Quality control(QC)is an essential procedure in scatterometer wind retrieval,which is used to distinguish good-quality data from poor-quality wind vector cells(WVCs)for the sake of wind applications.The current wind p...Quality control(QC)is an essential procedure in scatterometer wind retrieval,which is used to distinguish good-quality data from poor-quality wind vector cells(WVCs)for the sake of wind applications.The current wind processor of the China-France Oceanography Satellite(CFOSAT)scatterometer(CSCAT)adopts a maximum likelihood estimator(MLE)-based QC method to filter WVCs affected by geophysical noise,such as rainfall and wind variability.As the first Ku-band rotating fan-beam scatterometer,CSCAT can acquire up to 16 observations over a single WVC,giving abundant information with diverse incidence/azimuth angles,as such its MLE statistical characteristics may be different from the previous scatterometers.In this study,several QC indicators,including MLE,its spatially averaged value(MLE_(m)),and the singularity exponents(SE),are analyzed using the collocated Global Precipitation Mission rainfall data as well as buoy data,to compare their sensitivity to rainfall and wind quality.The results show that wind error characteristics of CSCAT under different QC methods are similar to those of other Ku-band scatterometers,i.e.,SE is more suitable than other parameters for the wind QC at outer-swath and nadir regions,while MLE_(m) is the best QC indicator for the sweet region WVCs.Specifically,SE is much more favorable than others at high wind speeds.By combining different indicators,an improved QC method is developed for CSCAT.The validation with the collocated buoy data shows that it accepts more WVCs,and in turn,improves the quality control of CSCAT wind data.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 objective of this study was to assess the quality of randomized controlled trials（RCTs） on pharmaceutical care for asthma tic patients conducted by pharmacists in China's Mainland, to identify the problems i...The objective of this study was to assess the quality of randomized controlled trials（RCTs） on pharmaceutical care for asthma tic patients conducted by pharmacists in China's Mainland, to identify the problems in current studies, and to provide some references for further studies. The China National Knowledge Infrastructure（CNKI）, Wanfang Database, and VIP Database were searched for randomized controlled trials on pharmaceutical care for asthma tic patients, and only those studies undertaken by pharmacists were included. Information about the study design and reporting of selected studies was extracted and collected to systematically analyze these studies. Meanwhile, the Cochrane Collaboration＇s tool for assessing risk of bias was used to assess potential biases related to these studies. Ultimately, 14 articles were included in this study. No study determined the sample size in a scientific way. No article reported a scientific and detailed method of random sequence generation or allocation concealment. Two（14.3%） studies claimed to have implemented a double-blinding and a single-blinding respectively, but neither of them reported any details about how they performed the blinding. No study employed a blinding of outcome assessment. Five（35.7%） studies either stated statistical methods incompletely or used them incorrectly. One（7.1%） study reported an attrition without employing an intention-to-treat analysis. All studies reported eligibility criteria for participants to some extent, and all these criteria involved diagnosis of asthma, but only four（28.6%） of them reported patients＇ ages and three（21.4%） described the severity and the stage of asthma. Nine（64.3%） reported baseline data in the text rather than in a table, and 13（92.9%） involved comparisons between groups with significance tests either explicitly or implicitly. No report made a distinction between primary and secondary outcomes. Two（14.3%） mentioned informed consent of subjects, while no article reported ethical approval. ＂Unclear risk＂ made up the highest percentage of the studies analyzed according to the risk of bias assessment by the Cochrane Collaboration＇s tool. Our study demonstrates that the quality of RCTs on pharmaceutical care for asthma tic patients conducted by Chinese pharmacists is suboptimal, especially with regards to study design and reporti ng.展开更多
The growing popularity of Internet applications and services has rendered high subjective video quality crucial to the user experience. Increasing needs for better video resolution and faster transmission bandwidths p...The growing popularity of Internet applications and services has rendered high subjective video quality crucial to the user experience. Increasing needs for better video resolution and faster transmission bandwidths present challenges to the goal of achieving balance between video quality and coding cost. In this paper, we propose a Perceptive Variable Bit-Rate Control （PVBRC） framework for the state-of-the-art video coding standard High-Efficiency Video Coding （HEVC）/H.265. PVBRC allocates a bit-rate to a picture while taking a Comprehensive Picture Quality Assessment （CPQA） model and perceptive target bit-rate allocation into consideration. The CPQA model calculates the objective and perceptive quality of both source and reconstructed pictures by referring to the human vision system. The coding bit-rate is then dynamically allocated by the result of the CPQA model according to differences in picture content. In PVBRC, the quantization parameter for current picture encoding is updated by an effective fuzzy logical controller to satisfy the transmission requirements of the Internet of Things. Experimental results show that the proposed PVBRC can achieve average bit savings by 11.49% when compared with constant bit-rate control under the same objective and subjective video quality.展开更多
基金The National Key Research and Development Program of China under contract Nos 2022YFC3104900 and 2022YFC3104902.
文摘Quality control(QC)is an essential procedure in scatterometer wind retrieval,which is used to distinguish good-quality data from poor-quality wind vector cells(WVCs)for the sake of wind applications.The current wind processor of the China-France Oceanography Satellite(CFOSAT)scatterometer(CSCAT)adopts a maximum likelihood estimator(MLE)-based QC method to filter WVCs affected by geophysical noise,such as rainfall and wind variability.As the first Ku-band rotating fan-beam scatterometer,CSCAT can acquire up to 16 observations over a single WVC,giving abundant information with diverse incidence/azimuth angles,as such its MLE statistical characteristics may be different from the previous scatterometers.In this study,several QC indicators,including MLE,its spatially averaged value(MLE_(m)),and the singularity exponents(SE),are analyzed using the collocated Global Precipitation Mission rainfall data as well as buoy data,to compare their sensitivity to rainfall and wind quality.The results show that wind error characteristics of CSCAT under different QC methods are similar to those of other Ku-band scatterometers,i.e.,SE is more suitable than other parameters for the wind QC at outer-swath and nadir regions,while MLE_(m) is the best QC indicator for the sweet region WVCs.Specifically,SE is much more favorable than others at high wind speeds.By combining different indicators,an improved QC method is developed for CSCAT.The validation with the collocated buoy data shows that it accepts more WVCs,and in turn,improves the quality control of CSCAT wind data.
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.
文摘The objective of this study was to assess the quality of randomized controlled trials（RCTs） on pharmaceutical care for asthma tic patients conducted by pharmacists in China's Mainland, to identify the problems in current studies, and to provide some references for further studies. The China National Knowledge Infrastructure（CNKI）, Wanfang Database, and VIP Database were searched for randomized controlled trials on pharmaceutical care for asthma tic patients, and only those studies undertaken by pharmacists were included. Information about the study design and reporting of selected studies was extracted and collected to systematically analyze these studies. Meanwhile, the Cochrane Collaboration＇s tool for assessing risk of bias was used to assess potential biases related to these studies. Ultimately, 14 articles were included in this study. No study determined the sample size in a scientific way. No article reported a scientific and detailed method of random sequence generation or allocation concealment. Two（14.3%） studies claimed to have implemented a double-blinding and a single-blinding respectively, but neither of them reported any details about how they performed the blinding. No study employed a blinding of outcome assessment. Five（35.7%） studies either stated statistical methods incompletely or used them incorrectly. One（7.1%） study reported an attrition without employing an intention-to-treat analysis. All studies reported eligibility criteria for participants to some extent, and all these criteria involved diagnosis of asthma, but only four（28.6%） of them reported patients＇ ages and three（21.4%） described the severity and the stage of asthma. Nine（64.3%） reported baseline data in the text rather than in a table, and 13（92.9%） involved comparisons between groups with significance tests either explicitly or implicitly. No report made a distinction between primary and secondary outcomes. Two（14.3%） mentioned informed consent of subjects, while no article reported ethical approval. ＂Unclear risk＂ made up the highest percentage of the studies analyzed according to the risk of bias assessment by the Cochrane Collaboration＇s tool. Our study demonstrates that the quality of RCTs on pharmaceutical care for asthma tic patients conducted by Chinese pharmacists is suboptimal, especially with regards to study design and reporti ng.
基金supported by Foundation of Science and Technology Department of Sichuan Province (Nos. 2017JY0007 and 2017HH0075)
文摘The growing popularity of Internet applications and services has rendered high subjective video quality crucial to the user experience. Increasing needs for better video resolution and faster transmission bandwidths present challenges to the goal of achieving balance between video quality and coding cost. In this paper, we propose a Perceptive Variable Bit-Rate Control （PVBRC） framework for the state-of-the-art video coding standard High-Efficiency Video Coding （HEVC）/H.265. PVBRC allocates a bit-rate to a picture while taking a Comprehensive Picture Quality Assessment （CPQA） model and perceptive target bit-rate allocation into consideration. The CPQA model calculates the objective and perceptive quality of both source and reconstructed pictures by referring to the human vision system. The coding bit-rate is then dynamically allocated by the result of the CPQA model according to differences in picture content. In PVBRC, the quantization parameter for current picture encoding is updated by an effective fuzzy logical controller to satisfy the transmission requirements of the Internet of Things. Experimental results show that the proposed PVBRC can achieve average bit savings by 11.49% when compared with constant bit-rate control under the same objective and subjective video quality.
