This study proposes a batch rapid quantitative analysis method for multiple elements by combining the advantages of standard curve(SC)and calibration-free laser-induced breakdown spectroscopy(CF-LIBS)technology to ach...This study proposes a batch rapid quantitative analysis method for multiple elements by combining the advantages of standard curve(SC)and calibration-free laser-induced breakdown spectroscopy(CF-LIBS)technology to achieve synchronous,rapid,and accurate measurement of elements in a large number of samples,namely,SC-assisted CF-LIBS.Al alloy standard samples,divided into calibration and test samples,were applied to validate the proposed method.SC was built based on the characteristic line of Pb and Cr in the calibration sample,and the contents of Pb and Cr in the test sample were calculated with relative errors of 6%and 4%,respectively.SC built using Cr with multiple characteristic lines yielded better calculation results.The relative contents of ten elements in the test sample were calculated using CF-LIBS.Subsequently,the SC-assisted CF-LIBS was executed,with the majority of the calculation relative errors falling within the range of 2%-5%.Finally,the Al and Na contents of the Al alloy were predicted.The results demonstrate that it effectively enables the rapid and accurate quantitative analysis of multiple elements after a single-element SC analysis of the tested samples.Furthermore,this quantitative analysis method was successfully applied to soil and Astragalus samples,realizing an accurate calculation of the contents of multiple elements.Thus,it is important to advance the LIBS quantitative analysis and its related applications.展开更多
Regarding the spatial profile extraction method of a multi-field co-simulation dataset,different extraction directions,locations,and numbers of profileswill greatly affect the representativeness and integrity of data....Regarding the spatial profile extraction method of a multi-field co-simulation dataset,different extraction directions,locations,and numbers of profileswill greatly affect the representativeness and integrity of data.In this study,a multi-field co-simulation data extractionmethod based on adaptive infinitesimal elements is proposed.Themultifield co-simulation dataset based on related infinitesimal elements is constructed,and the candidate directions of data profile extraction undergo dimension reduction by principal component analysis to determine the direction of data extraction.Based on the fireworks algorithm,the data profile with optimal representativeness is searched adaptively in different data extraction intervals to realize the adaptive calculation of data extraction micro-step length.The multi-field co-simulation data extraction process based on adaptive microelement is established and applied to the data extraction process of the multi-field co-simulation dataset of the sintering furnace.Compared with traditional data extraction methods for multi-field co-simulation,the approximate model constructed by the data extracted from the proposed method has higher construction efficiency.Meanwhile,the relative maximum absolute error,root mean square error,and coefficient of determination of the approximationmodel are better than those of the approximation model constructed by the data extracted from traditional methods,indicating higher accuracy,it is verified that the proposed method demonstrates sound adaptability and extraction efficiency.展开更多
The building sector plays a crucial role in the worldwide shift toward achieving net-zero emissions.Building energy efficiency standards(BEESs)are highly effective policies for reducing carbon emissions.Therefore,expl...The building sector plays a crucial role in the worldwide shift toward achieving net-zero emissions.Building energy efficiency standards(BEESs)are highly effective policies for reducing carbon emissions.Therefore,exploring the provincial variations in carbon emission efficiency(CEE)in the building sector and identifying the effect of BEESs on CEE is crucial.This study focuses on commercial buildings in China and applies a difference in differences model to evaluate the impact of BEESs on the CEE of commercial buildings.The slacks-based measure–data envelopment analysis model is employed to assess the CEE of commercial buildings in 30 Chinese provinces from 2000 to 2019.Furthermore,heterogeneous tests are used to explore how climate characteristics and economic conditions affect the efficiency of BEESs.The results indicate that BEESs positively influence the CEE of commercial buildings.Specifically,a 1%increase in the intensity of BEESs causes a 0.1484%increase in the CEE of commercial buildings.Moreover,the impact of BEESs is particularly pronounced in the southern and western provinces.This study provides valuable scientific evidence for governments to enhance BEESs implementation.展开更多
Based on the monthly precipitation data of 116 meteorological stations in Shandong Province during 1970-2021,standardized precipitation index(SPI)was calculated,and the methods of linear fitting,mutation test and Morl...Based on the monthly precipitation data of 116 meteorological stations in Shandong Province during 1970-2021,standardized precipitation index(SPI)was calculated,and the methods of linear fitting,mutation test and Morlet wavelet analysis were used to analyze the change trend and temporal and spatial distribution characteristics of SPI index in the past 52 years.The results show that there were more normal years in Shandong Province,and the frequency reached 38.46%.There was severe drought in the 1980s and more wet years after 2003.SPI index showed an upward trend in spring,summer and winter but a weak arid trend in autumn.In addition,intense dry weather was more frequent in summer.Spatially,the climate was normal or humid in most areas of Shandong Province.The regions with more wet years were located in the central and northeast Shandong and the peninsula,while the climate was normal in the southwest and north of Shandong.The areas with more dry years were mainly located in the northwest of Shandong Province.There was mainly local and global drought in Shandong Province,and the arid area showed a decreasing trend.In the past 52 years,Shandong Province experienced quasi-4 times of alternation between dry and wet climate.The long period of 21 a was the first main period,and the climate would be still wet in Shandong Province in the future.In terms of mutation,the climate in Shandong Province became humid after 2003,and 2003 was the mutation point.After the abrupt change,the climate changed from gradually drying to wetting.展开更多
Spatio-temporal analysis of drought provides valuable information for drought management and damage mitigation. In this study, the Standardized Precipitation Index at the time scale of 6 months (SPI-6) is selected to ...Spatio-temporal analysis of drought provides valuable information for drought management and damage mitigation. In this study, the Standardized Precipitation Index at the time scale of 6 months (SPI-6) is selected to reflect drought conditions in the North-Eastern coastal region of Vietnam. The drought events and their characteristics from 1981 to 2019 are detected at 9 meteorological stations and 10 Chirps rainfall stations. The spatio-temporal variation of drought in the study region is analyzed on the basis of the number, duration, severity, intensity, and peak of the detected drought events at the 19 stations. The results show that from 1981 to 2019 the drought events mainly occurred with 1-season duration and moderate intensity and peak. The number, duration, severity, and peak of the drought events were the greatest in the period 2001-2010 and were the smallest in the period 2011-2019. Among the 19 stations, the drought duration tends to decrease at 11 stations, increase at 7 stations, and has a slight variant at 1 station;the drought severity tends to decrease at 14 stations, increase at 4 stations, and has not a significant trend at 1 station;the drought intensity tends to decrease at 17 stations, increase at 1 station, and has a slight variant at 1 station;and the drought peak tends to decrease at 18 stations and increase at 1 station.展开更多
The ubiquitous power Internet of Things(UPIoT)is an intelligent service system with comprehensive state perception,efficient processing,and flexible application of information.It focuses on each link of the power syst...The ubiquitous power Internet of Things(UPIoT)is an intelligent service system with comprehensive state perception,efficient processing,and flexible application of information.It focuses on each link of the power system and makes full use of the mobile internet,artificial intelligence,and other advanced information and communication technologies in order to realize the inter-human interaction of all things in all links of the power system.This article systematically presents to the national and international organizations and agencies in charge of UPIoT layer standardization the status quo of the research on the Internet of Things(IoT)-related industry standards system.It briefly describes the generic standard classification methods,layered architecture,conceptual model,and system tables in the UPIoT application layer.Based on the principles of inheritance,innovation,and practicability,this study divides the application layer into customer service,power grid operation,integrated energy,and enterprise operation,emerging business and analyzes the standard requirements of these five fields.This study also proposes a standard plan.Finally,it summarizes the research report and provides suggestions for a follow-up work.展开更多
X-ray fluorescence (XRF) analysis utilizes particle size which is resulted from milling of a material. The milling ensures uniform and fine grained powder. The finer and more uniform the particle size is, the better t...X-ray fluorescence (XRF) analysis utilizes particle size which is resulted from milling of a material. The milling ensures uniform and fine grained powder. The finer and more uniform the particle size is, the better the result and easier it is for material quality control. To ensure uniformity in particle size and finer powder, a comparative analysis was conducted with different grinding aids and pressed pellet method was used in obtaining analysis results. Pressed pellets of cement raw meal sample milled with different grinding aids (graphite, aspirin and lithium borate) were subjected to XRF. Graphite produced better particle size uniformity with a corresponding standard deviation that made quality control of raw meal easier and better than aspirin and lithium borate.展开更多
The characteristics of drought in Xinjiang Uygur Autonomous Region(Xinjiang),China have changed due to changes in the spatiotemporal patterns of temperature and precipitation,however,the effects of temperature and pre...The characteristics of drought in Xinjiang Uygur Autonomous Region(Xinjiang),China have changed due to changes in the spatiotemporal patterns of temperature and precipitation,however,the effects of temperature and precipitation—the two most important factors influencing drought—have not yet been thoroughly explored in this region.In this study,we first calculated the standard precipitation evapotranspiration index(SPEI)in Xinjiang from 1980 to 2020 based on the monthly precipitation and monthly average temperature.Then the spatiotemporal characteristics of temperature,precipitation,and drought in Xinjiang from 1980 to 2020 were analyzed using the Theil-Sen median trend analysis method and Mann-Kendall test.A series of SPEI-based scenario-setting experiments by combining the observed and detrended climatic factors were utilized to quantify the effects of individual climatic factor(i.e.,temperature and precipitation).The results revealed that both temperature and precipitation had experienced increasing trends at most meteorological stations in Xinjiang from 1980 to 2020,especially the spring temperature and winter precipitation.Due to the influence of temperature,trends of intensifying drought have been observed at spring,summer,autumn,and annual scales.In addition,the drought trends in southern Xinjiang were more notable than those in northern Xinjiang.From 1980 to 2020,temperature trends exacerbated drought trends,but precipitation trends alleviated drought trends in Xinjiang.Most meteorological stations in Xinjiang exhibited temperature-dominated drought trend except in winter;in winter,most stations exhibited precipitation-dominated wetting trend.The findings of this study highlight the importance of the impact of temperature on drought in Xinjiang and deepen the understanding of the factors influencing drought.展开更多
AIM:To assess the theoretical advantages of magnetic endoscope imaging(MEI)over standard colonoscopies(SCs)and to compare their efficacies.METHODS:Electronic databases,including PubMed,EMBASE,the Cochrane library and ...AIM:To assess the theoretical advantages of magnetic endoscope imaging(MEI)over standard colonoscopies(SCs)and to compare their efficacies.METHODS:Electronic databases,including PubMed,EMBASE,the Cochrane library and the Science Citation Index,were searched to retrieve relevant trials.In addition,abstracts from papers presented at professional meetings and the reference lists of retrieved articles were reviewed to identify additional studies.The metaanalyses were performed using RevMan 5.1.A random effect model with the Mantel-Haenszel method was used for pooling dichotomous and continuous data.A sensitivity analysis was performed by excluding the trials with a small number of patients and by excluding the trials performed by inexperienced providers.RESULTS:Eight randomized controlled trials(RCTs),including 2967 patients,were included in the metaanalysis to compare cecal intubation rates and times,sedation dose,abdominal pain scores and the use of ancillary maneuvers between MEI and SC.The overall OR was 1.92(95%CI:1.13-3.27,eight RCTs),as indicated by the cecal intubation rate of MEI compared with SC,but MEI did not have any distinct advantage over SC for cecal intubation time(MD=-0.07,95%CI:-0.16-0.02;three RCTs).MEI did not generally result in lower pain scores.Outcomes were also analyzed for the two subgroups based on the endoscopists’experience level to evaluate cecal intubation rates.MEI presented better outcomes for non-experienced colonoscopists than experienced colonoscopists.CONCLUSION:The real-time magnetic imaging system is of benefit in training and educating inexperienced endoscopists and improves the cecal intubation rate for experienced and inexperienced endoscopists.展开更多
[Objectives]To evaluate the quality of Cardamine macrophylla Willd as Tibetan and Qiang medicinal materials,so as to improve its quality standard and evaluate the quality of C.macrophylla Willd in western Sichuan Prov...[Objectives]To evaluate the quality of Cardamine macrophylla Willd as Tibetan and Qiang medicinal materials,so as to improve its quality standard and evaluate the quality of C.macrophylla Willd in western Sichuan Province.[Methods]C.macrophylla Willd produced from western Sichuan Province was used as the sample,and the contents of moisture,total ash,acid-insoluble ash,extract,total flavonoids and quercetin in the ground part of C.macrophylla Willd were determined in accordance with the methods of Chinese Pharmacopoeia(2020 edition).With the above seven indicators as evaluation indicators,the quality of medicinal materials was comprehensively evaluated by cluster analysis and principal component analysis(PCA).[Results]According to the results of each indicator,the moisture content of C.macrophylla Willd sample should not exceed 11.00%,the total ash content should not exceed 18%,the acid-insoluble ash content should not exceed 6%,the extract content should not be less than 19%,the total flavone content(calculated by quercetin)should not be less than 2%,and the quercetin content should not be less than 0.15%.[Conclusions]The sample S7 has the best quality and S6 has the worst quality.In this study,the quantitative analysis method of total flavonoids(quercetin)and quercetin in C.macrophylla Willd was established,and the limits of each indicator were preliminarily formulated.展开更多
This paper describes the standardization of the proton-induced x-ray emission(PIXE) technique for finding the elemental composition of thick samples. For the standardization, three different samples of standard refe...This paper describes the standardization of the proton-induced x-ray emission(PIXE) technique for finding the elemental composition of thick samples. For the standardization, three different samples of standard reference materials(SRMs) were analyzed using this technique and the data were compared with the already known data of these certified SRMs. These samples were selected in order to cover the maximum range of elements in the periodic table. Each sample was irradiated for three different values of collected beam charges at three different times. A proton beam of 2.57 Me V obtained using 5UDH-II Pelletron accelerator was used for excitation of x-rays from the sample. The acquired experimental data were analyzed using the GUPIXWIN software. The results show that the SRM data and the data obtained using the PIXE technique are in good agreement.展开更多
A clustering algorithm and a probability statistics method were applied to different phases of a flight to analyze operation time during aircraft ground taxiing and airborne flight.And the clustering pattern,distribut...A clustering algorithm and a probability statistics method were applied to different phases of a flight to analyze operation time during aircraft ground taxiing and airborne flight.And the clustering pattern,distribution characteristics and dynamically changing rules of the two phases were identified.Further,an estimate method was established to measure operation time of flight legs,with creative steps of calculating individual segment separately and then integrating them accordingly.The method can both objectively and dynamically measure operation time,and accurately reflect real situation.It helps to better utilize airport slot resources and provides a strong support for air traffic flow management when scheduling flight plan in strategic and pre-tactic phases.展开更多
This retrospective analysis compared standard regimen of doxorubicin, bleomycin, vin- blastine, and dacarbazine (ABVD) with the dose-dense ABVD regimen (ABVD-21) in terms of effi- cacy and toxicity. Patients who h...This retrospective analysis compared standard regimen of doxorubicin, bleomycin, vin- blastine, and dacarbazine (ABVD) with the dose-dense ABVD regimen (ABVD-21) in terms of effi- cacy and toxicity. Patients who had early-stage unfavorable or advanced Hodgkin's lymphoma (HL) according to German Hodgkin Study Group criteria from March 1999 to February 2011 were ana- lyzed for treatment response, long-term survival and hematological toxicity. There were 85 patients in the ABVD-21 group and 118 patients in the ABVD group respectively. The complete remission rates aider completion of treatment were 92.9% and 90.7% for ABVD-21 and ABVD, respectively. During a median follow-up period of 62 months, no significant difference was found in projected 10-year progression-free survival (PFS) and overall survival (OS) rates (84.7% and 94.1% respectively for ABVD-21; 81.4% and 91.5% for ABVD). Subgroup analyses showed that ABVD-21 was signifi- cantly better than ABVD for patients with IPS〉3 in terms of PFS and OS rates. Grade 3 to 4 leuko- penia (51.8% vs. 28.8%, P=0.001) and neutropenia (57.6% vs. 39.0%, P=0.009) were more common with ABVD-21. We were led to conclude that dose-dense ABVD did not result in better tumor con- trol and overall survival than did ABVD for early-stage unfavorable HL. However, patients at high risk, for example, with IPS〉3, may benefit from dose-dense ABVD.展开更多
In this paper we study inviscid and viscid Burgers equations with initial conditions in the half plane . First we consider the Burgers equations with initial conditions admitting two and three shocks and use the HOPF-...In this paper we study inviscid and viscid Burgers equations with initial conditions in the half plane . First we consider the Burgers equations with initial conditions admitting two and three shocks and use the HOPF-COLE transformation to linearize the problems and explicitly solve them. Next we study the Burgers equation and solve the initial value problem for it. We study the asymptotic behavior of solutions and we show that the exact solution of boundary value problem for viscid Burgers equation as viscosity parameter is sufficiently small approach the shock type solution of boundary value problem for inviscid Burgers equation. We discuss both confluence and interacting shocks. In this article a new approach has been developed to find the exact solutions. The results are formulated in classical mathematics and proved with infinitesimal technique of non standard analysis.展开更多
During the product family design, it is necessary to reduce the variety of components and share common components among many products. The major benefits are lessened design efforts and reduced costs. Therefore, this ...During the product family design, it is necessary to reduce the variety of components and share common components among many products. The major benefits are lessened design efforts and reduced costs. Therefore, this paper presents an approach to standardize components of a product family. Form feature modeling for components is discussed. Based on the similarity analysis, a step by step method to standardize the feature architectures of components is described. The algorithms for standardization are identified as well. A case for standardizing components of an auto-body family is used to demonstrate the validity of this approach.展开更多
Peripheral nerves form a complex network connecting the central nervous system and the body. Injuries to peripheral nerves often lead to partial or complete loss of motor, sen- sory and autonomic functions, thus inter...Peripheral nerves form a complex network connecting the central nervous system and the body. Injuries to peripheral nerves often lead to partial or complete loss of motor, sen- sory and autonomic functions, thus interfering with many aspects of an individual's life.展开更多
In order to meet new challenges brought by the development of fuel cell electric vehicle(FCEV)industry,we are in urgent need to update and refine the safety requirements for FCEVs.To this end,GB/T 24549-2020,Fuel cell...In order to meet new challenges brought by the development of fuel cell electric vehicle(FCEV)industry,we are in urgent need to update and refine the safety requirements for FCEVs.To this end,GB/T 24549-2020,Fuel cell electric vehicles-Safety requirements,was issued on September 29,2020.This paper analyzes the main technical content of the standard as well as its similarities and differences with the 2009 Version.展开更多
Objective This study proposes to visually review the current situation and progress of standards sets by the International Organization for Standardization/Technical Committee on Traditional Chinese Medicine(ISO/TC 24...Objective This study proposes to visually review the current situation and progress of standards sets by the International Organization for Standardization/Technical Committee on Traditional Chinese Medicine(ISO/TC 249). The review aims to explore the development strategies of the standards, which will exhibit the considerable impact on the economy, trade and exchanges, and cooperation in the area of traditional Chinese medicine(TCM).Methods ISO/TC 249 standards were searched on the ISO website, and their title, proposed time, current stage, scope, and classification were obtained for further summarization. Gephi was utilized to portray the co-occurrence network graph of the ISO/TC 249 standards subject.Results In ISO/TC 249, there were 116 standards, including 81 published standards and 35 developing standards by April 30, 2022. Two withdrawal standards were published after revision, which were not counted in the total standards. The number of published standards has been increasing since the first standard was published in 2014, whose title was “Sterile acupuncture needles for single use”. Among these standards, 17.24%(20/116) standards were in review, 56.03%(65/116) in publication, 3.45%(4/116) in approval, 5.17%(6/116) in enquiry,3.45%(4/116) in committee, and 14.66%(17/116) in preparation, respectively. With 116 standards, most of the research focused on the medicament, as its classification of the International Classification for Standards(ICS) showed the proportion reaching 49.54%. The network analysis data revealed that the top five most frequent words were “materials” “root” “requirements” “products” and “system”, after removing the noise data, such as prepositions,conjunctions, and pronouns. Additionally, the word “system” co-exists with the terms “computerized” “coding” “image” “tongue” and “analysis”;the word “requirement” co-exists with“manufacturing” “decoction” “process” and “materials”;whereas the word “devices” coexists with “pulse” “electric” “skin” and “measurement”.Conclusion With the increased diversification and complexity of problems, the development of standards is also oriented to multidisciplinary fields to cultivate the interdisciplinary talents, and especially the international standardization talents of compound TCM. Multi-angle analysis, formulation, and demonstration of standards, in line with industry needs in different disciplines, enhance the availability of standards and the ability to serve the industry.展开更多
基金supported by the Major Science and TechnologyTechnol-ogy Projects in Gansu Province(No.22ZD6FA021-5)Industrial Support Project of Gansu Province(Nos.2023CYZC-19 and 2021CYZC-22)+1 种基金Science and Technol-ogy Project of Gansu Province(Nos.23YFFA0074,22JR5RA137,and 22JR5RA151)Central Leading Local Science and Technology Development Fund Projects(No.23ZYQA293).
文摘This study proposes a batch rapid quantitative analysis method for multiple elements by combining the advantages of standard curve(SC)and calibration-free laser-induced breakdown spectroscopy(CF-LIBS)technology to achieve synchronous,rapid,and accurate measurement of elements in a large number of samples,namely,SC-assisted CF-LIBS.Al alloy standard samples,divided into calibration and test samples,were applied to validate the proposed method.SC was built based on the characteristic line of Pb and Cr in the calibration sample,and the contents of Pb and Cr in the test sample were calculated with relative errors of 6%and 4%,respectively.SC built using Cr with multiple characteristic lines yielded better calculation results.The relative contents of ten elements in the test sample were calculated using CF-LIBS.Subsequently,the SC-assisted CF-LIBS was executed,with the majority of the calculation relative errors falling within the range of 2%-5%.Finally,the Al and Na contents of the Al alloy were predicted.The results demonstrate that it effectively enables the rapid and accurate quantitative analysis of multiple elements after a single-element SC analysis of the tested samples.Furthermore,this quantitative analysis method was successfully applied to soil and Astragalus samples,realizing an accurate calculation of the contents of multiple elements.Thus,it is important to advance the LIBS quantitative analysis and its related applications.
基金This work is supported by the NationalNatural Science Foundation of China(No.52075350)the Major Science and Technology Projects of Sichuan Province(No.2022ZDZX0001)the Special City-University Strategic Cooperation Project of Sichuan University and Zigong Municipality(No.2021CDZG-3).
文摘Regarding the spatial profile extraction method of a multi-field co-simulation dataset,different extraction directions,locations,and numbers of profileswill greatly affect the representativeness and integrity of data.In this study,a multi-field co-simulation data extractionmethod based on adaptive infinitesimal elements is proposed.Themultifield co-simulation dataset based on related infinitesimal elements is constructed,and the candidate directions of data profile extraction undergo dimension reduction by principal component analysis to determine the direction of data extraction.Based on the fireworks algorithm,the data profile with optimal representativeness is searched adaptively in different data extraction intervals to realize the adaptive calculation of data extraction micro-step length.The multi-field co-simulation data extraction process based on adaptive microelement is established and applied to the data extraction process of the multi-field co-simulation dataset of the sintering furnace.Compared with traditional data extraction methods for multi-field co-simulation,the approximate model constructed by the data extracted from the proposed method has higher construction efficiency.Meanwhile,the relative maximum absolute error,root mean square error,and coefficient of determination of the approximationmodel are better than those of the approximation model constructed by the data extracted from traditional methods,indicating higher accuracy,it is verified that the proposed method demonstrates sound adaptability and extraction efficiency.
基金funded by the National Social Science Foundation of China[Grant No.23CJY018]the Fundamental Research Funds for the Central Universities[Grant No.JBK2406049]+2 种基金the National Natural Science Foundation of China[Grant No.72003151],[Grant No.72173100]the Soft Science Research Program of Sichuan Province[Grant No.2022JDR0227]Projects from the Research Center on Xi Jinping’s Economic Thought,and the Fundamental Research Funds for the“Guanghua Talent Program”of the Southwestern University of Finance and Economics.
文摘The building sector plays a crucial role in the worldwide shift toward achieving net-zero emissions.Building energy efficiency standards(BEESs)are highly effective policies for reducing carbon emissions.Therefore,exploring the provincial variations in carbon emission efficiency(CEE)in the building sector and identifying the effect of BEESs on CEE is crucial.This study focuses on commercial buildings in China and applies a difference in differences model to evaluate the impact of BEESs on the CEE of commercial buildings.The slacks-based measure–data envelopment analysis model is employed to assess the CEE of commercial buildings in 30 Chinese provinces from 2000 to 2019.Furthermore,heterogeneous tests are used to explore how climate characteristics and economic conditions affect the efficiency of BEESs.The results indicate that BEESs positively influence the CEE of commercial buildings.Specifically,a 1%increase in the intensity of BEESs causes a 0.1484%increase in the CEE of commercial buildings.Moreover,the impact of BEESs is particularly pronounced in the southern and western provinces.This study provides valuable scientific evidence for governments to enhance BEESs implementation.
基金Supported by the Special Project for the Grass-roots Units of Shandong Meteorological Bureau(2023SDJC14).
文摘Based on the monthly precipitation data of 116 meteorological stations in Shandong Province during 1970-2021,standardized precipitation index(SPI)was calculated,and the methods of linear fitting,mutation test and Morlet wavelet analysis were used to analyze the change trend and temporal and spatial distribution characteristics of SPI index in the past 52 years.The results show that there were more normal years in Shandong Province,and the frequency reached 38.46%.There was severe drought in the 1980s and more wet years after 2003.SPI index showed an upward trend in spring,summer and winter but a weak arid trend in autumn.In addition,intense dry weather was more frequent in summer.Spatially,the climate was normal or humid in most areas of Shandong Province.The regions with more wet years were located in the central and northeast Shandong and the peninsula,while the climate was normal in the southwest and north of Shandong.The areas with more dry years were mainly located in the northwest of Shandong Province.There was mainly local and global drought in Shandong Province,and the arid area showed a decreasing trend.In the past 52 years,Shandong Province experienced quasi-4 times of alternation between dry and wet climate.The long period of 21 a was the first main period,and the climate would be still wet in Shandong Province in the future.In terms of mutation,the climate in Shandong Province became humid after 2003,and 2003 was the mutation point.After the abrupt change,the climate changed from gradually drying to wetting.
文摘Spatio-temporal analysis of drought provides valuable information for drought management and damage mitigation. In this study, the Standardized Precipitation Index at the time scale of 6 months (SPI-6) is selected to reflect drought conditions in the North-Eastern coastal region of Vietnam. The drought events and their characteristics from 1981 to 2019 are detected at 9 meteorological stations and 10 Chirps rainfall stations. The spatio-temporal variation of drought in the study region is analyzed on the basis of the number, duration, severity, intensity, and peak of the detected drought events at the 19 stations. The results show that from 1981 to 2019 the drought events mainly occurred with 1-season duration and moderate intensity and peak. The number, duration, severity, and peak of the drought events were the greatest in the period 2001-2010 and were the smallest in the period 2011-2019. Among the 19 stations, the drought duration tends to decrease at 11 stations, increase at 7 stations, and has a slight variant at 1 station;the drought severity tends to decrease at 14 stations, increase at 4 stations, and has not a significant trend at 1 station;the drought intensity tends to decrease at 17 stations, increase at 1 station, and has a slight variant at 1 station;and the drought peak tends to decrease at 18 stations and increase at 1 station.
基金supported by Science and Technology Foundation of State Grid Corporation of China(Ubiquitous Power Internet of Things Technical Standard System)5442HL 190008National Key Research and Development Program of China(2020YFB0905900)。
文摘The ubiquitous power Internet of Things(UPIoT)is an intelligent service system with comprehensive state perception,efficient processing,and flexible application of information.It focuses on each link of the power system and makes full use of the mobile internet,artificial intelligence,and other advanced information and communication technologies in order to realize the inter-human interaction of all things in all links of the power system.This article systematically presents to the national and international organizations and agencies in charge of UPIoT layer standardization the status quo of the research on the Internet of Things(IoT)-related industry standards system.It briefly describes the generic standard classification methods,layered architecture,conceptual model,and system tables in the UPIoT application layer.Based on the principles of inheritance,innovation,and practicability,this study divides the application layer into customer service,power grid operation,integrated energy,and enterprise operation,emerging business and analyzes the standard requirements of these five fields.This study also proposes a standard plan.Finally,it summarizes the research report and provides suggestions for a follow-up work.
文摘X-ray fluorescence (XRF) analysis utilizes particle size which is resulted from milling of a material. The milling ensures uniform and fine grained powder. The finer and more uniform the particle size is, the better the result and easier it is for material quality control. To ensure uniformity in particle size and finer powder, a comparative analysis was conducted with different grinding aids and pressed pellet method was used in obtaining analysis results. Pressed pellets of cement raw meal sample milled with different grinding aids (graphite, aspirin and lithium borate) were subjected to XRF. Graphite produced better particle size uniformity with a corresponding standard deviation that made quality control of raw meal easier and better than aspirin and lithium borate.
文摘The characteristics of drought in Xinjiang Uygur Autonomous Region(Xinjiang),China have changed due to changes in the spatiotemporal patterns of temperature and precipitation,however,the effects of temperature and precipitation—the two most important factors influencing drought—have not yet been thoroughly explored in this region.In this study,we first calculated the standard precipitation evapotranspiration index(SPEI)in Xinjiang from 1980 to 2020 based on the monthly precipitation and monthly average temperature.Then the spatiotemporal characteristics of temperature,precipitation,and drought in Xinjiang from 1980 to 2020 were analyzed using the Theil-Sen median trend analysis method and Mann-Kendall test.A series of SPEI-based scenario-setting experiments by combining the observed and detrended climatic factors were utilized to quantify the effects of individual climatic factor(i.e.,temperature and precipitation).The results revealed that both temperature and precipitation had experienced increasing trends at most meteorological stations in Xinjiang from 1980 to 2020,especially the spring temperature and winter precipitation.Due to the influence of temperature,trends of intensifying drought have been observed at spring,summer,autumn,and annual scales.In addition,the drought trends in southern Xinjiang were more notable than those in northern Xinjiang.From 1980 to 2020,temperature trends exacerbated drought trends,but precipitation trends alleviated drought trends in Xinjiang.Most meteorological stations in Xinjiang exhibited temperature-dominated drought trend except in winter;in winter,most stations exhibited precipitation-dominated wetting trend.The findings of this study highlight the importance of the impact of temperature on drought in Xinjiang and deepen the understanding of the factors influencing drought.
基金Supported by The National Natural Science Foundation of China,No.81172374Sichuan Provincial Science and Technology Department Application Infrastructure Plan,No.2013JY0154
文摘AIM:To assess the theoretical advantages of magnetic endoscope imaging(MEI)over standard colonoscopies(SCs)and to compare their efficacies.METHODS:Electronic databases,including PubMed,EMBASE,the Cochrane library and the Science Citation Index,were searched to retrieve relevant trials.In addition,abstracts from papers presented at professional meetings and the reference lists of retrieved articles were reviewed to identify additional studies.The metaanalyses were performed using RevMan 5.1.A random effect model with the Mantel-Haenszel method was used for pooling dichotomous and continuous data.A sensitivity analysis was performed by excluding the trials with a small number of patients and by excluding the trials performed by inexperienced providers.RESULTS:Eight randomized controlled trials(RCTs),including 2967 patients,were included in the metaanalysis to compare cecal intubation rates and times,sedation dose,abdominal pain scores and the use of ancillary maneuvers between MEI and SC.The overall OR was 1.92(95%CI:1.13-3.27,eight RCTs),as indicated by the cecal intubation rate of MEI compared with SC,but MEI did not have any distinct advantage over SC for cecal intubation time(MD=-0.07,95%CI:-0.16-0.02;three RCTs).MEI did not generally result in lower pain scores.Outcomes were also analyzed for the two subgroups based on the endoscopists’experience level to evaluate cecal intubation rates.MEI presented better outcomes for non-experienced colonoscopists than experienced colonoscopists.CONCLUSION:The real-time magnetic imaging system is of benefit in training and educating inexperienced endoscopists and improves the cecal intubation rate for experienced and inexperienced endoscopists.
基金Supported by Scientific Research Project for School-level Teachers of Sichuan College of Traditional Chinese Medicine in 2023 (23ZRYB08)Tibetan Plateau Ethnic Medicinal Resources Protection and Utilization Key Laboratory Open Fund Project of Southwest Minzu University (QTPEM2305).
文摘[Objectives]To evaluate the quality of Cardamine macrophylla Willd as Tibetan and Qiang medicinal materials,so as to improve its quality standard and evaluate the quality of C.macrophylla Willd in western Sichuan Province.[Methods]C.macrophylla Willd produced from western Sichuan Province was used as the sample,and the contents of moisture,total ash,acid-insoluble ash,extract,total flavonoids and quercetin in the ground part of C.macrophylla Willd were determined in accordance with the methods of Chinese Pharmacopoeia(2020 edition).With the above seven indicators as evaluation indicators,the quality of medicinal materials was comprehensively evaluated by cluster analysis and principal component analysis(PCA).[Results]According to the results of each indicator,the moisture content of C.macrophylla Willd sample should not exceed 11.00%,the total ash content should not exceed 18%,the acid-insoluble ash content should not exceed 6%,the extract content should not be less than 19%,the total flavone content(calculated by quercetin)should not be less than 2%,and the quercetin content should not be less than 0.15%.[Conclusions]The sample S7 has the best quality and S6 has the worst quality.In this study,the quantitative analysis method of total flavonoids(quercetin)and quercetin in C.macrophylla Willd was established,and the limits of each indicator were preliminarily formulated.
文摘This paper describes the standardization of the proton-induced x-ray emission(PIXE) technique for finding the elemental composition of thick samples. For the standardization, three different samples of standard reference materials(SRMs) were analyzed using this technique and the data were compared with the already known data of these certified SRMs. These samples were selected in order to cover the maximum range of elements in the periodic table. Each sample was irradiated for three different values of collected beam charges at three different times. A proton beam of 2.57 Me V obtained using 5UDH-II Pelletron accelerator was used for excitation of x-rays from the sample. The acquired experimental data were analyzed using the GUPIXWIN software. The results show that the SRM data and the data obtained using the PIXE technique are in good agreement.
基金supported by the National Natural Science Foundation of China(No.U1333202)
文摘A clustering algorithm and a probability statistics method were applied to different phases of a flight to analyze operation time during aircraft ground taxiing and airborne flight.And the clustering pattern,distribution characteristics and dynamically changing rules of the two phases were identified.Further,an estimate method was established to measure operation time of flight legs,with creative steps of calculating individual segment separately and then integrating them accordingly.The method can both objectively and dynamically measure operation time,and accurately reflect real situation.It helps to better utilize airport slot resources and provides a strong support for air traffic flow management when scheduling flight plan in strategic and pre-tactic phases.
文摘This retrospective analysis compared standard regimen of doxorubicin, bleomycin, vin- blastine, and dacarbazine (ABVD) with the dose-dense ABVD regimen (ABVD-21) in terms of effi- cacy and toxicity. Patients who had early-stage unfavorable or advanced Hodgkin's lymphoma (HL) according to German Hodgkin Study Group criteria from March 1999 to February 2011 were ana- lyzed for treatment response, long-term survival and hematological toxicity. There were 85 patients in the ABVD-21 group and 118 patients in the ABVD group respectively. The complete remission rates aider completion of treatment were 92.9% and 90.7% for ABVD-21 and ABVD, respectively. During a median follow-up period of 62 months, no significant difference was found in projected 10-year progression-free survival (PFS) and overall survival (OS) rates (84.7% and 94.1% respectively for ABVD-21; 81.4% and 91.5% for ABVD). Subgroup analyses showed that ABVD-21 was signifi- cantly better than ABVD for patients with IPS〉3 in terms of PFS and OS rates. Grade 3 to 4 leuko- penia (51.8% vs. 28.8%, P=0.001) and neutropenia (57.6% vs. 39.0%, P=0.009) were more common with ABVD-21. We were led to conclude that dose-dense ABVD did not result in better tumor con- trol and overall survival than did ABVD for early-stage unfavorable HL. However, patients at high risk, for example, with IPS〉3, may benefit from dose-dense ABVD.
文摘In this paper we study inviscid and viscid Burgers equations with initial conditions in the half plane . First we consider the Burgers equations with initial conditions admitting two and three shocks and use the HOPF-COLE transformation to linearize the problems and explicitly solve them. Next we study the Burgers equation and solve the initial value problem for it. We study the asymptotic behavior of solutions and we show that the exact solution of boundary value problem for viscid Burgers equation as viscosity parameter is sufficiently small approach the shock type solution of boundary value problem for inviscid Burgers equation. We discuss both confluence and interacting shocks. In this article a new approach has been developed to find the exact solutions. The results are formulated in classical mathematics and proved with infinitesimal technique of non standard analysis.
基金Science & Technology Foundation of Shanghai (Grant No.05JC14021)
文摘During the product family design, it is necessary to reduce the variety of components and share common components among many products. The major benefits are lessened design efforts and reduced costs. Therefore, this paper presents an approach to standardize components of a product family. Form feature modeling for components is discussed. Based on the similarity analysis, a step by step method to standardize the feature architectures of components is described. The algorithms for standardization are identified as well. A case for standardizing components of an auto-body family is used to demonstrate the validity of this approach.
基金funding from the European Community’s Seventh Framework Program(FP7-HEALTH-2011)under grant agreement,No.278612(BIOHYBRID)
文摘Peripheral nerves form a complex network connecting the central nervous system and the body. Injuries to peripheral nerves often lead to partial or complete loss of motor, sen- sory and autonomic functions, thus interfering with many aspects of an individual's life.
文摘In order to meet new challenges brought by the development of fuel cell electric vehicle(FCEV)industry,we are in urgent need to update and refine the safety requirements for FCEVs.To this end,GB/T 24549-2020,Fuel cell electric vehicles-Safety requirements,was issued on September 29,2020.This paper analyzes the main technical content of the standard as well as its similarities and differences with the 2009 Version.
基金National Key Research and Development Program of China (2018YFC1707606)Sichuan Provincial Administration of Traditional Chinese Medicine (2022MS500)+1 种基金Chengdu Science and Technology Department Project(2019-YF09-00185-SN)Xinglin Scholar Research Promotion Project of Chengdu University of Traditional Chinese Medicine (MPRC2021022)。
文摘Objective This study proposes to visually review the current situation and progress of standards sets by the International Organization for Standardization/Technical Committee on Traditional Chinese Medicine(ISO/TC 249). The review aims to explore the development strategies of the standards, which will exhibit the considerable impact on the economy, trade and exchanges, and cooperation in the area of traditional Chinese medicine(TCM).Methods ISO/TC 249 standards were searched on the ISO website, and their title, proposed time, current stage, scope, and classification were obtained for further summarization. Gephi was utilized to portray the co-occurrence network graph of the ISO/TC 249 standards subject.Results In ISO/TC 249, there were 116 standards, including 81 published standards and 35 developing standards by April 30, 2022. Two withdrawal standards were published after revision, which were not counted in the total standards. The number of published standards has been increasing since the first standard was published in 2014, whose title was “Sterile acupuncture needles for single use”. Among these standards, 17.24%(20/116) standards were in review, 56.03%(65/116) in publication, 3.45%(4/116) in approval, 5.17%(6/116) in enquiry,3.45%(4/116) in committee, and 14.66%(17/116) in preparation, respectively. With 116 standards, most of the research focused on the medicament, as its classification of the International Classification for Standards(ICS) showed the proportion reaching 49.54%. The network analysis data revealed that the top five most frequent words were “materials” “root” “requirements” “products” and “system”, after removing the noise data, such as prepositions,conjunctions, and pronouns. Additionally, the word “system” co-exists with the terms “computerized” “coding” “image” “tongue” and “analysis”;the word “requirement” co-exists with“manufacturing” “decoction” “process” and “materials”;whereas the word “devices” coexists with “pulse” “electric” “skin” and “measurement”.Conclusion With the increased diversification and complexity of problems, the development of standards is also oriented to multidisciplinary fields to cultivate the interdisciplinary talents, and especially the international standardization talents of compound TCM. Multi-angle analysis, formulation, and demonstration of standards, in line with industry needs in different disciplines, enhance the availability of standards and the ability to serve the industry.