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Evaluation of ICUs and weight of quality control indicators: an exploratory study based on Chinese ICUquality data from 2015 to 2020

《医学前沿(英文)》 2023年 第17卷 第4期   页码 675-684 doi: 10.1007/s11684-022-0970-x

摘要: This study aimed to explore key quality control factors that affected the prognosis of intensive care unit (ICU) patients in Chinese mainland over six years (2015−2020). The data for this study were from 31 provincial and municipal hospitals (3425 hospital ICUs) and included 2 110 685 ICU patients, for a total of 27 607 376 ICU hospitalization days. We found that 15 initially established quality control indicators were good predictors of patient prognosis, including percentage of ICU patients out of all inpatients (%), percentage of ICU bed occupancy of total inpatient bed occupancy (%), percentage of all ICU inpatients with an APACHE II score ≥15 (%), three-hour (surviving sepsis campaign) SSC bundle compliance (%), six-hour SSC bundle compliance (%), rate of microbe detection before antibiotics (%), percentage of drug deep venous thrombosis (DVT) prophylaxis (%), percentage of unplanned endotracheal extubations (%), percentage of patients reintubated within 48 hours (%), unplanned transfers to the ICU (%), 48-h ICU readmission rate (%), ventilator associated pneumonia (VAP) (per 1000 ventilator days), catheter related blood stream infection (CRBSI) (per 1000 catheter days), catheter-associated urinary tract infections (CAUTI) (per 1000 catheter days), in-hospital mortality (%). When exploratory factor analysis was applied, the 15 indicators were divided into 6 core elements that varied in weight regarding quality evaluation: nosocomial infection management (21.35%), compliance with the Surviving Sepsis Campaign guidelines (17.97%), ICU resources (17.46%), airway management (15.53%), prevention of deep-vein thrombosis (14.07%), and severity of patient condition (13.61%). Based on the different weights of the core elements associated with the 15 indicators, we developed an integrated quality scoring system defined as F score=21.35%×nosocomial infection management + 17.97%×compliance with SSC guidelines + 17.46%×ICU resources + 15.53%×airway management + 14.07%×DVT prevention + 13.61%×severity of patient condition. This evidence-based quality scoring system will help in assessing the key elements of quality management and establish a foundation for further optimization of the quality control indicator system.

关键词: critical care medicine     quality control     evaluation     exploratory factor analysis (EFA) model    

Temporal dimension and water quality control in an emission trading scheme based on water environmental

Zhaoxing HAN, Zhenyao SHEN, Yongwei GONG, Qian HONG

《环境科学与工程前沿(英文)》 2011年 第5卷 第1期   页码 119-129 doi: 10.1007/s11783-011-0272-z

摘要: Emission trading is one of the most effective alternatives to controlling water pollution. Water environmental functional zone (WEFZ) is used to determine the water quality standard and identify the zone boundary for each river or reach. In this study, a new emission trading scheme was addressed based on WEFZ, accounting for both the temporal dimension and water quality control. A temporal factor of emission trading was proposed based on variations in the environmental capacity within a year by dividing the year into three periods, including high, normal, and low periods of environmental capacity. During each period, emission trading was implemented exclusively. A water quality-control scheme was suggested based on the water quality requirement in the water functional zone, in which the water quality at the downstream boundary of the zone was required to meet the water standard following auto-purification in the stream. Two methods of calculating water quality control are addressed for point-source pollution and non-point-source pollution. The calculated temporal dimension and water quality control were located in Dongxi River of the Daning Watershed in the Three Gorges Watershed. The high period was during June, July, and August, the normal period was during April, May, September, and October, and the low period was during January, February, March, November, and December. The results from the water quality calculation demonstrated that the discharge of point-source and non-point-source pollutions led to an excess of common contaminants at the downstream boundary of WEFZ. The temporal and spatial factors above should be incorporated into the emission trading scheme based on WEFZ.

关键词: emission trading     water functional zone     water quality control    

三峡工程质量管理的实践和探索

王家柱,徐长义

《中国工程科学》 2001年 第3卷 第10期   页码 77-81

摘要:

三峡工程是开发和治理长江的关键性骨干工程。三峡工程开工8年来,建立健全了一套比较完善的 质量保证体系,实行了全过程、全方位、分层次的质量管理,工程质量得到了有效控制,工程质量良好,满足 设计要求。文章在详细介绍三峡工程质量管理与控制的基础上,对今后工作提出了几点建议。

关键词: 三峡工程     质量管理     质量控制    

SPATIOTEMPORAL VARIATION OF WATER QUALITY AND ALGAL BIOMASS IN ERHAI LAKE AND ITS ENVIRONMENTAL MANAGEMENT

《农业科学与工程前沿(英文)》 2023年 第10卷 第4期   页码 566-578 doi: 10.15302/J-FASE-2023520

摘要:

Elucidating the spatiotemporal pattern of water quality and algal biomass is crucial for accurately tracing pollution sources and reducing the risk of algal blooms in lake systems. This study analyzed the spatiotemporal variability of water quality and algal biomass in Erhai Lake from 1994 to 2021 using water quality index (WQI), Mann-Kendall test and Sen’s slope combined methods. The potential causes of water quality deterioration and algal biomass dynamics were also elucidated. The results showed that the historical changes in the water environment of Erhai Lake mainly had three stages: satisfactory (1994‒2001), deteriorating (2002‒2010) and improving (2011‒2021). The changes in water quality and algal biomass were primarily affected by total nitrogen, total phosphorus and chemical oxygen demand in different stages. The water environment of Erhai Lake is currently improving significantly, starting in the southern area that is furthest from the sources of agricultural pollution, especially in summer and autumn. This is attributed to the implementation of control measures resulting in lower pollutant loads at particular times and places. Therefore, it is necessary to continue to promote standardized livestock farming, to strengthen rural wastewater collection and to investigate measures such as the interruption of the endogenous cycle.

关键词: Erhai Lake     control measures     water environment     water quality index (WQI)    

Toxicity-oriented water quality engineering

Shengkun Dong, Chenyue Yin, Xiaohong Chen

《环境科学与工程前沿(英文)》 2020年 第14卷 第5期 doi: 10.1007/s11783-020-1259-4

摘要: • Toxicity-oriented water quality monitoring was proposed. • Toxicity-oriented water quality engineering control was proposed. • Future issues to the proposition were discussed. The fundamental goal of water quality engineering is to ensure water safety to humans and the environment. Traditional water quality engineering consists of monitoring, evaluation, and control of key water quality parameters. This approach provides some vital insights into water quality, however, most of these parameters do not account for pollutant mixtures – a reality that terminal water users face, nor do most of these parameters have a direct connection with the human health safety of waters. This puts the real health-specific effects of targeted water pollutant monitoring and engineering control in question. To focus our attention to one of the original goals of water quality engineering – human health and environmental protection, we advocate here the toxicity-oriented water quality monitoring and control. This article presents some of our efforts toward such goal. Specifically, complementary to traditional water quality parameters, we evaluated the water toxicity using high sensitivity toxicological endpoints, and subsequently investigated the performance of some of the water treatment strategies in modulating the water toxicity. Moreover, we implemented the toxicity concept into existing water treatment design theory to facilitate toxicity-oriented water quality control designs. Suggestions for the next steps are also discussed. We hope our work will intrigue water quality scientists and engineers to improve and embrace the mixture water pollutant and toxicological evaluation and engineering control.

关键词: Water     Wastewater     Mixture     Toxicity     Monitor     Control    

Clinical data quality problems and countermeasure for real world study

null

《医学前沿(英文)》 2014年 第8卷 第3期   页码 352-357 doi: 10.1007/s11684-014-0351-1

摘要:

Real world study (RWS) has become a hotspot for clinical research. Data quality plays a vital role in research achievement and other clinical research fields. In this paper, the common quality problems in the RWS of traditional Chinese medicine are discussed, and a countermeasure is proposed.

关键词: real world study     traditional Chinese medicine     clinical and research information sharing system     data quality problem     data quality control    

Overview of the quality standard research of traditional Chinese medicine

Huimin Gao, Zhimin Wang, Yujuan Li, Zhongzhi Qian

《医学前沿(英文)》 2011年 第5卷 第2期   页码 195-202 doi: 10.1007/s11684-011-0134-x

摘要: Traditional Chinese medicine (TCM) has been widely used for the prevention and treatment of various diseases for a long time in China. Due to its proven efficacy, wide applications, and low side effect, TCM has increasingly attracted worldwide attention. However, one of the biggest challenges facing the clinical practice of TCM is the uncontrollable quality. In this review, the progress of the development and the current status of quality standard as well as new quality control techniques introduced in (2010 edition), such as liquid chromatography hyphenated mass spectrometry (LC-MS), fingerprint, quantitative analysis of multi-components by single-marker (QAMS), thin layer chromatography bio-autographic assay (TLC-BAA), and DNA molecular marker technique, are briefly overviewed.

关键词: traditional Chinese medicine     quality standard     quality control     quantitative analysis of multi-components by single-marker    

Unified power quality conditioner based on a three-level NPC inverter using fuzzy control techniques

Salim CHENNAI,M-T BENCHOUIA

《能源前沿(英文)》 2014年 第8卷 第2期   页码 221-239 doi: 10.1007/s11708-014-0317-7

摘要: This paper presents a novel and efficient control scheme for unified power quality conditioner (UPQC) based on three-level neutral point clamped (NPC) inverter using fuzzy logic techniques. The proposed UPQC is capable of mitigating source current harmonics and compensate all voltage disturbances such as voltage sags, swells, unbalances and harmonics. It is designed by the integration of series and shunt active filters (AFs) sharing a common DC bus capacitor. The DC voltage is maintained constant using proportional integral voltage controller. The synchronous reference frame (SRF) theory is used to get the reference signals for shunt active power filters (APFs) and the power reactive theory (p-q theory) for series APFs. The shunt and series APF reference signals derived from the control algorithm and sensed signals are injected in two controllers to generate switching signals. To improve the UPQC capability, fuzzy logic techniques are introduced to control the series APF. The performances of the proposed UPQC system are evaluated in terms of power factor correction, mitigation of voltage or current harmonics and all other voltage disturbances compensation using Matlab-Simulink software and SimPowerSystem toolbox. The simulation results illustrate the performance of the proposed UPQC at the common connection point of the nonlinear load to improve the power energy quality.

关键词: three-level neutral point clamped (NPC) inverter     unified power quality conditioner (UPQC)     current harmonics mitigation     fuzzy logic controller     voltage disturbance compensation     shunt active filter     series active filter     power quality energy improvement    

Scenario analysis of water pollution control in the typical peri-urban river using a coupled hydrodynamic-waterquality model

Haifeng JIA, Shuo WANG, Mingjie WEI, Yansong ZHANG

《环境科学与工程前沿(英文)》 2011年 第5卷 第2期   页码 255-265 doi: 10.1007/s11783-010-0279-x

摘要: The water quality pollution and ecological deterioration in peri-urban rivers are usually serious under rapid urbanization and economic growth. In the study, a typical peri-urban river, Nansha River, was selected as a case study to discuss the scheme of peri-urban river rehabilitation. Located in the north part of the Beijing central region, the Nansha River watershed has been designated as an ecologically friendly garden-style area with high-tech industry parks and upscale residential zones. However, the Nansha River is currently seriously contaminated by urban and rural pollutants from both nonpoint sources (NPS) and point sources (PS). In this study, the pollutant loads from point sources and nonpoint sources in the Nansha River watershed were first assessed. A coupled model, derived from the Environmental Fluid Dynamics Code and Water Quality Analysis Simulation Program, was developed to simulate the hydrodynamics and water quality in the Nansha River. According to the characteristics of the typical peri-urban river, three different PS and NPS control scenarios were designed and examined by modeling analyses. Based on the results of the scenario analysis, a river rehabilitation scheme was recommended for implementation.

关键词: peri-urban river     coupled hydrodynamic-water quality modeling     scenario analysis     river rehabilitation    

Fault tolerant control strategy for modular PWM current source inverter

《能源前沿(英文)》 2023年 第17卷 第2期   页码 228-238 doi: 10.1007/s11708-022-0852-6

摘要: In this paper, a fault-tolerant control method for an input-series output-parallel modular grid-tied pulse-width modulation (PWM) current source inverter is proposed to address the most commonly seen single symmetrical gate-commutated thyristor (SGCT) open-circuit fault problems. This method actively offsets the neutral point of the current space vector to ensure a sinusoidal output of the grid current, and it can achieve the upper limit power of the inverter under the condition of a single SGCT open-circuit fault. In addition, an active damping control method based on grid harmonic current feedback is proposed after analyzing the influence of the transformer ferromagnetic resonance caused by the neutral point offset on the power quality of the grid current. It has been demonstrated that the proposed method effectively suppresses the resonance caused by the transformer and the modified modulation, improving the grid current’s power quality.

关键词: current source converter (CSC)     fault-tolerant control     space vector modulation     active damping     resonance suppression     power quality    

Quality control based on electrode displacement and force in resistance spot welding

Chuntao JI, Lipeng DENG

《机械工程前沿(英文)》 2010年 第5卷 第4期   页码 412-417 doi: 10.1007/s11465-010-0114-x

摘要: The behaviors of electrode displacement and force during spot welding under various conditions, such as different weld currents, electrode forces, and welding times, were studied. Tests were conducted on a 170?kVA MFDC spot welder. Data were collected via a multichannel high-speed data acquisition system and were analyzed with MATLAB. Behaviors of 5182 aluminum and mild steel in spot welding were compared. Results show that nugget expansion rate does not reach zero for aluminium as it does for mild steel as nugget grew to a certain size. A linear relationship is found between the nugget size and maximum expansion that facilitates online weld quality evaluation. An electrode force peak is observed and believed relevant to the sufficient nugget size.

关键词: aluminum     electrode displacement     electrode force     nugget size     data acquisition    

控制单元水质目标管理技术及应用案例研究

雷坤,乔飞,富国,苏保林

《中国工程科学》 2013年 第15卷 第3期   页码 62-69

摘要:

在研究国内外流域水环境管理技术的基础上,提出了控制单元水质目标管理技术方法,剖析了其内涵、特征,并全面阐述了控制单元划分、控制单元水质目标核定、控制单元水环境问题诊断、控制单元水质响应特征分析、控制单元允许纳污量计算与总量分配、控制单元污染物减排方案制订、控制单元污染物总量监控与评估7项核心技术环节。在此基础上,将控制单元水质目标管理技术方法在辽河流域南沙河控制单元进行技术示范,形成完整的技术方案,为流域水环境管理提供技术支撑。

关键词: 控制单元     水质目标管理     总量分配     南沙河    

Association between ICU quality and in-hospital mortality of V-V ECMO-supported patients—the ECMO quality

《医学前沿(英文)》 doi: 10.1007/s11684-023-1014-x

摘要: This cohort study was performed to explore the influence of intensive care unit (ICU) quality on in-hospital mortality of veno-venous (V-V) extracorporeal membrane oxygenation (ECMO)-supported patients in China. The study involved all V-V ECMO-supported patients in 318 of 1700 tertiary hospitals from 2017 to 2019, using data from the National Clinical Improvement System and China National Critical Care Quality Control Center. ICU quality was assessed by quality control indicators and capacity parameters. Among the 2563 V-V ECMO-supported patients in 318 hospitals, a significant correlation was found between ECMO-related complications and prognosis. The reintubation rate within 48 hours after extubation and the total ICU mortality rate were independent risk factors for higher in-hospital mortality of V-V ECMO-supported patients (cutoff: 1.5% and 7.0%; 95% confidence interval: 1.05–1.48 and 1.04–1.45; odds ratios: 1.25 and 1.23; P = 0.012 and P = 0.015, respectively). Meanwhile, the V-V ECMO center volume was a protective factor (cutoff of ≥ 50 cases within the 3-year study period; 95% confidence interval: 0.57–0.83, odds ratio: 0.69, P = 0.0001). The subgroup analysis of 864 patients in 11 high-volume centers further strengthened these findings. Thus, ICU quality may play an important role in improving the prognosis of V-V ECMO-supported patients.

关键词: veno-venous extracorporeal membrane oxygenation     in-hospital mortality     high-volume centers     quality control     intensive care unit capacity parameters    

我国优质制造技术体系建设研究

林忠钦,奚立峰,夏唐斌,赵亦希,潘尔顺,李艳婷

《中国工程科学》 2022年 第24卷 第2期   页码 1-9 doi: 10.15302/J-SSCAE-2022.02.001

摘要:

优质制造作为支撑质量变革、增加优质供给的创新模式,是实现我国制造业高质量发展的重要依托;开展优质制造技术体系与发展策略研究,对于建设制造强国、质量强国具有积极意义。本文在深入剖析我国制造质量发展痛点的基础上,基于供给端、需求端、政府监管、质量基础设施“四位一体”框架,分析了优质制造提升的关键问题,提炼了优质制造的内涵与特征,构建了“设计 – 生产 – 运维”全流程的优质制造技术架构。研究表明,我国制造质量仍存在质量效益有待进一步提高、制造品牌国际影响力不强、产业链质量升级面临困境等痛点问题。所构建的优质制造技术体系由质量技术基础、质量共性技术、全生命周期质量管控技术、资源要素等模块组成。建议加强优质制造标准体系建设,加快推动产业链质量升级,创新质量发展体制机制,提升质量资源要素供给能力,加速新技术赋能优质制造,夯实质量技术基础。

关键词: 优质制造     高质量发展     技术体系     质量技术基础     质量共性技术     质量管控技术    

Air quality improvement in Los Angeles—Perspectives for developing cities

David D. Parrish,Jin Xu,Bart Croes,Min Shao

《环境科学与工程前沿(英文)》 2016年 第10卷 第5期 doi: 10.1007/s11783-016-0859-5

摘要: Air quality improvement in Los Angeles can inform air quality policies in developing cities. Emission control efforts, their results, costs and health benefits are briefly summarized. Today's developing cities face new challenges including regional pollution. Air quality issues in Beijing are briefly compared and contrasted with Los Angeles. Opportunities for co-benefits for climate and air quality improvement are identified. Air quality improvement in Los Angeles, California is reviewed with an emphasis on aspects that may inform air quality policy formulation in developing cities. In the mid-twentieth century the air quality in Los Angeles was degraded to an extent comparable to the worst found in developing cities today; ozone exceeded 600 ppb and annual average particulate matter <10 mm reached ~150 mg·m . Today's air quality is much better due to very effective emission controls; e.g., modern automobiles emit about 1% of the hydrocarbons and carbon monoxide emitted by vehicles of 50 years ago. An overview is given of the emission control efforts in Los Angeles and their impact on ambient concentrations of primary and secondary pollutants; the costs and health benefits of these controls are briefly summarized. Today's developing cities have new challenges that are discussed: the effects of regional pollution transport are much greater in countries with very high population densities; often very large current populations must be supplied with goods and services even while economic development and air quality concerns are addressed; and many of currently developing cities are located in or close to the tropics where photochemical processing of pollution is expected to be more rapid than at higher latitudes. The air quality issues of Beijing are briefly compared and contrasted with those of Los Angeles, and the opportunities for co-benefits for climate and air quality improvement are pointed out.

关键词: Air pollution     Ozone     Particulate matter     Control technology    

标题 作者 时间 类型 操作

Evaluation of ICUs and weight of quality control indicators: an exploratory study based on Chinese ICUquality data from 2015 to 2020

期刊论文

Temporal dimension and water quality control in an emission trading scheme based on water environmental

Zhaoxing HAN, Zhenyao SHEN, Yongwei GONG, Qian HONG

期刊论文

三峡工程质量管理的实践和探索

王家柱,徐长义

期刊论文

SPATIOTEMPORAL VARIATION OF WATER QUALITY AND ALGAL BIOMASS IN ERHAI LAKE AND ITS ENVIRONMENTAL MANAGEMENT

期刊论文

Toxicity-oriented water quality engineering

Shengkun Dong, Chenyue Yin, Xiaohong Chen

期刊论文

Clinical data quality problems and countermeasure for real world study

null

期刊论文

Overview of the quality standard research of traditional Chinese medicine

Huimin Gao, Zhimin Wang, Yujuan Li, Zhongzhi Qian

期刊论文

Unified power quality conditioner based on a three-level NPC inverter using fuzzy control techniques

Salim CHENNAI,M-T BENCHOUIA

期刊论文

Scenario analysis of water pollution control in the typical peri-urban river using a coupled hydrodynamic-waterquality model

Haifeng JIA, Shuo WANG, Mingjie WEI, Yansong ZHANG

期刊论文

Fault tolerant control strategy for modular PWM current source inverter

期刊论文

Quality control based on electrode displacement and force in resistance spot welding

Chuntao JI, Lipeng DENG

期刊论文

控制单元水质目标管理技术及应用案例研究

雷坤,乔飞,富国,苏保林

期刊论文

Association between ICU quality and in-hospital mortality of V-V ECMO-supported patients—the ECMO quality

期刊论文

我国优质制造技术体系建设研究

林忠钦,奚立峰,夏唐斌,赵亦希,潘尔顺,李艳婷

期刊论文

Air quality improvement in Los Angeles—Perspectives for developing cities

David D. Parrish,Jin Xu,Bart Croes,Min Shao

期刊论文