and food waste (FW) at 35℃ with an organic loading rate (OLR) of 3.0 kg VS/(m3-day). The inhibitory effects of free ammonia on methanogenesis were observed due to the low C/N ratio of each substrate (15.6 and 17.2, respectively). A high concentration of free ammonia inhibited methanogenesis resulting in the accumulation of VFAs and a low methane yield. In the inhibited state, acetate accumulated more quickly than propionate and was the main type of accumulated VFA. The co-accumulation of ammonia and VFAs led to an "inhibited steady state" and the ammonia was the main inhibitory substance that triggered the process perturbation. By statistical significance test and VFA fluctuation ratio analysis, the free ammonia inhibition threshold was identified as 45 mg/L. Moreover, propionate, iso-butyrate and valerate were determined to be the three most sensitive VFA parameters that were subject to ammonia inhibition.展开更多
文摘1 Introduction It has been noticed that salts link the Earth’s spheres(Zheng,2007),and rich information must have been recorded by salts on the geological processes they involved in.Salts have been found on Mars,Europa,Enceladus,and salts might be common on planets(Zheng et al.,2013).Thus salts can be potential indicators for studying the geological history of planets.From the beginning of the 21st century,much new
文摘In recent years, there has been mounting interest i n measuring process performance in manufacturing industry. Based on analyzing the process capability indices, a production department can trace and improve a poor process to enhance quality levels and satisfy customers. The process capabilit y analysis can also serve as an important reference for making decisions for imp roving the global quality of all products. Since C p and C pk are failed to account for process centering, the index C pm is developed. The index C pm takes the process centering into consideration and is su itable for the processes with nominal-the-best type. There are other indices l ike C pu and C pl, and those indices are used for unilateral s pecification processes. Chou (1994) developed a procedure using estimators of C p, C pu and C pl for practitioners to determine whether two p rocesses are equal capability or not. For bilateral specifications processes, i ndex C p is failed to measure process yield and process centering. Thus, th e index C pm is used to develop a similar procedure for practitioners t o determine whether two processes are equal capability or not. The decisions mad e using the procedure to select the better supplier are, of course, more reliabl e.
文摘Process Capability Analysis (PCA) is a powerful too l to assess the ability of a process for manufacturing product that meets specific ations. The larger process capability index implies the higher process yield, a nd the larger process capability index also indicates the lower process expected loss. Chen et al. (2001) has applied indices C pu, C pl, and C pk for evaluating the process capability for a multi-process product wi th smaller-the-better, larger-the-better, and nominal-the-best specificati ons respectively. However, C pk cannot reasonably reflect the process expected loss. In this paper, index C pn is selected to replace C pk. Indices C pu, C pl, and C pn are used to evalu ate the entire process capability for a multi-process product with smaller-the -better, larger-the-better, and nominal-the-best specifications respectivel y. An integrated process capability index for a multi-process product is propo sed. The relationship between process capability index and the process yield is introduced. A multi-process capability analysis chart (MPCAC), reasonably rev ealing the status of process capability for the entire product, is constructed f or practical application. An evaluating procedure of the process capability for the entire product is also provided.
基金the Development Foundation of Science and Technology of Shanghai Municipal Commission of Education(97AJ05)
文摘Two simple, easy and correct process capability indices are presented in this paper which is based on the investigation of the actual management situation of manufacture process in the medium or small enterprise of our country, and the applicability analysis for the evaluating methods of process capability. The coincidental degree of distribution center between the product quality and the spec tolerance is considered in the method, and the parameter of actual standard deviation is used. So the indices have higher accuracy and reflect the essential aspect of the problem.
基金The National Major Scientific and Technological Special Project for‘Significant New Drugs Development’(Grant No.:2017ZX0901001-007)provides support for this study.
文摘From a regulatory perspective,drug quality consistency evaluation must concern different processes used for the same drug.In this study,an assessment strategy based on quality by design(QbD)was developed for population pharmaceutical quality evaluation.A descriptive analysis method based on QbD concept was first established to characterize the process by critical evaluation attributes(CEAs).Then quantitative analysis method based on an improved statistical process control(SPC)method was established to investigate the process indicators(PIs)in the process population,such as mean distribution,batch-to-batch difference and abnormal quality probability.After that rules for risk assessment were established based on the SPC limitations and parameters.Both the SPC parameters of the CEAs and the risk of PIs were visualized according to the interaction test results to obtain a better understanding of the population pharmaceutical quality.Finally,an assessment strategy was built and applied to generic drug consistency assessment,process risk assessment and quality trend tracking.The strategy demonstrated in this study could help reveal quality consistency from the perspective of process control and process risk,and further show the recent development status of domestic pharmaceutical production processes.In addition,a process risk assessment and population quality trend tracking provide databased information for approval.Not only can this information serve as a further basis for decisionmaking by the regulatory authority regarding early warnings,but it can also reduce some avoidable adverse reactions.With continuous addition of data,dynamic population pharmaceutical quality is meaningful for emergencies and decision-making regarding drug regulation.
基金supported by the Ministry of Science and Technology of China(Nos.2008BADC4B18,2014BAC27B01)
文摘The effect of free ammonia on volatile fatty acid (VFA) accumulation and process instability was studied using a lab-scale anaerobic digester fed by two typical bio-wastes: fruit and vegetable waste (FVW) and food waste (FW) at 35℃ with an organic loading rate (OLR) of 3.0 kg VS/(m3-day). The inhibitory effects of free ammonia on methanogenesis were observed due to the low C/N ratio of each substrate (15.6 and 17.2, respectively). A high concentration of free ammonia inhibited methanogenesis resulting in the accumulation of VFAs and a low methane yield. In the inhibited state, acetate accumulated more quickly than propionate and was the main type of accumulated VFA. The co-accumulation of ammonia and VFAs led to an "inhibited steady state" and the ammonia was the main inhibitory substance that triggered the process perturbation. By statistical significance test and VFA fluctuation ratio analysis, the free ammonia inhibition threshold was identified as 45 mg/L. Moreover, propionate, iso-butyrate and valerate were determined to be the three most sensitive VFA parameters that were subject to ammonia inhibition.