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In situ digital testing method for quality assessment of soft soil improvement with polyurethane
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作者 X.F.Wang C.J.Wang +2 位作者 W.V.Yue Z.J.Zhang Z.Q.Yue 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第5期1732-1748,共17页
This study purposes an in situ testing method on quality assessment of soil improvement.Factual drilling data includes the spatial distribution and in situ strength of untreated and treated soil along three different ... This study purposes an in situ testing method on quality assessment of soil improvement.Factual drilling data includes the spatial distribution and in situ strength of untreated and treated soil along three different drillholes measured by on-site drilling monitoring method.These factual drilling data can characterize the degree of soil improvement by penetration injection with permeable polyurethane.Result from on-site drilling monitoring shows that the linear zones represent constant drilling speeds shown in the plot of drill bit advancement vs.net drilling time,which indicates the spatial distributions of soil profile.The soil profile at the study site is composed of four layers,which includes fill,untreated silty clay,treated silty clay,and mucky soil.The results of soil profile are verified by the parallel site loggings.The constant drilling speeds profile the coring-resistant strength of drilled soils.By comparing with the untreated silty clay,the constant drilling speeds of the treated silty clay have been decreased by 13.0-62.8%.Two drilling-speed-based indices of 61.2%and 65.6%are proposed to assess the decreased average drilling speed and the increased in situ strength of treated silty clay.Laboratory tests,i.e.uniaxial compressive strength(UCS)test,have been performed with core sample to investigate and characterize in situ strength by comparing that with drilling speeds.Results show that the average predicted strengths of treated silty clay are 2.4-6.9 times higher than the average measured strength of untreated silty clay.The UCS-based indices of 374.5%and 344.2%verified the quality assessment(QA)results by this new in situ method.This method provides a cost-effective tool for quality assessment of soil improvement by utilizing the digital drilling data. 展开更多
关键词 Drilling process monitoring system Hydraulic rotary drilling process Constant drilling speed Soil improvement quality assessment
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Assessment of Effects of Qinshan Nuclear Power Station on the Ecological Environment and Water Quality of its Adjacent Waters after its Running
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作者 Yang Guanming, He Dehua, Wang Zhengfang, Wang Chunsheng, Chen Yongshou, Hu Xigang (Second Institute of Oceanography, SOA) 《Marine Science Bulletin》 CAS 1999年第2期1-8,共8页
On the basis of the data of biological and nonbiological factors collected respectively from 1989 to 1990 and from 1995 to 1996 in the waters nearby the Qinshan Nuclear Power Station, the ecological environment and wa... On the basis of the data of biological and nonbiological factors collected respectively from 1989 to 1990 and from 1995 to 1996 in the waters nearby the Qinshan Nuclear Power Station, the ecological environment and water quality of the waters are analyzed and assessed in the paper. The results show: (a) the surveyed area has the typical ecological characteristics of high tidal range estuary, rich nutrients and low biological productivity, (b) tide, runoff and offshore seawater intrusion are the key factors which result in seasonal and annual changes of various biological and non-biological factors, (c) the risking of seawater eutrophication index is resulted from enormous amount of the discharges of industrial and domestic sewage, (d) because the survey area is located in a high tidal-range estuary, thermal effluent from cooling system does not induce significant temperature changes, ( e) the first stage project of Qinshan nuclear power station has no notable impacts on the ecological environment in 展开更多
关键词 nuclear power STATION WATERS ECOLOGICAL environment water quality ASSESSMENT
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A Comparative Study of Different Methods on Quality Assessment of Soil Environment Polluted by Zinc in Agricultural Production Areas——A Case Study in Shulan City of Jilin Province
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作者 李润林 姚艳敏 于士凯 《Agricultural Science & Technology》 CAS 2012年第10期2191-2196,共6页
[Objective] The aim was to explore evaluated precision on quality of soil environment polluted with zinc in agricultural production areas and to provide references for verification of production area.[Method] In Shula... [Objective] The aim was to explore evaluated precision on quality of soil environment polluted with zinc in agricultural production areas and to provide references for verification of production area.[Method] In Shulan City in Jilin Province,soils were sampled and analyzed in a laboratory using single-factor pollution index and GIS based spatial interpolation.The quality of environment polluted with zinc was assessed and related methods were compared according to Environment Quality Standard of Green Food Production Area.[Result] Spatial interpolation of zinc in soils based on GIS proved more precise than traditional methods;cokriging method with co-factors was higher in precision than common cokriging;cokriging method with zinc and organic matter was higher in precision than cokriging with zinc alone.[Conclusion] Quality assessment on environment polluted with zinc based on GIS interpolation is more scientific and reasonable than traditional methods. 展开更多
关键词 Agricultural production area Soil environment quality Assessment COKRIGING Ordinary kriging
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Comprehensive Assessment of Seawater Quality Based on an Improved Attribute Recognition Model 被引量:4
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作者 ZHANG Libing CHENG Jilin +1 位作者 JIN Juliang JIANG Xiaohong 《Journal of Ocean University of China》 SCIE CAS 2006年第4期300-304,共5页
The attribute recognition model (ARM) has been widely used to make comprehensive assessment in many engineering fields, such as environment, ecology, and economy. However, large numbers of experiments indicate that th... The attribute recognition model (ARM) has been widely used to make comprehensive assessment in many engineering fields, such as environment, ecology, and economy. However, large numbers of experiments indicate that the value of weight vector has no relativity to its initial value but depends on the data of Quality Standard and actual samples. In the present study, the ARM is enhanced with the technique of data driving, which means some more groups of data from the Quality Standard are selected with the uniform random method to make the calculation of weight values more rational and more scientific. This improved attribute recognition model (IARM) is applied to a real case of assessment on seawater quality. The given example shows that the IARM has the merits of being simple in principle, easy to operate, and capable of producing objective results, and is therefore of use in evaluation problems in marine environment science. 展开更多
关键词 comprehensive assessment seawater quality improved attribute recognition model
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The Analysis and Remediation Technology of the Pollution of the Groundwater Environment in Longkou Plain, China
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作者 Panpan Meng 《Journal of Environmental Science and Engineering(A)》 2021年第2期45-51,共7页
In order to study the groundwater environment in the Longkou plain,48 groups of water samples are collected,consisting of 7 groups of surface water samples and 41 groups of groundwater samples.The quality of groundwat... In order to study the groundwater environment in the Longkou plain,48 groups of water samples are collected,consisting of 7 groups of surface water samples and 41 groups of groundwater samples.The quality of groundwater in the Longkou Plain is poor,with class V water quality accounting for more than 90%,and no class I,II water quality,sporadic distribution of Class III and IV water quality.The influencing factors of water quality are mainly inorganic indicators such as nitrate,total hardness,chloride,salinity and sulfate,the detection rate of heavy metals is low.Nitrate is the main pollution index in this area,and the increase of nitrate content is closely related to the construction of underground reservoir.Based on the characteristics of groundwater pollution in the Longkou Plain,the in-situ chemical remediation of groundwater pollution is proposed. 展开更多
关键词 Groundwater environment quality assessment pollution analysis remediation technology.
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Quality Assessment by Evaluation of Network-based Teaching Environments
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作者 Wolfram Laaser 《开放教育研究》 CSSCI 2005年第2期59-64,共6页
This paper introduced the objectives, instruments and methods for the evaluation firstly, Then the paper exemplified the criteria to evaluate the learntng management system and online courses. At the end, the author c... This paper introduced the objectives, instruments and methods for the evaluation firstly, Then the paper exemplified the criteria to evaluate the learntng management system and online courses. At the end, the author came the conclusion that the results of evaluation should be implemented continuously to implore the systems services and submitted to the scientific community to check their rigidity and validity. 展开更多
关键词 教学环境 教学质量 教学评估 远程开放教育
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Statistical Analysis of Process Monitoring Data for Software Process Improvement and Its Application 被引量:2
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作者 Kazuhiro Esaki Yuki Ichinose Shigeru Yamada 《American Journal of Operations Research》 2012年第1期43-50,共8页
Software projects influenced by many human factors generate various risks. In order to develop highly quality software, it is important to respond to these risks reasonably and promptly. In addition, it is not easy fo... Software projects influenced by many human factors generate various risks. In order to develop highly quality software, it is important to respond to these risks reasonably and promptly. In addition, it is not easy for project managers to deal with these risks completely. Therefore, it is essential to manage the process quality by promoting activities of process monitoring and design quality assessment. In this paper, we discuss statistical data analysis for actual project management activities in process monitoring and design quality assessment, and analyze the effects for these software process improvement quantitatively by applying the methods of multivariate analysis. Then, we show how process factors affect the management measures of QCD (Quality, Cost, Delivery) by applying the multiple regression analyses to observed process monitoring data. Further, we quantitatively evaluate the effect by performing design quality assessment based on the principal component analysis and the factor analysis. As a result of analysis, we show that the design quality assessment activities are so effective for software process improvement. Further, based on the result of quantitative project assessment, we discuss the usefulness of process monitoring progress assessment by using a software reliability growth model. This result may enable us to give a useful quantitative measure of product release determination. 展开更多
关键词 Software PROCESS improvement PROCESS Monitoring Design quality ASSESSMENT Multiple Regression ANALYSIS Principal COMPONENT ANALYSIS FACTOR ANALYSIS QUANTITATIVE Project ASSESSMENT
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Integrated Assessment of Mineral Resources and Environmentin Mid-South of Shandong Province
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作者 Wei Min Yao Yonghui Wang Xueping Faculty of Earth Resources, China University Geosciences, Wuhan 430074 《Journal of Earth Science》 SCIE CAS CSCD 2000年第2期76-78,共3页
On the bases of the field survey and a large number of testing data, we process the qualitative and quantitative assessment of the mine environment in the mid south of Shandong Province using the following grade Ⅰ fa... On the bases of the field survey and a large number of testing data, we process the qualitative and quantitative assessment of the mine environment in the mid south of Shandong Province using the following grade Ⅰ factors:the surface subsidence in mining area, the three wastes of mine industries, the pollution sources, the surface water pollution, the underground water pollution and the air pollution. By means of emitting factor judgment and water quality indexes, we locate pollution sources, main pollutants, pollution type and pollution grade in the study area. Using the MAPGIS, we draw a zonality map of the mine environment. This paper attempts to offer a concrete example, including valuable assessment method, data and conclusion, for the assessment of mine environment from the integrated assessment of mineral resources and mine environment. This research is oriented towards the sustainable development and the ecological environment optimization. 展开更多
关键词 integrated assessment of resources and environment the quality assessment of environment water quality index emitting factor judgment liquid waste capacity per 10 000 yuan production value ecological environment optimization.
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Factors Influencing Patient-Centered Care in the Primary Health Care Settings: The Impact of the Pandemic Crisis and Nurses’ Experience
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作者 Adepeju Lateef Euphemia Mbali Mhlongo 《Open Journal of Nursing》 2022年第3期220-233,共14页
Patient-centered care has over the past decades, been recognized worldwide as an important component of the health system giving a wider dimension to high-quality healthcare and service delivery. The impact on healthc... Patient-centered care has over the past decades, been recognized worldwide as an important component of the health system giving a wider dimension to high-quality healthcare and service delivery. The impact on healthcare and services to the patient is the nurses’ ability to create a friendly rapport with the patients. Yet, the majority in the rural Primary Health Care facilities are still facing many challenges in demonstrating patient-centeredness services to the community. Thus, the objective of this study is to explore and describe the factors influencing patient-centered care provision and nurses’ experience in Primary Health Care facilities. An exploratory qualitative approach with purposive sampling was used to gather data. Individual interviews with 35 nurses were conducted using a semi-structure interview guide question in the Primary Health Care settings in Nigeria. Each of the interviews with the nurses lasted for 25 minutes to one hour. All interviews were audio-taped, and transcribed verbatim using Microsoft Word. The transcripts were read and re-read, coded using NVivo version 12 software to organize the relevant information and categorized them into themes and sub-themes. Thematic analysis guided this study. The findings revealed three themes and sub-themes. The impact of environmental factors with two subthemes—suitable working environment and coordinated care;resources—shortage of staff and inadequate resources as sub-themes, and lastly, cultural sensitivity and religious influence—communication. Poor implementation of PCC strategies in most of the PHC facilities could lead to poor patient care and a lack of job satisfaction among nurses. This study identified that nurses have both negative and positive experience in providing patient-centered care health services. Providing patient-centered care in the Primary Health Care setting promotes the goal of achieving universal health coverage in Nigeria if the government would prioritize nurses’ pay, employ more staff, provide a conducive working environment, and opportunities for further training programs for nurses to enable and empower them with the necessary knowledge and skills. This, in turn, will translate into a range of outcomes that are socially valued, such as health responsiveness, health coverage and fairness. 展开更多
关键词 Healthcare Service NURSING quality Care improvement Work environment Patient-Centered Care And Primary Health Care
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EBD Methodology in the Education in the Mid-west University of China
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作者 Yi Hong Deng Xiaoguang 《学术界》 CSSCI 北大核心 2017年第1期303-308,共6页
Due to the impact of globalization,more and more universities in China dedicate to improve the quality of undergraduate education.The particular emphasis was given on the universities in Mid-west university of China,w... Due to the impact of globalization,more and more universities in China dedicate to improve the quality of undergraduate education.The particular emphasis was given on the universities in Mid-west university of China,where the economics and transportation facility are relatively less developed comparing to other regions.In contrast of the traditional methodologies of social science,this research was conducted using an engineering design methodology,called Environment-Based Design(EBD).The EBD procedure allows to derive the solutions step-by-step based on a holistic environment analysis and thus an identification of major challenges. 展开更多
关键词 中国中西部 教育系统 高校 工程设计方法 教育质量 交通设施 传统方法 社会科学
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Water quality characteristics and assessment of Yongding New River by improved comprehensive water quality identification index based on game theory 被引量:10
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作者 Yu Liu Yucheng Hu +2 位作者 Yumei Hu Yuqi Gao Zhenying Liu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2021年第6期40-52,共13页
The Yongding New River is essential for the water supplies of Tianjin.To date,there is no comprehensive report that assesses the year-round water quality of the Yongding New River Main stream.Moreover,little attention... The Yongding New River is essential for the water supplies of Tianjin.To date,there is no comprehensive report that assesses the year-round water quality of the Yongding New River Main stream.Moreover,little attention has been given to determining a combined weight for improving the traditional comprehensive water quality identification index(ICWQII)by the game theory.Seven water quality parameters were investigated monthly along the main stream of the Yongding New River from May 2018 to April 2019.Organic contaminants and nitrogen pollution were mainly caused by point sources pollution,and the total phosphorus mainly by non-point source pollution.Dramatic spatio-temporal variations of water quality parameters were jointly caused by different pollutant sources and hydrometeorological factors.In terms of this study,an improved comprehensive water quality identification index(ICWQII)based on entropy weight or variation coefficient and traditional CWQII underestimated the water qualities,and an ICWQII based on the superstandard multiple method overvalued the assessments.By contrast,water qualities assessments done with an ICWQII based on the game theory matched perfectly with the practical situation.The ICWQII based on game theory proposed in this study takes into account not only the degree of disorder and variation of water quality data,but also the influence of standard-exceeded pollution indicators,whose results are relatively reasonable.All findings and the ICWQII based on game theory can provide scientific support for decisions related to the water environment management of the Yongding New River and other waters. 展开更多
关键词 Water quality assessment improved comprehensive water quality identification index Game theory Combined weight Spatio-temporal variation Yongding New River
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ArcGIS-Based Rural Drinking Water Quality Health Risk Assessment 被引量:2
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作者 Fuquan NI Guodong LIU +2 位作者 Jian YE Huazhun REN Shangchun YANG 《Journal of Water Resource and Protection》 2009年第5期351-361,共11页
Aiming at the unsafe of water quality which is the core problem in rural drinking water safety, the study col-lected 221 water samples of rural drinking water sources in Ya'an and detected the concentrations of th... Aiming at the unsafe of water quality which is the core problem in rural drinking water safety, the study col-lected 221 water samples of rural drinking water sources in Ya'an and detected the concentrations of the car-cinogen and the non-carcinogen. Based on the analysis of water environment characteristics and the identifi-cation of water environment health risk source of Sichuan Ya’an City, which includes seven counties and a district and is the typical region of the western margin of Sichuan Basin, this study calculated and analyzed the carcinogenic risk (R) and non-carcinogenic risk (hazard index, HI) by applying the health risk model recommended by the US National Research Council of National Academy of Science. Then, taking advan-tage of the geo-statistic spatial analysis function of ArcGIS, this study analyzed the assessment result data (R and HI), selected the proper interpolation approach and educed R and HI spatial distribution maps of the study area. R and HI of the single factor and integrate factors were evaluated and thus obtained the following conclusions: For one thing, the cancerous risk indexes of the vast majority of water sources (about 94%) is the level of 10-7 and it belong to the safety extension. The main carcinogen in the water sources are As, Cr6+ and Pb, their concentrations are in the ranges of 0.004-0.01, 0.005, 0.01mg/l respectively and such water source mainly distributed in Yucheng district and Mingshan county. For another, the non-cancerous hazard indexes of the vast majority of water sources (about 98%) is also less than the limit value 1 and will not harm the local residents. The health risk of non-carcinogen comes mainly from As and fluoride, their concentra-tions are in the ranges of 0.004-0.01 and 0.1-4.2mg/l respectively. The results of the integrate factors health risk assessment showed that the total cancerous risk were still at the level of 10-6, only 12 drinking water source investigation sites (5%) exceeded the drinking water management standard value of EPA (the limit value is 10-6);the total non-cancerous hazard indexes are still in the range of 10-2-10-1, and will not harm the local residents either, only 18 drinking water source investigation sites (8%) exceeded the drinking water management standard value of EPA(the limit value is 1).The densely populated areas such as Yucheng Dis-trict, Tianquan County, Yingjing County and Shimian County are where the four contaminating materials, i.e., As, Cr6+, Pb and fluoride should be monitored with emphasis. Study results disclosed the health risk control indexes of source water quality of the studied area and thus provided the scientific basis for the water quality control of water sources. This study had worked efficiently in practice. Compared with the same kind of methods which had been found, the paper had the outstanding results for the health risk assessment of the rural drinking water safety. 展开更多
关键词 WATER SOURCES WATER environment WATER quality HEALTH Risk Assessment ARCGIS Geo-Statistical Analysis Ya’an CITY
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A strategy for population pharmaceutical quality assessment based on quality by design 被引量:2
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作者 Yu Zhao Changqin Hu +2 位作者 Shangchen Yao Lihui Yin Xiaomei Ling 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2021年第5期588-595,共8页
From a regulatory perspective,drug quality consistency evaluation must concern different processes used for the same drug.In this study,an assessment strategy based on quality by design(QbD)was developed for populatio... From a regulatory perspective,drug quality consistency evaluation must concern different processes used for the same drug.In this study,an assessment strategy based on quality by design(QbD)was developed for population pharmaceutical quality evaluation.A descriptive analysis method based on QbD concept was first established to characterize the process by critical evaluation attributes(CEAs).Then quantitative analysis method based on an improved statistical process control(SPC)method was established to investigate the process indicators(PIs)in the process population,such as mean distribution,batch-to-batch difference and abnormal quality probability.After that rules for risk assessment were established based on the SPC limitations and parameters.Both the SPC parameters of the CEAs and the risk of PIs were visualized according to the interaction test results to obtain a better understanding of the population pharmaceutical quality.Finally,an assessment strategy was built and applied to generic drug consistency assessment,process risk assessment and quality trend tracking.The strategy demonstrated in this study could help reveal quality consistency from the perspective of process control and process risk,and further show the recent development status of domestic pharmaceutical production processes.In addition,a process risk assessment and population quality trend tracking provide databased information for approval.Not only can this information serve as a further basis for decisionmaking by the regulatory authority regarding early warnings,but it can also reduce some avoidable adverse reactions.With continuous addition of data,dynamic population pharmaceutical quality is meaningful for emergencies and decision-making regarding drug regulation. 展开更多
关键词 Population pharmaceutical quality quality by design(QbD) Crucial evaluation attributes(CEAs) Process indicators(PIs) improved statistical process control(SPC) Risk assessment
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Leveraging Six Sigma Tools and Methodology to Improve Student English Language Performance at Elementary School 被引量:1
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作者 Mazen Arafeh 《American Journal of Operations Research》 2016年第4期261-274,共15页
Purpose: The purpose of this paper is to discuss how the Six Sigma (SS) methodology can be used to improve the performance of students in English as a second language and enhance the teaching process by utilizing qual... Purpose: The purpose of this paper is to discuss how the Six Sigma (SS) methodology can be used to improve the performance of students in English as a second language and enhance the teaching process by utilizing quality tools in an educational environment. Design/Methodology/Approach: The paper uses the different quality improvement tools within the Define, Measure, Analyze, Improve and Control (DMAIC) phases to improve student performance in an English language class at a private school. Findings: Quality tools, such as cause and effect diagrams and quality function deployment, have been successfully applied within the Six Sigma DMAIC framework in the educational sector to improve the performance of students and enhance the teaching process. Practical Implications: This paper helps school administrations to analyze student performance and implement improvement actions to improve their performance. Originality/Value: The principal objective of this paper is to demonstrate how quality improvement tools can be introduced and successfully applied in an elementary school to improve student performance and communication between the school administration, teachers and parents. 展开更多
关键词 Six Sigma DMAIC Educational environment quality improvement Tools Teaching Process
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Outpatient telephonic transitional care after hospital discharge improves survival in cirrhotic patients
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作者 Bhavana Bhagya Rao Anastasia Sobotka +2 位作者 Rocio Lopez Carlos Romero-Marrero William Carey 《World Journal of Hepatology》 CAS 2019年第8期646-655,共10页
BACKGROUND Intervention to improve outcomes in cirrhotic patients (CP) after hospital discharge often focus on 30 d readmission rate (RR). However, recent studies suggest dissociation between RR and survival. At our c... BACKGROUND Intervention to improve outcomes in cirrhotic patients (CP) after hospital discharge often focus on 30 d readmission rate (RR). However, recent studies suggest dissociation between RR and survival. At our center, CP are now offered outpatient telephonic transitional care (OTTC) by a care coordinator for 30 d after hospital discharge. AIM To determine the effect of OTTC on survival in CP. METHODS In this cohort study from a tertiary center, CP who received OTTC formed the intervention group. They were compared with a control group discharged during the same period. Mortality and RR were compared between the groups. RESULTS After OTTC introduction, 194 CP were discharged. After applying exclusion criteria, 169 CP (51% male, mean age 58 years ± 12 years) were included. OTTC group comprised 76 patients and was compared with 93 controls. Baseline disease and index admission related characteristics were not significantly different between the groups. The intervention group showed significantly higher 6 mo survival compared to controls (84.2% vs 68.8%;P = 0.03), while RR at 1, 3, and 6 mo were comparable. On multivariable analysis, the intervention group showed lower odds for mortality compared to the controls (hazard ratio: 0.4;95% confidence interval: 0.2-0.82;P = 0.012), while higher model for endstage liver disease scores were associated with higher mortality (hazard ratio: 1.05;95% confidence interval: 1.01-1.1;P = 0.024).CONCLUSION CP provided OTTC had higher 6 mo survival compared to controls without a difference in RR. Use of RR to gauge quality of care provided during hospitalization or subsequent transitional care programs should be revisited. 展开更多
关键词 quality improveMENT Transitional CARE OUTPATIENT monitoring OUTCOMES assessment
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税收营商环境优化与企业全要素生产率——来自税务系统“放管服”改革的经验证据 被引量:7
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作者 储德银 程扬帆 《南开经济研究》 CSSCI 北大核心 2024年第4期45-65,共21页
优化税收营商环境不仅是提高企业生产效率和推动企业转型升级的重要战略举措,而且对实现经济高质量发展具有十分重要的现实意义。本文基于2013—2020年A股上市公司数据,并借助税务系统“放管服”改革试点这一准自然实验,构建多期双重差... 优化税收营商环境不仅是提高企业生产效率和推动企业转型升级的重要战略举措,而且对实现经济高质量发展具有十分重要的现实意义。本文基于2013—2020年A股上市公司数据,并借助税务系统“放管服”改革试点这一准自然实验,构建多期双重差分模型,实证考察了税收营商环境优化对企业全要素生产率的影响。研究表明,税务系统“放管服”改革对企业全要素生产率具有显著的正向影响,且该结论经过一系列稳健性检验依然成立。机制检验结果显示,税收营商环境优化主要是通过降低交易成本水平、提升资源配置效率以及鼓励技术创新来提高企业全要素生产率。异质性分析表明,对于中西部地区企业、非国有企业、环境不确定性高企业和成熟期企业,税收营商环境优化对企业全要素生产率的促进作用相对更加突出。随后的进一步分析表明,税收营商环境优化在提升企业全要素生产率的同时显著促进了企业经营规模扩大和产业链扩张。本文以上研究结论不仅能使我们更好地认识税收营商环境优化的经济效应,更是为培育有利于激发市场主体活力及推动企业提质增效的税收营商环境提供了经验证据与有益启示。 展开更多
关键词 “放管服”改革 税收营商环境 企业全要素生产率 企业提质增效
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我国生态环境治理对经济高质量发展影响的实证研究 被引量:1
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作者 刘志雄 张久玥 陈红惠 《生态经济》 北大核心 2024年第6期172-178,共7页
生态环境治理能力现代化是生态环境与经济实现协调发展的保障。论文深入研究了我国生态环境治理对经济高质量发展的影响,通过构建生态环境治理指标体系,以绿色全要素生产率作为经济高质量发展的代理指标,以生态环境质量改善和生态环境... 生态环境治理能力现代化是生态环境与经济实现协调发展的保障。论文深入研究了我国生态环境治理对经济高质量发展的影响,通过构建生态环境治理指标体系,以绿色全要素生产率作为经济高质量发展的代理指标,以生态环境质量改善和生态环境治理保障作为中介变量进行实证。研究发现,生态环境治理能够促进经济高质量发展,但具有区域异质性。生态环境质量改善和生态环境治理保障具有中介作用。最后建议各地区加大绿色生态环境治理建设、因地制宜开展生态环境治理工作、各部门注重生态环境质量改善和完善生态环境治理保障。 展开更多
关键词 生态环境治理 经济高质量发展 绿色全要素生产率 生态环境质量改善 生态环境治理保障
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基于遥感生态指数改进模型的沱江流域生态环境质量时空变化及驱动力研究
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作者 赵晓燕 谈树成 +3 位作者 张素 李永平 吴汉 王超 《水土保持学报》 CSCD 北大核心 2024年第5期151-163,共13页
[目的]沱江流域面临严重的水土流失、水环境污染和土壤侵蚀等生态环境问题,开展流域生态环境质量评价对推动长江上游生态环境保护和流域社会经济高质量可持续发展具有重要意义。[方法]基于谷歌地球引擎平台,选取2000-2020年的Landsat遥... [目的]沱江流域面临严重的水土流失、水环境污染和土壤侵蚀等生态环境问题,开展流域生态环境质量评价对推动长江上游生态环境保护和流域社会经济高质量可持续发展具有重要意义。[方法]基于谷歌地球引擎平台,选取2000-2020年的Landsat遥感影像,以绿度、湿度、热度、干度、生物丰度指数构建生态环境质量评价模型,采用变异系数、一元线性回归和空间自相关分析方法对流域内生态环境质量的时空演变格局进行分析,并运用最优参数地理探测器模型(optimal parameter geographic detector model,OPGD)对其驱动力进行探测。[结果](1)2000-2020年,沱江流域生态环境质量多年平均值为0.66,等级以良为主,占比为63.01%。成都周边区县、内江、自贡、泸州等城镇地区生态环境质量较差,呈现南北低中间高的空间分布格局。(2)沱江流域生态环境质量总体呈下降趋势,生态环境质量变差的趋势显著,轻微退化和显著退化面积占比分别为19.75%和5.88%。人口密度大,社会经济发展水平高的城镇化地区,生态环境质量以较高波动为主,占比为18.15%。(3)2000-2020年沱江流域全局自相关莫兰指数范围为0.769~0.870,主要分布在第1象限和第3象限,局部自相关的高-高集聚区和低-低集聚区范围随时间呈显著变化,景观斑块破碎化明显。(4)OPGD结果表明,土地利用类型、坡度、高程、夜间灯光为流域生态环境质量变化的主要驱动因子,人口密度、气温和GDP为次要驱动因子,降水量和坡向因子影响较小。土地利用类型与其他因子交互作用增强对流域内生态环境质量变化的影响。[结论]改进的遥感生态指数模型对开展区域生态环境质量评价提供新方法,研究结果为生态环境保护提供参考。 展开更多
关键词 生态环境质量 改进遥感生态指数模型 时空分析 驱动力 地理探测器模型 沱江流域
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基于神经网络的南方夏季蛋鸡舍环境与产蛋性能关系模型研究
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作者 谢苗苗 李华龙 《黑龙江畜牧兽医》 CAS 北大核心 2024年第9期41-47,共7页
为了解决南方地区夏季高温高湿蛋鸡舍环境质量难以精准评价与调控的问题,试验构建了基于神经网络的南方夏季蛋鸡舍环境与产蛋性能关系模型,将采集的蛋鸡舍多环境因子数据作为输入,将依据产蛋率划分的环境质量等级作为输出,对反向传播(BP... 为了解决南方地区夏季高温高湿蛋鸡舍环境质量难以精准评价与调控的问题,试验构建了基于神经网络的南方夏季蛋鸡舍环境与产蛋性能关系模型,将采集的蛋鸡舍多环境因子数据作为输入,将依据产蛋率划分的环境质量等级作为输出,对反向传播(BP)神经网络、径向基(RBF)神经网络和广义回归(GRNN)神经网络三种神经网络进行训练验证,得到蛋鸡舍环境质量初步评价结果,然后将归一化后神经网络组的输出作为改进D-S证据理论基本概率分配的输入,利用改进的D-S证据理论方法,融合计算得到蛋鸡舍环境质量的综合评价结果。结果表明:在神经网络初级融合评价有冲突的情况下,改进的D-S证据理论法对蛋鸡舍环境状态为差的支持率为0.796 4,而传统D-S证据理论方法、Murphy方法和邓勇方法对蛋鸡舍环境状态为差的支持率分别为0.698 7,0.687 8,0.694 0。说明试验构建的综合评价模型对蛋鸡舍环境的融合评价精度和准确率更高,可以有效解决融合决策失误问题,可用于南方夏季高温高湿蛋鸡舍环境的精准调控。 展开更多
关键词 多神经网络 改进的D-S证据理论 蛋鸡舍 高温高湿环境 环境评价 融合决策
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税收营商环境优化与企业对外直接投资——基于税收“放管服”改革的准自然实验
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作者 常晓素 张雨 《商学研究》 2024年第5期43-56,共14页
国内外政策环境的变化对企业对外直接投资提出了新要求。本文以税务系统“放管服”改革试点为准自然实验,基于2009—2022年沪深A股上市公司数据,运用多时点双重差分(DID),检验税收营商环境优化对企业对外直接投资的影响效应。研究发现:... 国内外政策环境的变化对企业对外直接投资提出了新要求。本文以税务系统“放管服”改革试点为准自然实验,基于2009—2022年沪深A股上市公司数据,运用多时点双重差分(DID),检验税收营商环境优化对企业对外直接投资的影响效应。研究发现:税收营商环境优化能促进企业对外直接投资,该效应在中西部地区、一般地级市、非国有企业、经营规模大、数字化水平高以及资本密集型企业中表现更为突出。机制分析表明,优化税收营商环境对企业对外直接投资的影响体现在成本效应、创新提质效应及内部治理效应三个方面。鉴于此,应深入贯彻税收“放管服”改革,通过降低企业成本、提升企业创新水平、强化企业内部治理等方式,推动企业高水平对外开放。 展开更多
关键词 税收营商环境 对外直接投资 “放管服”改革 创新提质 内部治理
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