The most difficult and delicate part of the learning process is assessment.Assessment is difficult because during his/her accomplishment the teacher has to consider not only the acquisition of knowledge from students,...The most difficult and delicate part of the learning process is assessment.Assessment is difficult because during his/her accomplishment the teacher has to consider not only the acquisition of knowledge from students,but also the overall degree of development of their competencies.It is delicate,because through assessment we can influence the emotional side of students and their“willingness”to learn.Despite these facts,teachers need to evaluate students during the learning process.The purpose of the research is to find out what is the perception of teachers about the level of evaluation of students with final grade.The overall results showed that 89%of teachers agree,9%of them have a neutral attitude,and 2%do not agree that the evaluation of students with a final grade is done taking into account many aspects and using many methods,the overall average of the results,M=4.36.Based on the empirical results,it was found that teachers who have completed assessment training have a more positive approach to student assessment,as the average score is higher than teachers who have not completed assessment training.From the qualitative results it was understood that the Teachers did not encounter any difficulties during the assessment of the students.展开更多
This study explored the application of machine learning techniques for flood prediction and analysis in southern Nigeria. Machine learning is an artificial intelligence technique that uses computer-based instructions ...This study explored the application of machine learning techniques for flood prediction and analysis in southern Nigeria. Machine learning is an artificial intelligence technique that uses computer-based instructions to analyze and transform data into useful information to enable systems to make predictions. Traditional methods of flood prediction and analysis often fall short of providing accurate and timely information for effective disaster management. More so, numerical forecasting of flood disasters in the 19th century is not very accurate due to its inability to simplify complex atmospheric dynamics into simple equations. Here, we used Machine learning (ML) techniques including Random Forest (RF), Logistic Regression (LR), Naïve Bayes (NB), Support Vector Machine (SVM), and Neural Networks (NN) to model the complex physical processes that cause floods. The dataset contains 59 cases with the goal feature “Event-Type”, including 39 cases of floods and 20 cases of flood/rainstorms. Based on comparison of assessment metrics from models created using historical records, the result shows that NB performed better than all other techniques, followed by RF. The developed model can be used to predict the frequency of flood incidents. The majority of flood scenarios demonstrate that the event poses a significant risk to people’s lives. Therefore, each of the emergency response elements requires adequate knowledge of the flood incidences, continuous early warning service and accurate prediction model. This study can expand knowledge and research on flood predictive modeling in vulnerable areas to inform effective and sustainable contingency planning, policy, and management actions on flood disaster incidents, especially in other technologically underdeveloped settings.展开更多
With the increasing requirement for the protection of arable land, monitor- ing the grades of arable land quality is becoming more important, which can accu- rately and fully reflect the current situation and developm...With the increasing requirement for the protection of arable land, monitor- ing the grades of arable land quality is becoming more important, which can accu- rately and fully reflect the current situation and development trends of arable land quality. It is also an important measure for protecting the quality of arable land. in the present study, the distribution and changes of arable lands of different gradient types and grades in Lingchuan County, Guangxi Zhuang Autonomous Region in 2015 were monitored and evaluated, to analyze the trends and reasons for the changes in the quality and productivity of arable lands, and to provide references for dynamic monitoring of the quality of arable land.展开更多
Based on the natural disaster risk evaluation mode, a quantitative danger degree evaluation model was developed to evaluate the danger degree of earth dam reservoir staged operation in the flood season. A formula for ...Based on the natural disaster risk evaluation mode, a quantitative danger degree evaluation model was developed to evaluate the danger degree of earth dam reservoir staged operation in the flood season. A formula for the overtopping risk rate of the earth dam reservoir staged operation was established, with consideration of the joint effect of flood and wind waves in the flood sub-seasons with the Monte Carlo method, and the integrated overtopping risk rate for the whole flood season was obtained via the total probability approach. A composite normalized function was used to transform the dam overtopping risk rate into the danger degree, on a scale of 0-1. Danger degree gradating criteria were divided by four significant characteristic values of the dam overtopping rate, and corresponding guidelines for danger evaluation are explained in detail in this paper. Examples indicated that the dam overtopping danger degree of the Chengbihe Reservoir in China was 0.33-0.57, within the range of moderate danger level, and the flood-limiting water level (FLWL) can be adjusted to 185.00 m for the early and main flood seasons, and 185.00-187.50 m for the late flood season. The proposed quantitative model offers a theoretical basis for determination of the value of the danger degree of an earth dam reservoir under normal operation as well as the optimal scheduling scheme for the reservoir in each stage of the flood season.展开更多
Using geographic information system to study flooded area and damage evaluation has been a hotspot in environmental disaster research for years. In this paper, a model for flooded area calculation and damage evaluatio...Using geographic information system to study flooded area and damage evaluation has been a hotspot in environmental disaster research for years. In this paper, a model for flooded area calculation and damage evaluation is presented. Flooding is divided into two types: ‘soruce flood’ and ‘non-source flood’. The source-flood area calculation is based on seed spread algorithm. The flood damage evaluation is calculated by overlaying the flooded ara range with thematic maps and relating the results to other social and economic data. To raise the operational efficiency of the model, a skipping approach is used to speed seed spread algorithm and all thematic maps are converted to raster format before overlay analysis. The accuracy of flooded area calculation and damage evaluation is mainly dependent upon the resolution and precision of the digital elevation model (DEM) data, upon the accuracy of registering all raster layers, and upon the quality of economic information. This model has been successfully used in the Zhejiang Province Comprehensive Water Management Information System developed by the authors. The applications show that this model is especially useful for most counties of China and other developing countries.展开更多
Precise comprehensive evaluation of flood disaster loss is significant for the prevention and mitigation of flood disasters. Here, one of the difficulties involved is how to establish a model capable of describing the...Precise comprehensive evaluation of flood disaster loss is significant for the prevention and mitigation of flood disasters. Here, one of the difficulties involved is how to establish a model capable of describing the complex relation between the input and output data of the system of flood disaster loss. Genetic programming (GP) solves problems by using ideas from genetic algorithm and generates computer programs automatically. In this study a new method named the evaluation of the grade of flood disaster loss (EGFD) on the basis of improved genetic programming (IGP) is presented (IGP-EGFD). The flood disaster area and the direct economic loss are taken as the evaluation indexes of flood disaster loss. Obviously that the larger the evaluation index value, the larger the corresponding value of the grade of flood disaster loss is. Consequently the IGP code is designed to make the value of the grade of flood disaster be an increasing function of the index value. The result of the application of the IGP-EGFD model to Henan Province shows that a good function expression can be obtained within a bigger searched function space; and the model is of high precision and considerable practical significance. Thus, IGP-EGFD can be widely used in automatic modeling and other evaluation systems.展开更多
Coal mining under buildings certainly causes surface movement and deformation, therefore, it brings about deformation even fracture for buildings. It is an important task to evaluate correcly the buildings’ damage gr...Coal mining under buildings certainly causes surface movement and deformation, therefore, it brings about deformation even fracture for buildings. It is an important task to evaluate correcly the buildings’ damage grabe caused by coal mining. Fuzzy comprehensive evaluation,considering some factors of buildings’ fracture, has been applied to analyze the masonry structure buildings’ damage grade affer coal mining in this paper. It provides a scientific basis for buildings’reidercement before mining and maintenance or compensation after mining.展开更多
In this paper, the Global Satellite Mapping of Precipitation Moving Vector with Kalman filter (GSMaP_MVK) was evaluated and corrected at daily time scales with a spatial resolution of 0.1°;latitude/longitude. The...In this paper, the Global Satellite Mapping of Precipitation Moving Vector with Kalman filter (GSMaP_MVK) was evaluated and corrected at daily time scales with a spatial resolution of 0.1°;latitude/longitude. The reference data came from thirty-four rain gauges on Kyushu Island, Japan. This study focused on the GSMaP_MVK’s ability to detect heavy rainfall patterns that may lead to flooding. Statistical analysis was used to evaluate the GSMaP_MVK data both quantitatively and qualitatively. The statistical analysis included the relative bias (B), the mean error (E), the Nash-Sutcliffe coefficient (CNS), the Root Mean Square Error (RMSE) and the correlation coefficient (r). In addition, Generalized Additive Models (GAMs) were used to conduct GSMaP_MVK data correction. The results of these analyses indicate that GSMaP_MVK data have lower values than observed data and may be significantly underestimated during heavy rainfall. By applying GAM to bias correction, GSMaP_MVK’s ability to detect heavy rainfall was improved. In addition, GAM for bias correction could effectively be applied for significant underestimates of GSMaP_ MVK (i.e., bias of more than 55%). GAM is a new approach to predict rainfall amount for flood and landslide monitoring of satellite base precipitation, especially in areas where rain gauge data are limited.展开更多
The rapid changing near source, multi-stream depositional environment of conglomerate reservoirs leads to severe heterogeneity, complex lithology and physical properties, and large changes of oil layer resistivity. Qu...The rapid changing near source, multi-stream depositional environment of conglomerate reservoirs leads to severe heterogeneity, complex lithology and physical properties, and large changes of oil layer resistivity. Quantitative evaluation of water-flooded layers has become an important but difficult focus for secondary development of oilfields. In this paper, based on the analysis of current problems in quantitative evaluation of water-flooded layers, the Kexia Group conglomerate reservoir of the Sixth District in the Karamay Oilfield was studied. Eight types of conglomerate reservoir lithology were identified effectively by a data mining method combined with the data from sealed coring wells, and then a multi-parameter model for quantitative evaluation of the water-flooded layers of the main oil-bearing lithology was developed. Water production rate, oil saturation and oil productivity index were selected as the characteristic parameters for quantitative evaluation of water-flooded layers of conglomerate reservoirs. Finally, quantitative evaluation criteria and identification rules for water-flooded layers of main oil-bearing lithology formed by integration of the three characteristic parameters of water-flooded layer and undisturbed formation resistivity. This method has been used in evaluation of the water-flooded layers of a conglomerate reservoir in the Karamay Oilfield and achieved good results, improving the interpretation accuracy and compliance rate. It will provide technical support for avoiding perforation of high water-bearing layers and for adjustment of developmental programs.展开更多
On the basis of historical yearly drought and flood grades from A.D.1470 to A.D.1949, the ten-year mean precipitation in the rainy season in Wuhan district was reconstructed by means of statistical method. The re...On the basis of historical yearly drought and flood grades from A.D.1470 to A.D.1949, the ten-year mean precipitation in the rainy season in Wuhan district was reconstructed by means of statistical method. The reconstructing method was testified to be simple and effective.展开更多
The fast evaluation method of flood damages was explored with the combination of high technologies, such as remote sensing (RS) and geographic information system (GIS), namely the land classification and extraction of...The fast evaluation method of flood damages was explored with the combination of high technologies, such as remote sensing (RS) and geographic information system (GIS), namely the land classification and extraction of flood areas were accomplished in RS image processing software, ENVI, the flood damages information system, digital terrain model and flood damages evaluation information system were developed on GIS platform GeoMedia. The problem of the combination of multi-source data was addressed, furthermore, the problems of how to build the flood damages evaluation model and the inundating elevation model were deeply probed, the calculating formulas were also given. Case study result shows that the evaluation models are correct and data are reliable, we can use it to evaluate real-time flood damages and provide evidences for decision-making of leaders, moreover, it is of great instructive significance to the research of flood damages evaluation theories.展开更多
The evaluation method, model and process for the flood and waterlogging disaster condition by GIS,RS and GPS technology and the method for setting up disaster condition database, dyke database and historical disaster ...The evaluation method, model and process for the flood and waterlogging disaster condition by GIS,RS and GPS technology and the method for setting up disaster condition database, dyke database and historical disaster damage database are presented. An index of flood damage degree(FDD) used to evaluate the relative degree of disaster loss and divide flood and waterlogging area is suggested. The value of flood damage degree can be calculated as follows :taking the various disaster losses of sample area in a base year as standard value and computing the ratios of various disaster loss values in different areas and years to the standard flood disaster loss values, then summing up the weighted ratios. The computed results are the value of flood damage degree in the every year. The macroscopic flood disaster distribution can be evaluated by the values of flood loss degree.展开更多
目的运用循证医学方法对腕踝针干预术后疼痛的疗效和安全性进行系统评价和Grade评价。方法计算机检索中国知网、万方、维普、中国生物医学文献数据库、PubMed、Embase、Web of Science、Cochrane Library中关于腕踝针干预术后疼痛的随...目的运用循证医学方法对腕踝针干预术后疼痛的疗效和安全性进行系统评价和Grade评价。方法计算机检索中国知网、万方、维普、中国生物医学文献数据库、PubMed、Embase、Web of Science、Cochrane Library中关于腕踝针干预术后疼痛的随机对照试验,检索时限为建库至2023年10月。采用RevMan 5.4软件进行Meta分析。结果纳入23篇文献,共计1968例患者,Meta分析结果显示,与常规治疗相比,腕踝针能够提高术后疼痛患者的总有效率[OR=4.42,95%CI(2.60,7.50),P<0.001],术后镇痛泵药量使用减少[MD=-9.03,95%CI(-12.09,-5.98),P<0.001],术后疼痛评分降低[MD=-1.39,95%CI(-1.68,-1.09),P<0.001],可减少不良反应发生率[RR=0.40,95%CI(0.32,0.48),P<0.001]以及临床满意度[OR=3.94,95%CI(2.40,6.48),P<0.001]。Grade证据分级结果显示:总有效率、不良反应发生率和临床满意度3项结局指标为中等质量证据,VAS评分指标为低质量证据,镇痛泵药量使用指标为极低质量证据。结论腕踝针可提高总有效率,减少术后镇痛药用量,不良反应少,安全性高,为患者提供了一种安全有效的镇痛方式。展开更多
为了系统评价参芪扶正注射液联合常规治疗作为干预措施对慢性阻塞性肺疾病(chronic obstructive pulmonary disease,COPD)患者的临床疗效和安全性。检索中国国家知识基础设施(China national knowledge infrastructure,CNKI)、PubMed、...为了系统评价参芪扶正注射液联合常规治疗作为干预措施对慢性阻塞性肺疾病(chronic obstructive pulmonary disease,COPD)患者的临床疗效和安全性。检索中国国家知识基础设施(China national knowledge infrastructure,CNKI)、PubMed、万方数据知识服务平台(Wanfang Data)、维普中文科技期刊数据库(Weipu China science and technology journal database,VIP)等数据库,筛选并纳入2023年6月18日以前发表的参芪扶正注射液联合常规疗法治疗COPD患者的随机对照试验(randomized controlled trials,RCT),采用Cochrane风险评价工具及评估、发展和评价建议分级(grading of recommendations assessment,development and evaluation,GRADE)系统进行文献证据质量评价,用RevMan 5.4软件对临床疗效及安全性指标进行Meta分析。结果表明,共纳入16项RCTs,1 486例患者。Meta分析结果显示,参芪扶正注射液辅助治疗可提高患者总有效率和第1秒用力呼气容积/用力肺活量比值(forced expiratory volume in one second/forced vital capacity,FEV1/FVC)指标,与对照组相比具有优势(P<0.000 01、P<0.000 1);不良反应少,无严重不良反应(adverse drug reactions,ADR),两组对比无统计学差异(P=0.32);GRADE评价结果显示,有效率及不良反应指标的证据质量均为中等级,肺功能为低等级。可见参芪扶正注射辅助治疗COPD可以提高患者临床疗效,改善肺功能,且具有良好的安全性。但所纳入研究具有局限性,证据质量不高,仍需结合中药辨证使用特点,规范实验方案,开展更多的高质量RCT研究。展开更多
目的系统评价补肾方剂改善高龄女性自然妊娠结局的临床疗效和安全性。方法检索中国知网、万方数据库、维普数据库、SinoMed、PubMed、Web of Science、Cochrane Library、Embase等数据库建库至2022年6月收录的补肾方剂改善高龄女性自然...目的系统评价补肾方剂改善高龄女性自然妊娠结局的临床疗效和安全性。方法检索中国知网、万方数据库、维普数据库、SinoMed、PubMed、Web of Science、Cochrane Library、Embase等数据库建库至2022年6月收录的补肾方剂改善高龄女性自然妊娠结局的随机对照研究(RCT)。运用偏倚风险工具进行质量评估,使用RevMan软件进行Meta分析。结果共纳入14篇RCT。Meta分析结果显示:补肾方剂联合西药治疗在提高妊娠率[RR=1.71,95%CI(1.45,2.01),P<0.00001]、降低卵泡刺激素(FSH)水平[SMD=-1.63,95%CI(-2.84,-0.43),P=0.008]、提高雌二醇(E_(2))水平[SMD=3.97,95%CI(1.76,6.17),P=0.0004]、增加排卵期子宫内膜厚度[SMD=2.12,95%CI(1.07,3.18),P<0.0001]方面均优于西药组;且补肾方剂单独使用在提高妊娠率[RR=1.94,95%CI(1.31,2.88),P=0.001]、降低FSH水平[SMD=-0.48,95%CI(-0.74,-0.22),P=0.0003]方面也具有显著疗效。结论与西医治疗比较,补肾方剂可以显著改善高龄女性自然妊娠结局,且不良反应较少,但仍需更多高质量、大样本、多中心的RCT予以验证。展开更多
目的:评价温针灸治疗原发性痛经的有效性和安全性。方法:根据PRISMA指南进行系统综述和荟萃分析。收集PubMed、Web of Science、EMBASE、Cochrane Library、中国知网、维普、万方、中国生物医学数据库自建库至2023年5月的随机对照试验...目的:评价温针灸治疗原发性痛经的有效性和安全性。方法:根据PRISMA指南进行系统综述和荟萃分析。收集PubMed、Web of Science、EMBASE、Cochrane Library、中国知网、维普、万方、中国生物医学数据库自建库至2023年5月的随机对照试验。使用Review Manager 5.4对所有获得的数据进行分析。结果:温针灸治疗原发性痛经在提高临床疗效{风险比(RR)=1.21,95%置信区间(CI)[1.16,1.25],P<0.00001},改善阻力指数(RI){均数差(MD)=-0.14,95%CI[-0.19,-0.08],P<0.00001}、搏动指数(PI)(MD=-0.55,95%CI[-0.69,-0.40],P<0.00001)、β-内啡肽(β-EP){标准化均数差(SMD)=1.36,95%CI[0.90,1.82],P<0.00001}、痛经证候积分(MD=-1.82,95%CI[-2.77,-0.87],P=0.0002)、疼痛视觉模拟评分法(VAS)评分(MD=-1.16,95%CI[-1.48,-0.83],P<0.00001)方面的作用优于单独的常规治疗,并且在不良反应发生率(P=0.01)方面低于对照组。证据质量等级评价结果显示临床疗效为中级,其他多为低级。结论:温针灸治疗原发性痛经的疗效明确,并且具有一定的安全性。展开更多
文摘The most difficult and delicate part of the learning process is assessment.Assessment is difficult because during his/her accomplishment the teacher has to consider not only the acquisition of knowledge from students,but also the overall degree of development of their competencies.It is delicate,because through assessment we can influence the emotional side of students and their“willingness”to learn.Despite these facts,teachers need to evaluate students during the learning process.The purpose of the research is to find out what is the perception of teachers about the level of evaluation of students with final grade.The overall results showed that 89%of teachers agree,9%of them have a neutral attitude,and 2%do not agree that the evaluation of students with a final grade is done taking into account many aspects and using many methods,the overall average of the results,M=4.36.Based on the empirical results,it was found that teachers who have completed assessment training have a more positive approach to student assessment,as the average score is higher than teachers who have not completed assessment training.From the qualitative results it was understood that the Teachers did not encounter any difficulties during the assessment of the students.
文摘This study explored the application of machine learning techniques for flood prediction and analysis in southern Nigeria. Machine learning is an artificial intelligence technique that uses computer-based instructions to analyze and transform data into useful information to enable systems to make predictions. Traditional methods of flood prediction and analysis often fall short of providing accurate and timely information for effective disaster management. More so, numerical forecasting of flood disasters in the 19th century is not very accurate due to its inability to simplify complex atmospheric dynamics into simple equations. Here, we used Machine learning (ML) techniques including Random Forest (RF), Logistic Regression (LR), Naïve Bayes (NB), Support Vector Machine (SVM), and Neural Networks (NN) to model the complex physical processes that cause floods. The dataset contains 59 cases with the goal feature “Event-Type”, including 39 cases of floods and 20 cases of flood/rainstorms. Based on comparison of assessment metrics from models created using historical records, the result shows that NB performed better than all other techniques, followed by RF. The developed model can be used to predict the frequency of flood incidents. The majority of flood scenarios demonstrate that the event poses a significant risk to people’s lives. Therefore, each of the emergency response elements requires adequate knowledge of the flood incidences, continuous early warning service and accurate prediction model. This study can expand knowledge and research on flood predictive modeling in vulnerable areas to inform effective and sustainable contingency planning, policy, and management actions on flood disaster incidents, especially in other technologically underdeveloped settings.
文摘With the increasing requirement for the protection of arable land, monitor- ing the grades of arable land quality is becoming more important, which can accu- rately and fully reflect the current situation and development trends of arable land quality. It is also an important measure for protecting the quality of arable land. in the present study, the distribution and changes of arable lands of different gradient types and grades in Lingchuan County, Guangxi Zhuang Autonomous Region in 2015 were monitored and evaluated, to analyze the trends and reasons for the changes in the quality and productivity of arable lands, and to provide references for dynamic monitoring of the quality of arable land.
基金supported by the National Natural Science Foundation of China(Grants No.51569003 and 51579059)the Natural Science Foundation of Guangxi Province(Grant No.2017GXNSFAA198361)the Innovation Project of Guangxi Graduate Education(Grant No.YCSW2017052)
文摘Based on the natural disaster risk evaluation mode, a quantitative danger degree evaluation model was developed to evaluate the danger degree of earth dam reservoir staged operation in the flood season. A formula for the overtopping risk rate of the earth dam reservoir staged operation was established, with consideration of the joint effect of flood and wind waves in the flood sub-seasons with the Monte Carlo method, and the integrated overtopping risk rate for the whole flood season was obtained via the total probability approach. A composite normalized function was used to transform the dam overtopping risk rate into the danger degree, on a scale of 0-1. Danger degree gradating criteria were divided by four significant characteristic values of the dam overtopping rate, and corresponding guidelines for danger evaluation are explained in detail in this paper. Examples indicated that the dam overtopping danger degree of the Chengbihe Reservoir in China was 0.33-0.57, within the range of moderate danger level, and the flood-limiting water level (FLWL) can be adjusted to 185.00 m for the early and main flood seasons, and 185.00-187.50 m for the late flood season. The proposed quantitative model offers a theoretical basis for determination of the value of the danger degree of an earth dam reservoir under normal operation as well as the optimal scheduling scheme for the reservoir in each stage of the flood season.
基金Project of National Ninth Five-Year Plan, 96-D042
文摘Using geographic information system to study flooded area and damage evaluation has been a hotspot in environmental disaster research for years. In this paper, a model for flooded area calculation and damage evaluation is presented. Flooding is divided into two types: ‘soruce flood’ and ‘non-source flood’. The source-flood area calculation is based on seed spread algorithm. The flood damage evaluation is calculated by overlaying the flooded ara range with thematic maps and relating the results to other social and economic data. To raise the operational efficiency of the model, a skipping approach is used to speed seed spread algorithm and all thematic maps are converted to raster format before overlay analysis. The accuracy of flooded area calculation and damage evaluation is mainly dependent upon the resolution and precision of the digital elevation model (DEM) data, upon the accuracy of registering all raster layers, and upon the quality of economic information. This model has been successfully used in the Zhejiang Province Comprehensive Water Management Information System developed by the authors. The applications show that this model is especially useful for most counties of China and other developing countries.
基金The authors would like to acknowledge the funding support of the National Natural Science Foundation of China (No. 50579009, 70425001).
文摘Precise comprehensive evaluation of flood disaster loss is significant for the prevention and mitigation of flood disasters. Here, one of the difficulties involved is how to establish a model capable of describing the complex relation between the input and output data of the system of flood disaster loss. Genetic programming (GP) solves problems by using ideas from genetic algorithm and generates computer programs automatically. In this study a new method named the evaluation of the grade of flood disaster loss (EGFD) on the basis of improved genetic programming (IGP) is presented (IGP-EGFD). The flood disaster area and the direct economic loss are taken as the evaluation indexes of flood disaster loss. Obviously that the larger the evaluation index value, the larger the corresponding value of the grade of flood disaster loss is. Consequently the IGP code is designed to make the value of the grade of flood disaster be an increasing function of the index value. The result of the application of the IGP-EGFD model to Henan Province shows that a good function expression can be obtained within a bigger searched function space; and the model is of high precision and considerable practical significance. Thus, IGP-EGFD can be widely used in automatic modeling and other evaluation systems.
文摘Coal mining under buildings certainly causes surface movement and deformation, therefore, it brings about deformation even fracture for buildings. It is an important task to evaluate correcly the buildings’ damage grabe caused by coal mining. Fuzzy comprehensive evaluation,considering some factors of buildings’ fracture, has been applied to analyze the masonry structure buildings’ damage grade affer coal mining in this paper. It provides a scientific basis for buildings’reidercement before mining and maintenance or compensation after mining.
文摘In this paper, the Global Satellite Mapping of Precipitation Moving Vector with Kalman filter (GSMaP_MVK) was evaluated and corrected at daily time scales with a spatial resolution of 0.1°;latitude/longitude. The reference data came from thirty-four rain gauges on Kyushu Island, Japan. This study focused on the GSMaP_MVK’s ability to detect heavy rainfall patterns that may lead to flooding. Statistical analysis was used to evaluate the GSMaP_MVK data both quantitatively and qualitatively. The statistical analysis included the relative bias (B), the mean error (E), the Nash-Sutcliffe coefficient (CNS), the Root Mean Square Error (RMSE) and the correlation coefficient (r). In addition, Generalized Additive Models (GAMs) were used to conduct GSMaP_MVK data correction. The results of these analyses indicate that GSMaP_MVK data have lower values than observed data and may be significantly underestimated during heavy rainfall. By applying GAM to bias correction, GSMaP_MVK’s ability to detect heavy rainfall was improved. In addition, GAM for bias correction could effectively be applied for significant underestimates of GSMaP_ MVK (i.e., bias of more than 55%). GAM is a new approach to predict rainfall amount for flood and landslide monitoring of satellite base precipitation, especially in areas where rain gauge data are limited.
文摘The rapid changing near source, multi-stream depositional environment of conglomerate reservoirs leads to severe heterogeneity, complex lithology and physical properties, and large changes of oil layer resistivity. Quantitative evaluation of water-flooded layers has become an important but difficult focus for secondary development of oilfields. In this paper, based on the analysis of current problems in quantitative evaluation of water-flooded layers, the Kexia Group conglomerate reservoir of the Sixth District in the Karamay Oilfield was studied. Eight types of conglomerate reservoir lithology were identified effectively by a data mining method combined with the data from sealed coring wells, and then a multi-parameter model for quantitative evaluation of the water-flooded layers of the main oil-bearing lithology was developed. Water production rate, oil saturation and oil productivity index were selected as the characteristic parameters for quantitative evaluation of water-flooded layers of conglomerate reservoirs. Finally, quantitative evaluation criteria and identification rules for water-flooded layers of main oil-bearing lithology formed by integration of the three characteristic parameters of water-flooded layer and undisturbed formation resistivity. This method has been used in evaluation of the water-flooded layers of a conglomerate reservoir in the Karamay Oilfield and achieved good results, improving the interpretation accuracy and compliance rate. It will provide technical support for avoiding perforation of high water-bearing layers and for adjustment of developmental programs.
文摘On the basis of historical yearly drought and flood grades from A.D.1470 to A.D.1949, the ten-year mean precipitation in the rainy season in Wuhan district was reconstructed by means of statistical method. The reconstructing method was testified to be simple and effective.
文摘The fast evaluation method of flood damages was explored with the combination of high technologies, such as remote sensing (RS) and geographic information system (GIS), namely the land classification and extraction of flood areas were accomplished in RS image processing software, ENVI, the flood damages information system, digital terrain model and flood damages evaluation information system were developed on GIS platform GeoMedia. The problem of the combination of multi-source data was addressed, furthermore, the problems of how to build the flood damages evaluation model and the inundating elevation model were deeply probed, the calculating formulas were also given. Case study result shows that the evaluation models are correct and data are reliable, we can use it to evaluate real-time flood damages and provide evidences for decision-making of leaders, moreover, it is of great instructive significance to the research of flood damages evaluation theories.
文摘The evaluation method, model and process for the flood and waterlogging disaster condition by GIS,RS and GPS technology and the method for setting up disaster condition database, dyke database and historical disaster damage database are presented. An index of flood damage degree(FDD) used to evaluate the relative degree of disaster loss and divide flood and waterlogging area is suggested. The value of flood damage degree can be calculated as follows :taking the various disaster losses of sample area in a base year as standard value and computing the ratios of various disaster loss values in different areas and years to the standard flood disaster loss values, then summing up the weighted ratios. The computed results are the value of flood damage degree in the every year. The macroscopic flood disaster distribution can be evaluated by the values of flood loss degree.
文摘目的运用循证医学方法对腕踝针干预术后疼痛的疗效和安全性进行系统评价和Grade评价。方法计算机检索中国知网、万方、维普、中国生物医学文献数据库、PubMed、Embase、Web of Science、Cochrane Library中关于腕踝针干预术后疼痛的随机对照试验,检索时限为建库至2023年10月。采用RevMan 5.4软件进行Meta分析。结果纳入23篇文献,共计1968例患者,Meta分析结果显示,与常规治疗相比,腕踝针能够提高术后疼痛患者的总有效率[OR=4.42,95%CI(2.60,7.50),P<0.001],术后镇痛泵药量使用减少[MD=-9.03,95%CI(-12.09,-5.98),P<0.001],术后疼痛评分降低[MD=-1.39,95%CI(-1.68,-1.09),P<0.001],可减少不良反应发生率[RR=0.40,95%CI(0.32,0.48),P<0.001]以及临床满意度[OR=3.94,95%CI(2.40,6.48),P<0.001]。Grade证据分级结果显示:总有效率、不良反应发生率和临床满意度3项结局指标为中等质量证据,VAS评分指标为低质量证据,镇痛泵药量使用指标为极低质量证据。结论腕踝针可提高总有效率,减少术后镇痛药用量,不良反应少,安全性高,为患者提供了一种安全有效的镇痛方式。
文摘为了系统评价参芪扶正注射液联合常规治疗作为干预措施对慢性阻塞性肺疾病(chronic obstructive pulmonary disease,COPD)患者的临床疗效和安全性。检索中国国家知识基础设施(China national knowledge infrastructure,CNKI)、PubMed、万方数据知识服务平台(Wanfang Data)、维普中文科技期刊数据库(Weipu China science and technology journal database,VIP)等数据库,筛选并纳入2023年6月18日以前发表的参芪扶正注射液联合常规疗法治疗COPD患者的随机对照试验(randomized controlled trials,RCT),采用Cochrane风险评价工具及评估、发展和评价建议分级(grading of recommendations assessment,development and evaluation,GRADE)系统进行文献证据质量评价,用RevMan 5.4软件对临床疗效及安全性指标进行Meta分析。结果表明,共纳入16项RCTs,1 486例患者。Meta分析结果显示,参芪扶正注射液辅助治疗可提高患者总有效率和第1秒用力呼气容积/用力肺活量比值(forced expiratory volume in one second/forced vital capacity,FEV1/FVC)指标,与对照组相比具有优势(P<0.000 01、P<0.000 1);不良反应少,无严重不良反应(adverse drug reactions,ADR),两组对比无统计学差异(P=0.32);GRADE评价结果显示,有效率及不良反应指标的证据质量均为中等级,肺功能为低等级。可见参芪扶正注射辅助治疗COPD可以提高患者临床疗效,改善肺功能,且具有良好的安全性。但所纳入研究具有局限性,证据质量不高,仍需结合中药辨证使用特点,规范实验方案,开展更多的高质量RCT研究。
文摘目的系统评价补肾方剂改善高龄女性自然妊娠结局的临床疗效和安全性。方法检索中国知网、万方数据库、维普数据库、SinoMed、PubMed、Web of Science、Cochrane Library、Embase等数据库建库至2022年6月收录的补肾方剂改善高龄女性自然妊娠结局的随机对照研究(RCT)。运用偏倚风险工具进行质量评估,使用RevMan软件进行Meta分析。结果共纳入14篇RCT。Meta分析结果显示:补肾方剂联合西药治疗在提高妊娠率[RR=1.71,95%CI(1.45,2.01),P<0.00001]、降低卵泡刺激素(FSH)水平[SMD=-1.63,95%CI(-2.84,-0.43),P=0.008]、提高雌二醇(E_(2))水平[SMD=3.97,95%CI(1.76,6.17),P=0.0004]、增加排卵期子宫内膜厚度[SMD=2.12,95%CI(1.07,3.18),P<0.0001]方面均优于西药组;且补肾方剂单独使用在提高妊娠率[RR=1.94,95%CI(1.31,2.88),P=0.001]、降低FSH水平[SMD=-0.48,95%CI(-0.74,-0.22),P=0.0003]方面也具有显著疗效。结论与西医治疗比较,补肾方剂可以显著改善高龄女性自然妊娠结局,且不良反应较少,但仍需更多高质量、大样本、多中心的RCT予以验证。