AIM: To determine the correlation of Adjusted Blood Requirement Index (ABRI) with the 7th day outcome in patients presenting with acute variceal bleeding.METHODS: All patients presenting with acute variceal hemorr...AIM: To determine the correlation of Adjusted Blood Requirement Index (ABRI) with the 7th day outcome in patients presenting with acute variceal bleeding.METHODS: All patients presenting with acute variceal hemorrhage (AVH) were included. Patients with previous band ligation, sclerotherapy, gastrointestinal or hepatic malignancies were excluded. Patients were managed as per standard protocol for AVH with terlipressin and band ligation. ABRI scores were calculated using the formula outcome of alive or expired up to the 7th day after treatment. The correlation between ABRI and mortality was estimated and a receiver operative characteristic (ROC) curve was plotted.RESULTS: A total of 113 patients (76 male; 37 female) were included. On assessment, 18 were in Child's Pugh Class A, 82 in Class B and 13 were in Class C. The median number of blood units transfused ± inter-quartile range was 3.0 ± 2.0. The median ± inter-quartile range for ABRI was 1.3 ± 1.1. The ROC curve of ABRI for expiry showed a significantly large area of 0.848 (P 〈 0.0001; 95% CI: 0.75-0.95). A significant correlation of log transformation of ABRI with an outcome of mortality was present (P 〈 0.0001).展开更多
Aiming at a comprehensive assessment of energy-saving retrofitting effect on existing buildings,a calculation method is developed to adjust energy-saving quantity in standard condition for comparison under the same co...Aiming at a comprehensive assessment of energy-saving retrofitting effect on existing buildings,a calculation method is developed to adjust energy-saving quantity in standard condition for comparison under the same conditions. A mathematical model,method theory and calculation steps are given. Error analysis results show that this method can be applied accurately to practical engineering projects. In a case study of energy-saving quantity assessment before and after retrofitting on a certain hospital in Shanghai,with energy simulation software TRNSYS,detailed application of this method is introduced and analyzed. The method is applied to the case of energy-saving quantity assessment to a hospital in Shanghai before and after retrofitting with the energy simulation software TRNSYS.展开更多
Based on analysis of the present hydraulic impactor, a new hydraulic impactor with pressure feedback control was developed, whose structure and operation principle were introduced. The results show that the pressure o...Based on analysis of the present hydraulic impactor, a new hydraulic impactor with pressure feedback control was developed, whose structure and operation principle were introduced. The results show that the pressure of the impact system can be adjusted steplessly to change the impact energy of the impactor steplessly. By adjusting the oil flow of supply pump steplessly, the impact frequency will also be changed steplessly. So the impact energy and frequency of the new impactor can be adjusted independently and steplessly. In order to decrease the energy loss, a new kind of sleeve valve has been designed, which has features of little leakage, little pressure loss and low energy cost. The new type hydraulic impactor can be operated under various conditions with decreased energy consumption and improved operation efficiency.展开更多
The General Customs Administration issued a circular statingthat,based upon a decision of the State Council,in 1997 someimport and export tariff rates would be adjusted.The major con-tents of the circular are the adju...The General Customs Administration issued a circular statingthat,based upon a decision of the State Council,in 1997 someimport and export tariff rates would be adjusted.The major con-tents of the circular are the adjustment of the import tariff rates of 4tariff lines of commodities and items under 124 tariff lines;theelimination of the export tariffs for 14 tariff lines of commodities,addition of export tariff rates for 2 kinds of precious metals andimposition of provisional export tariff rates for 4 kinds of corn-展开更多
The increasing penetration of wind power presents many technical challenges to power system operations. An important challenge is the need of voltage control to maintain the terminal voltage of a wind plant to make it...The increasing penetration of wind power presents many technical challenges to power system operations. An important challenge is the need of voltage control to maintain the terminal voltage of a wind plant to make it a PV bus like conventional generators with excitation control. In the previous work for controlling wind plant, especially the Doubly Fed Induction Generator (DFIG) system, the proportional-integral (PI) controllers are popularly applied. These approaches usually need to tune the PI controllers to obtain control gains as a tradeoff or compromise among various operating conditions. In this paper, a new voltage control approach based on a different philosophy is presented. In the proposed approach, the PI control gains for the DFIG system are dynamically adjusted based on the dynamic, continuous sensitivity which essentially indicates the dynamic relationship between the change of control gains and the desired output voltage. Hence, this control approach does not require any good estimation of fixed control gains because it has the self-learning mechanism via the dynamic sensitivity. This also gives the plug-and-play feature of DFIG controllers to make it promising in utility practices. Simulation results verify that the proposed approach performs as expected under various operating conditions.展开更多
The pavement strength is very important for the evaluation of backlog maintenance. The current trend in many developing countries used pavement conditions index-PCI in estimating maintenance costs. The PCI can only ju...The pavement strength is very important for the evaluation of backlog maintenance. The current trend in many developing countries used pavement conditions index-PCI in estimating maintenance costs. The PCI can only justify periodic and routine recurrent maintenance. The condition strength is rarely determined in a flexible pavement creating an opportunity for back long maintenance. This paper reports the study conducted to develop and improve the algorithm for estimating the adjusted structure number to estimate the remaining thickness of the flexible pavement. The analysis of eight ways of computing structure numbers from FWD data ware analyzed and found that the improvement of the HDM 3 - 4 models can influence the usefulness of data collected from road asset management in Tanzania. The algorithm for estimating structural numbers from CBR was improved to compute adjusted structural numbers finally used to estimate the remaining life of the flexible pavement. The analysis of the network of about 6900 km including ST and AM was found that 64.72% were very good, 12% were Good, 10% were fair and 7.84% were poor and 5.4% were very poor.展开更多
Since October 2008,China's social consumption of electricity had,for the first time,grown negatively compared to the same period of the previous year,and in November the negative growth range further expanded. The...Since October 2008,China's social consumption of electricity had,for the first time,grown negatively compared to the same period of the previous year,and in November the negative growth range further expanded. The major pressure faced by the electricity industry has now turned from the contradiction between coal and electricity to electricity quantity. This is undoubtedly a true and new test to electricity enterprises which get used to high growth but are now suffering great losses. The reform of electricity system has already been in great difficulties and now is getting into a more serious situation. In order to help readers improve their knowledge and understanding of the current tough situation faced by the electricity industry and discuss how to alleviate and get through the difficulty resulted from the economic crisis "encountered once every one hundred years" by joint efforts of all parties concerned,a Seminar on Crisis and Countermeasures for Electricity Industry was held on November 20,2008. Here are some extracts from the speeches of four experts.展开更多
The tentative tariff rate for partial import and export products was adjusted since November 1^(st) of 2006.Total 58 imported commodities will be imposed lower tentative
This paper reports the sensitive effect of photoluminescence peak intensity and transmittance affected by B, Al, and N dopants in fluorescent 4H-SiC single crystals. The crystalline type, doping concentration, photolu...This paper reports the sensitive effect of photoluminescence peak intensity and transmittance affected by B, Al, and N dopants in fluorescent 4H-SiC single crystals. The crystalline type, doping concentration, photoluminescence spectra,and transmission spectra were characterized at room temperature. It is found that the doped 4H-SiC single crystal emits a warm white light covering a wide range from 460 nm to 720 nm, and the transmittance increases from ~10% to ~60%with the fluctuation of B, Al, and N ternary dopants. With a parameter of C_(D-A), defined by B, Al, and N concentration, the photoluminescence and transmittance properties can be adjusted by optimal doping regulation.展开更多
This study explored a new model of Prostate Imaging Reporting and Data System(PIRADS)and adjusted prostate-specific antigen density of peripheral zone(aPSADPZ)for predicting the occurrence of prostate cancer(PCa)and c...This study explored a new model of Prostate Imaging Reporting and Data System(PIRADS)and adjusted prostate-specific antigen density of peripheral zone(aPSADPZ)for predicting the occurrence of prostate cancer(PCa)and clinically significant prostate cancer(csPCa).The demographic and clinical characteristics of 853 patients were recorded.Prostate-specific antigen(PSA),PSA density(PSAD),PSAD of peripheral zone(PSADPZ),aPSADPZ,and peripheral zone volume ratio(PZ-ratio)were calculated and subjected to receiver operating characteristic(ROC)curve analysis.The calibration and discrimination abilities of new nomograms were verified with the calibration curve and area under the ROC curve(AUC).The clinical benefits of these models were evaluated by decision curve analysis and clinical impact curves.The AUCs of PSA,PSAD,PSADPZ,aPSADPZ,and PZ-ratio were 0.669,0.762,0.659,0.812,and 0.748 for PCa diagnosis,while 0.713,0.788,0.694,0.828,and 0.735 for csPCa diagnosis,respectively.All nomograms displayed higher net benefit and better overall calibration than the scenarios for predicting the occurrence of PCa or csPCa.The new model significantly improved the diagnostic accuracy of PCa(0.945 vs 0.830,P<0.01)and csPCa(0.937 vs 0.845,P<0.01)compared with the base model.In addition,the number of patients with PCa and csPCa predicted by the new model was in good agreement with the actual number of patients with PCa and csPCa in high-risk threshold.This study demonstrates that aPSADPZ has a higher predictive accuracy for PCa diagnosis than the conventional indicators.Combining aPSADPZ with PIRADS can improve PCa diagnosis and avoid unnecessary biopsies.展开更多
A uniform experimental design(UED)is an extremely used powerful and efficient methodology for designing experiments with high-dimensional inputs,limited resources and unknown underlying models.A UED enjoys the followi...A uniform experimental design(UED)is an extremely used powerful and efficient methodology for designing experiments with high-dimensional inputs,limited resources and unknown underlying models.A UED enjoys the following two significant advantages:(i)It is a robust design,since it does not require to specify a model before experimenters conduct their experiments;and(ii)it provides uniformly scatter design points in the experimental domain,thus it gives a good representation of this domain with fewer experimental trials(runs).Many real-life experiments involve hundreds or thousands of active factors and thus large UEDs are needed.Constructing large UEDs using the existing techniques is an NP-hard problem,an extremely time-consuming heuristic search process and a satisfactory result is not guaranteed.This paper presents a new effective and easy technique,adjusted Gray map technique(AGMT),for constructing(nearly)UEDs with large numbers of four-level factors and runs by converting designs with s two-level factors and n runs to(nearly)UEDs with 2^(t−1)s four-level factors and 2tn runs for any t≥0 using two simple transformation functions.Theoretical justifications for the uniformity of the resulting four-level designs are given,which provide some necessary and/or sufficient conditions for obtaining(nearly)uniform four-level designs.The results show that the AGMT is much easier and better than the existing widely used techniques and it can be effectively used to simply generate new recommended large(nearly)UEDs with four-level factors.展开更多
To improve the precision of estimation and power of testing hypothesis for an unconditional treatment effect in randomized clinical trials with binary outcomes,researchers and regulatory agencies recommend using g com...To improve the precision of estimation and power of testing hypothesis for an unconditional treatment effect in randomized clinical trials with binary outcomes,researchers and regulatory agencies recommend using g computation as a reliable method of covariate adjustment.How-ever,the practical application of g-computation is hindered by the lack of an explicit robust variance formula that can be used for different unconditional treatment effects of interest.To fill this gap,we provide explicit and robust variance estimators for g-computation estimators and demonstrate through simulations that the variance estimators can be reliably applied in practice.展开更多
Compared with organic solar cells(OSCs) adopting conventional architecture,inverted OSCs have offered generally better stability,where Zn O is the most widely used electron transporting layer(ETL) material.For ZnO-bas...Compared with organic solar cells(OSCs) adopting conventional architecture,inverted OSCs have offered generally better stability,where Zn O is the most widely used electron transporting layer(ETL) material.For ZnO-based inverted OSCs,a welltuned interface of organic(active layer)-inorganic(Zn O film) with matched surface energy(γS) is critical for both high performance and high stability.In this work,two typical calixarenes,C4A and Bu C4A,were employed as the tuning agents to adjust this organic-inorganic interface for ZnO-based inverted OSCs.As a result,with PM6:L8-BO as the active layer,significantly promoted power conversion efficiencies(PCEs) from 17.14%(for ZnO) to 18.25%(for ZnO/C4A) and 17.80%(for ZnO/Bu C4A) were achieved.Photodynamic studies indicate that the enhanced performance is due to the faster charge extraction process,the suppressed recombination and more ideal internal electric field in ZnO/calixarene-based devices.In addition,wellmatched interface energy and more ordered molecular aggregation in active layer effectively improved photostability and thermal stability for ZnO/calixarene-based devices.These results indicate that calixarenes could act as effective modifying agents of ZnO to improve inverted OSCs’ performance and stability simultaneously,and likely also stimulate calixarenes’ and other macromolecules’ broader studies in other organic electronic devices.展开更多
The effects of adjusting technological conditions on the phosphorous enrichment of adjusted converter slag were investigated. The results showed that the phosphorus could he effectively enriched to 2CaO · SiO2 an...The effects of adjusting technological conditions on the phosphorous enrichment of adjusted converter slag were investigated. The results showed that the phosphorus could he effectively enriched to 2CaO · SiO2 and 2CaO · SiO2-3CaO· P2O5 solid solution (SS, namely phosphorus-rich phase) to be formed with the decreasing of basicity and cooling rate. Moreover, the morphology of the phosphorus-rich phase changed from granular for the original converter slag with higher basicity to the coexistence of granular shape and rod-like for the adjusted slag with lower basicity. P2 05 content in phosphorus-rich phase exceeded 30° while the hasicity was 1.3 at the cooling rate of 1.0 ℃/min.展开更多
DEA(data envelopment analysis) models can be divided into two groups: Radial DEA and non-radial DEA, and the latter has higher discriminatory power than the former. The range adjusted measure(RAM) is an effective and ...DEA(data envelopment analysis) models can be divided into two groups: Radial DEA and non-radial DEA, and the latter has higher discriminatory power than the former. The range adjusted measure(RAM) is an effective and widely used non-radial DEA approach. However, to the best of our knowledge, there is no literature on the integer-valued super-efficiency RAM-DEA model,especially when undesirable outputs are included. We first propose an integer-valued RAM-DEA mode with undesirable outputs and then extend this model to an integer-valued super-efficiency RAM-DEA model with undesirable outputs. Compared with other DEA models, the two novel models have many advantages: 1) They are non-oriented and non-radial DEA models, which enable decision makers to simultaneously and non-proportionally improve inputs and outputs;2) They can handle integer-valued variables and undesirable outputs, so the results obtained are more reliable;3) The results can be easily obtained as it is based on linear programming;4) The integer-valued super-efficiency RAM-DEA model with undesirable outputs can be used to accurately rank efficient DMUs. The proposed models are applied to evaluate the efficiency of China’s regional transportation systems(RTSs) considering the number of transport accidents(an undesirable output). The results help decision makers improve the performance of inefficient RTSs and analyze the strengths of efficient RTSs.展开更多
The reanalysis datasets (CRA40) have now been developed in China Meteorological Administration. We aim to compare the differences in surface air temperature (SAT) between observational that has been adjusted for urban...The reanalysis datasets (CRA40) have now been developed in China Meteorological Administration. We aim to compare the differences in surface air temperature (SAT) between observational that has been adjusted for urbanization bias and reanalysis data (NCEPV1, NCEPV2, ERA5, CFSR, MERRA, JRA55, 20CRV3 and CRA40) over China's Mainland during 1961–2015. The main results are presented as follows. The correlation and standard deviation between the reanalysis data and observations exhibit highly consistent interannual variability and dispersion, with the interannual SAT variability in JRA55 being closest to the observations for 1961–2015 and that of ERA5 for 1979–2015;the dispersions of 20CRV3 is most consistent with the observations for 1961–2015 and that of NCEPV1 for 1979–2015. Although annual mean SAT of the reanalysis is generally 0–2.0 ℃ lower than the observations, the bias in the SAT climatology of 20CRV3 is the least for 1961–2015 in all reanalysis datasets and that of CRA40 is the least for 1979–2015. The trends of NCEPV1 is closer to the observations than other reanalysis for 1961–2015 and that of 20CRV3 for 1979–2015. The biases in terms of interannual variability, dispersion, climatology, and linear trend are increase with altitude. Overall, in terms of the similarity of multiple measures to the urbanization bias-adjusted observations, JRA55 and CRA40 show the best performances for the periods 1961–2015 and 1979–2015 respectively in reproducing various aspects of climatological and climate change features in China's Mainland.展开更多
文摘AIM: To determine the correlation of Adjusted Blood Requirement Index (ABRI) with the 7th day outcome in patients presenting with acute variceal bleeding.METHODS: All patients presenting with acute variceal hemorrhage (AVH) were included. Patients with previous band ligation, sclerotherapy, gastrointestinal or hepatic malignancies were excluded. Patients were managed as per standard protocol for AVH with terlipressin and band ligation. ABRI scores were calculated using the formula outcome of alive or expired up to the 7th day after treatment. The correlation between ABRI and mortality was estimated and a receiver operative characteristic (ROC) curve was plotted.RESULTS: A total of 113 patients (76 male; 37 female) were included. On assessment, 18 were in Child's Pugh Class A, 82 in Class B and 13 were in Class C. The median number of blood units transfused ± inter-quartile range was 3.0 ± 2.0. The median ± inter-quartile range for ABRI was 1.3 ± 1.1. The ROC curve of ABRI for expiry showed a significantly large area of 0.848 (P 〈 0.0001; 95% CI: 0.75-0.95). A significant correlation of log transformation of ABRI with an outcome of mortality was present (P 〈 0.0001).
基金Project(2006BAJ03A10) supported by the National Key Technologies R & D Program of China
文摘Aiming at a comprehensive assessment of energy-saving retrofitting effect on existing buildings,a calculation method is developed to adjust energy-saving quantity in standard condition for comparison under the same conditions. A mathematical model,method theory and calculation steps are given. Error analysis results show that this method can be applied accurately to practical engineering projects. In a case study of energy-saving quantity assessment before and after retrofitting on a certain hospital in Shanghai,with energy simulation software TRNSYS,detailed application of this method is introduced and analyzed. The method is applied to the case of energy-saving quantity assessment to a hospital in Shanghai before and after retrofitting with the energy simulation software TRNSYS.
文摘Based on analysis of the present hydraulic impactor, a new hydraulic impactor with pressure feedback control was developed, whose structure and operation principle were introduced. The results show that the pressure of the impact system can be adjusted steplessly to change the impact energy of the impactor steplessly. By adjusting the oil flow of supply pump steplessly, the impact frequency will also be changed steplessly. So the impact energy and frequency of the new impactor can be adjusted independently and steplessly. In order to decrease the energy loss, a new kind of sleeve valve has been designed, which has features of little leakage, little pressure loss and low energy cost. The new type hydraulic impactor can be operated under various conditions with decreased energy consumption and improved operation efficiency.
文摘The General Customs Administration issued a circular statingthat,based upon a decision of the State Council,in 1997 someimport and export tariff rates would be adjusted.The major con-tents of the circular are the adjustment of the import tariff rates of 4tariff lines of commodities and items under 124 tariff lines;theelimination of the export tariffs for 14 tariff lines of commodities,addition of export tariff rates for 2 kinds of precious metals andimposition of provisional export tariff rates for 4 kinds of corn-
文摘The increasing penetration of wind power presents many technical challenges to power system operations. An important challenge is the need of voltage control to maintain the terminal voltage of a wind plant to make it a PV bus like conventional generators with excitation control. In the previous work for controlling wind plant, especially the Doubly Fed Induction Generator (DFIG) system, the proportional-integral (PI) controllers are popularly applied. These approaches usually need to tune the PI controllers to obtain control gains as a tradeoff or compromise among various operating conditions. In this paper, a new voltage control approach based on a different philosophy is presented. In the proposed approach, the PI control gains for the DFIG system are dynamically adjusted based on the dynamic, continuous sensitivity which essentially indicates the dynamic relationship between the change of control gains and the desired output voltage. Hence, this control approach does not require any good estimation of fixed control gains because it has the self-learning mechanism via the dynamic sensitivity. This also gives the plug-and-play feature of DFIG controllers to make it promising in utility practices. Simulation results verify that the proposed approach performs as expected under various operating conditions.
文摘The pavement strength is very important for the evaluation of backlog maintenance. The current trend in many developing countries used pavement conditions index-PCI in estimating maintenance costs. The PCI can only justify periodic and routine recurrent maintenance. The condition strength is rarely determined in a flexible pavement creating an opportunity for back long maintenance. This paper reports the study conducted to develop and improve the algorithm for estimating the adjusted structure number to estimate the remaining thickness of the flexible pavement. The analysis of eight ways of computing structure numbers from FWD data ware analyzed and found that the improvement of the HDM 3 - 4 models can influence the usefulness of data collected from road asset management in Tanzania. The algorithm for estimating structural numbers from CBR was improved to compute adjusted structural numbers finally used to estimate the remaining life of the flexible pavement. The analysis of the network of about 6900 km including ST and AM was found that 64.72% were very good, 12% were Good, 10% were fair and 7.84% were poor and 5.4% were very poor.
文摘Since October 2008,China's social consumption of electricity had,for the first time,grown negatively compared to the same period of the previous year,and in November the negative growth range further expanded. The major pressure faced by the electricity industry has now turned from the contradiction between coal and electricity to electricity quantity. This is undoubtedly a true and new test to electricity enterprises which get used to high growth but are now suffering great losses. The reform of electricity system has already been in great difficulties and now is getting into a more serious situation. In order to help readers improve their knowledge and understanding of the current tough situation faced by the electricity industry and discuss how to alleviate and get through the difficulty resulted from the economic crisis "encountered once every one hundred years" by joint efforts of all parties concerned,a Seminar on Crisis and Countermeasures for Electricity Industry was held on November 20,2008. Here are some extracts from the speeches of four experts.
文摘The tentative tariff rate for partial import and export products was adjusted since November 1^(st) of 2006.Total 58 imported commodities will be imposed lower tentative
基金Project supported by the National Key Research and Development Program of China(Grant Nos.2017YFB0405700 and 2016YFB0400400)the Young Scientists Fund of the National Natural Science Foundation of China(Grant Nos.51602331 and 61404146)the Shanghai Science and Technology Innovation Action Plan Program,China(Grant No.17511106200)
文摘This paper reports the sensitive effect of photoluminescence peak intensity and transmittance affected by B, Al, and N dopants in fluorescent 4H-SiC single crystals. The crystalline type, doping concentration, photoluminescence spectra,and transmission spectra were characterized at room temperature. It is found that the doped 4H-SiC single crystal emits a warm white light covering a wide range from 460 nm to 720 nm, and the transmittance increases from ~10% to ~60%with the fluctuation of B, Al, and N ternary dopants. With a parameter of C_(D-A), defined by B, Al, and N concentration, the photoluminescence and transmittance properties can be adjusted by optimal doping regulation.
基金supported by two grants from the Key Research and Development Program of jiangsu Province (No.BE2020654 and No.BE2020655)a grant from the General Program of Jiangsu Health Commission (No.H2019040)a grant from National Key R&D Program of China (No.2017YFC0114303).
文摘This study explored a new model of Prostate Imaging Reporting and Data System(PIRADS)and adjusted prostate-specific antigen density of peripheral zone(aPSADPZ)for predicting the occurrence of prostate cancer(PCa)and clinically significant prostate cancer(csPCa).The demographic and clinical characteristics of 853 patients were recorded.Prostate-specific antigen(PSA),PSA density(PSAD),PSAD of peripheral zone(PSADPZ),aPSADPZ,and peripheral zone volume ratio(PZ-ratio)were calculated and subjected to receiver operating characteristic(ROC)curve analysis.The calibration and discrimination abilities of new nomograms were verified with the calibration curve and area under the ROC curve(AUC).The clinical benefits of these models were evaluated by decision curve analysis and clinical impact curves.The AUCs of PSA,PSAD,PSADPZ,aPSADPZ,and PZ-ratio were 0.669,0.762,0.659,0.812,and 0.748 for PCa diagnosis,while 0.713,0.788,0.694,0.828,and 0.735 for csPCa diagnosis,respectively.All nomograms displayed higher net benefit and better overall calibration than the scenarios for predicting the occurrence of PCa or csPCa.The new model significantly improved the diagnostic accuracy of PCa(0.945 vs 0.830,P<0.01)and csPCa(0.937 vs 0.845,P<0.01)compared with the base model.In addition,the number of patients with PCa and csPCa predicted by the new model was in good agreement with the actual number of patients with PCa and csPCa in high-risk threshold.This study demonstrates that aPSADPZ has a higher predictive accuracy for PCa diagnosis than the conventional indicators.Combining aPSADPZ with PIRADS can improve PCa diagnosis and avoid unnecessary biopsies.
基金supported by the UIC Research Grants with No.of(R201912 and R202010)the Curriculum Development and Teaching Enhancement with No.of(UICR0400046-21CTL)+1 种基金the Guangdong Provincial Key Laboratory of Interdisciplinary Research and Application for Data Science,BNU-HKBU United International College with No.of(2022B1212010006)Guangdong Higher Education Upgrading Plan(2021-2025)with No.of(UICR0400001-22).
文摘A uniform experimental design(UED)is an extremely used powerful and efficient methodology for designing experiments with high-dimensional inputs,limited resources and unknown underlying models.A UED enjoys the following two significant advantages:(i)It is a robust design,since it does not require to specify a model before experimenters conduct their experiments;and(ii)it provides uniformly scatter design points in the experimental domain,thus it gives a good representation of this domain with fewer experimental trials(runs).Many real-life experiments involve hundreds or thousands of active factors and thus large UEDs are needed.Constructing large UEDs using the existing techniques is an NP-hard problem,an extremely time-consuming heuristic search process and a satisfactory result is not guaranteed.This paper presents a new effective and easy technique,adjusted Gray map technique(AGMT),for constructing(nearly)UEDs with large numbers of four-level factors and runs by converting designs with s two-level factors and n runs to(nearly)UEDs with 2^(t−1)s four-level factors and 2tn runs for any t≥0 using two simple transformation functions.Theoretical justifications for the uniformity of the resulting four-level designs are given,which provide some necessary and/or sufficient conditions for obtaining(nearly)uniform four-level designs.The results show that the AGMT is much easier and better than the existing widely used techniques and it can be effectively used to simply generate new recommended large(nearly)UEDs with four-level factors.
基金This work was supported by National Institute of Allergy and Infectious Diseases[NIAID 5 UM1 AI068617].
文摘To improve the precision of estimation and power of testing hypothesis for an unconditional treatment effect in randomized clinical trials with binary outcomes,researchers and regulatory agencies recommend using g computation as a reliable method of covariate adjustment.How-ever,the practical application of g-computation is hindered by the lack of an explicit robust variance formula that can be used for different unconditional treatment effects of interest.To fill this gap,we provide explicit and robust variance estimators for g-computation estimators and demonstrate through simulations that the variance estimators can be reliably applied in practice.
基金supported by the Ministry of Science and Technology of China(MoST,2019YFA0705900)the National Natural Science Foundation of China(21935007,52025033,51873089)+1 种基金Tianjin city(20JCZDJC00740)111 Project(B12015)。
文摘Compared with organic solar cells(OSCs) adopting conventional architecture,inverted OSCs have offered generally better stability,where Zn O is the most widely used electron transporting layer(ETL) material.For ZnO-based inverted OSCs,a welltuned interface of organic(active layer)-inorganic(Zn O film) with matched surface energy(γS) is critical for both high performance and high stability.In this work,two typical calixarenes,C4A and Bu C4A,were employed as the tuning agents to adjust this organic-inorganic interface for ZnO-based inverted OSCs.As a result,with PM6:L8-BO as the active layer,significantly promoted power conversion efficiencies(PCEs) from 17.14%(for ZnO) to 18.25%(for ZnO/C4A) and 17.80%(for ZnO/Bu C4A) were achieved.Photodynamic studies indicate that the enhanced performance is due to the faster charge extraction process,the suppressed recombination and more ideal internal electric field in ZnO/calixarene-based devices.In addition,wellmatched interface energy and more ordered molecular aggregation in active layer effectively improved photostability and thermal stability for ZnO/calixarene-based devices.These results indicate that calixarenes could act as effective modifying agents of ZnO to improve inverted OSCs’ performance and stability simultaneously,and likely also stimulate calixarenes’ and other macromolecules’ broader studies in other organic electronic devices.
基金Item Sponsored by National Natural Science Foundation of China/Joint Fund for Iron and Steel Research (50874130)National Natural Science Foundation of China (50974034)
文摘The effects of adjusting technological conditions on the phosphorous enrichment of adjusted converter slag were investigated. The results showed that the phosphorus could he effectively enriched to 2CaO · SiO2 and 2CaO · SiO2-3CaO· P2O5 solid solution (SS, namely phosphorus-rich phase) to be formed with the decreasing of basicity and cooling rate. Moreover, the morphology of the phosphorus-rich phase changed from granular for the original converter slag with higher basicity to the coexistence of granular shape and rod-like for the adjusted slag with lower basicity. P2 05 content in phosphorus-rich phase exceeded 30° while the hasicity was 1.3 at the cooling rate of 1.0 ℃/min.
基金Supported by the National Natural Science Foundation of China(71862026)the China Postdoctoral Science Foundation(2018T110209)+2 种基金the Natural Science Foundation of Inner Mongolia(2018MS07006)the“13th Five Year”Plan of Educational Science Research in Inner Mongolia(NGJGH2018016)the State Scholarship Fund of China Scholarship Council(20180815502)。
文摘DEA(data envelopment analysis) models can be divided into two groups: Radial DEA and non-radial DEA, and the latter has higher discriminatory power than the former. The range adjusted measure(RAM) is an effective and widely used non-radial DEA approach. However, to the best of our knowledge, there is no literature on the integer-valued super-efficiency RAM-DEA model,especially when undesirable outputs are included. We first propose an integer-valued RAM-DEA mode with undesirable outputs and then extend this model to an integer-valued super-efficiency RAM-DEA model with undesirable outputs. Compared with other DEA models, the two novel models have many advantages: 1) They are non-oriented and non-radial DEA models, which enable decision makers to simultaneously and non-proportionally improve inputs and outputs;2) They can handle integer-valued variables and undesirable outputs, so the results obtained are more reliable;3) The results can be easily obtained as it is based on linear programming;4) The integer-valued super-efficiency RAM-DEA model with undesirable outputs can be used to accurately rank efficient DMUs. The proposed models are applied to evaluate the efficiency of China’s regional transportation systems(RTSs) considering the number of transport accidents(an undesirable output). The results help decision makers improve the performance of inefficient RTSs and analyze the strengths of efficient RTSs.
基金This study was financed by the National Key Research and Development Program of China(2018YFA0605603,2020YFA0608203),ChinaConstruction Project of Weather Modification in the Northwest China(RYSY201907),China+2 种基金Natural Science Foundation(41801017),ChinaMeteorological Scientific Research in the Public Interest(CRA-40)(201506002),ChinaChina Three Gorges Corporation(0704181).
文摘The reanalysis datasets (CRA40) have now been developed in China Meteorological Administration. We aim to compare the differences in surface air temperature (SAT) between observational that has been adjusted for urbanization bias and reanalysis data (NCEPV1, NCEPV2, ERA5, CFSR, MERRA, JRA55, 20CRV3 and CRA40) over China's Mainland during 1961–2015. The main results are presented as follows. The correlation and standard deviation between the reanalysis data and observations exhibit highly consistent interannual variability and dispersion, with the interannual SAT variability in JRA55 being closest to the observations for 1961–2015 and that of ERA5 for 1979–2015;the dispersions of 20CRV3 is most consistent with the observations for 1961–2015 and that of NCEPV1 for 1979–2015. Although annual mean SAT of the reanalysis is generally 0–2.0 ℃ lower than the observations, the bias in the SAT climatology of 20CRV3 is the least for 1961–2015 in all reanalysis datasets and that of CRA40 is the least for 1979–2015. The trends of NCEPV1 is closer to the observations than other reanalysis for 1961–2015 and that of 20CRV3 for 1979–2015. The biases in terms of interannual variability, dispersion, climatology, and linear trend are increase with altitude. Overall, in terms of the similarity of multiple measures to the urbanization bias-adjusted observations, JRA55 and CRA40 show the best performances for the periods 1961–2015 and 1979–2015 respectively in reproducing various aspects of climatological and climate change features in China's Mainland.