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Association between ICU quality and in-hospital mortality of V-V ECMO-supported patients—the ECMO quality improvement action (EQIA) study: a national cohort study in China from 2017 to 2019

《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    

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大掺量矿物掺合料高性能混凝土在京沪高铁四标段中的应用

高治双,赵年全,赵常煜,胡明文,苟云龙

《中国工程科学》 2009年 第11卷 第1期   页码 26-31

摘要：

以京沪高速铁路为工程背景，试验研究了矿物掺合料（粉煤灰、粉煤灰-矿粉）对混凝土工作性能、力学性能和耐久性能的影响以及大掺量矿物掺合料高性能混凝土的配制技术。结合实际工程，介绍了大掺量矿物掺合料高性能混凝土原材料选择、配合比设计、施工工艺等方面的控制技术。

关键词： 矿物掺合料     大掺量矿物掺合料高性能混凝土     配制与施工     质量控制    

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Modeling limit force capacities of high force to volume lead extrusion dampers

《结构与土木工程前沿（英文）》 2021年 第15卷 第3期   页码 609-622 doi: 10.1007/s11709-021-0724-x

摘要： Lead extrusion dampers are supplemental energy-dissipation devices that are used to mitigate seismic structural damage. Small volumetric sizes and high force capacities define high-force-to-volume (HF2V) devices, which can absorb significant response energy without sacrificial damage. However, the design of such devices for specific force capacities has proven difficult based on the complexities of their internal reaction mechanisms, leading to the adoption of empirical approaches. This study developed upper- and lower-bound force capacity estimates from analytical mechanics based on direct and indirect metal extrusion for guiding design. The derived equations are strictly functions of HF2V device geometric parameters, lead material properties, and extrusion mechanics. The upper-bound estimates from direct and indirect extrusion are denoted as (FUB,1, FUB,2) and (FUB,3, FUB,4), respectively, and the lower-bound estimates are denoted as (FLB, FLB,1) based on the combination of extrusion and friction forces. The proposed models were validated by comparing the predicted bounds to experimental force capacity data from 15 experimental HF2V device tests. The experimental device forces all lie above the lower-bound estimates (FLB, FLB,1) and below the upper-bound estimates (FUB,1, FUB,2, FUB,4). Overall, the (FLB, FUB,2) pair provides wider bounds and the (FLB,1, FUB,4/FUB,1) pair provides narrower bounds. The (FLB,1, FUB,1) pair has a mean lower-bound gap of 36%, meaning the lower bound was 74% of the actual device force on average. The mean upper-bound gap was 33%. The bulge area and cylinder diameter of HF2V devices are key parameters affecting device forces. These relatively tight bounds provide useful mechanics-based predictive design guides for ensuring that device forces are within the targeted design range after manufacturing.

关键词： extrusion     lead dampers     upper and lower bound     analytical modelling     limit force    

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Operation and control of flow manufacturing based on constraints management for high-mix/low-volume production

GUAN Zailin, PENG Yunfang, MA Li, ZHANG Chaoyong, LI Peigen

《机械工程前沿（英文）》 2008年 第3卷 第4期   页码 454-461 doi: 10.1007/s11465-008-0083-5

摘要： The existing technology of flow manufacturing, which is mainly appropriate for high volume and repetitive production, is proven difficult to be applied in high-mix/low-volume environments. To adapt lean production into the latter, a new type of flow manufacturing is proposed based on flow path management technology. This paper first describes the general operation framework of the proposed new mode. The main idea is the dynamic formation of adaptable virtual production lines (called flow paths) corresponding to different product families. The application of different theories of constraints/drum-buffer-rope (TOC/DBR) control policies depends on the differences in scope of variety and scale of demand for these product families. The overall architecture of the proposed mechanism of constraint management-based operation and control is introduced. For the implementation, a mathematical programming method is suggested for the dynamic planning of flow paths, and a TOC/DBR ‘path-specific’ mechanism with group scheduling is used for the control over each flow path. We also study other critical issues including the identification and management of resource bottlenecks, and the setting of the buffer size in the deployment of the TOC/DBR mechanism.

关键词： appropriate     management technology     scheduling     technology     different    

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Accelerated engineering properties of high and low volume fly ash concretes reinforced with glued steel

Vallarasu Manoharan SOUNTHARARAJAN, Dr. Anandan SIVAKUMAR

《结构与土木工程前沿（英文）》 2013年 第7卷 第4期   页码 429-445 doi: 10.1007/s11709-013-0226-6

摘要： The present study focuses on the improvement of pozzolanic reaction of fly ash particles with the cement hydration products. Low and high volume fly ash concrete mixtures were studied systematically with the addition of accelerating admixtures and accelerated curing of the concrete specimens in a steam chamber for 18 h at 75°C. Also, the reinforcing effects of glued steel fibers addition on the compressive and flexural performance of fly ash concrete were investigated. The test results indicated that the addition of accelerator improved the rate of hardening and the inclusion of steel fibers provided higher flexural performance. Also, it can be noted that the high volume fly ash (50%) addition in concrete showed a reduction in strength; however, the addition of accelerator has compensated the deceleration in strength gain. The proper selection of concrete ingredients, addition of accelerator and initial steam curing for 18 h showed better improvement on the engineering properties in fly ash concrete. A maximum increase (41.7%) in compressive strength of fly ash concrete around 52.90 MPa was noticed for 25% fly ash substitution and 1.5% steel fibers addition. Dynamic elastic modulus was also calculated in loaded concrete specimen using ultrasonic pulse velocity test and showed a good agreement with the experimental value.

关键词： fly ash     pozzolanic index     steam curing     superplasticizer     accelerator     steel fibres     elastic modulus    

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Analysis of the treatment outcomes of esophageal variceal bleeding patients from multiple centers in

WANG Zhiqiang

《医学前沿（英文）》 2008年 第2卷 第2期   页码 171-173 doi: 10.1007/s11684-008-0031-0

摘要： This study aimed to investigate the treatment outcomes of esophageal variceal bleeding (EVB) in China. A total of 1087 cases were collected from 19 hospitals in 16 large and medium sized cities across China between January 1st, 2005 and January 1st, 2006. There were 313 cases (29.0%) of mild (<400 mL), 494 cases (45.8%) of moderate (400–1500 mL) and 272 cases (25.2%) of severe (>1500 mL) bleeding. Successful hemostasis was achieved in 89.8% of cases. Seven hundred and eighty-five cases were treated by medication with a hemostasis rate of 91.8%. Seventy-one cases were treated using a Sengstaken-Blakemore tube with a hemostasis rate of 54.9%. Thirty-seven cases were treated with emergency endoscopic variceal ligation with a hemostasis rate of 83.8%. Seventy-seven cases were treated with endoscopic sclerotherapy with a hemostasis rate of 94.8%. Forty-three cases were treated with emergency surgical operation with a hemostasis rate of 95.3%. Sixty-six cases were treated with combined therapy with a hemostasis rate of 97.0%. There was a significant difference ( < 0.01) in the successful hemostasis rate between different treatments. The overall mortality was 10.1%, among which 6.6% was directly caused by bleeding. The multivariate logistic regression analysis shows that the severity of bleeding, treatment methods, liver dysfunction and activation of hepatitis were predictive factors for successful hemostasis. Most cases of EVB were mild and moderate in severity. The first-line treatment for EVB is medication. Emergency endoscopic intervention has not been widely available yet. The overall management outcome of EVB has been improved.

关键词： significant difference     predictive     medication     first-line treatment     bleeding    

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Multi-timescale optimization scheduling of interconnected data centers based on model predictive control

《能源前沿（英文）》 doi: 10.1007/s11708-023-0912-6

摘要： With the promotion of “dual carbon” strategy, data center (DC) access to high-penetration renewable energy sources (RESs) has become a trend in the industry. However, the uncertainty of RES poses challenges to the safe and stable operation of DCs and power grids. In this paper, a multi-timescale optimal scheduling model is established for interconnected data centers (IDCs) based on model predictive control (MPC), including day-ahead optimization, intraday rolling optimization, and intraday real-time correction. The day-ahead optimization stage aims at the lowest operating cost, the rolling optimization stage aims at the lowest intraday economic cost, and the real-time correction aims at the lowest power fluctuation, eliminating the impact of prediction errors through coordinated multi-timescale optimization. The simulation results show that the economic loss is reduced by 19.6%, and the power fluctuation is decreased by 15.23%.

关键词： model predictive control     interconnected data center     multi-timescale     optimized scheduling     distributed power supply     landscape uncertainty    

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PROGRESS ON IMPROVING AGRICULTURAL NITROGEN USE EFFICIENCY: UK-CHINA VIRTUAL JOINT CENTERS ON NITROGEN

《农业科学与工程前沿（英文）》 2022年 第9卷 第3期   页码 475-489 doi: 10.15302/J-FASE-2022459

摘要：

● Virtual joint centers on N agronomy were established between UK and China.

关键词： CINAg     N-CIRCLE     nitrogen use efficiency     reactive nitrogen     sustainable production    

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Shanghai Tower

Jian GONG

《工程管理前沿（英文）》 2017年 第4卷 第1期   页码 106-109 doi: 10.15302/J-FEM-2017001

摘要： Ru-jiang Zhao,Wung Hee Moh. [J]. Front. Eng, 2016, 3(2): 147-157.

关键词： super-high-rise building     green building     integral steel platform formwork system     large volume concrete     concrete pumped for super-high building     deep and large foundation pit     combined anterograde and retrograde methods     digitalized construction technology    

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Dynamics simulation of bottom high-sediment sea water movement under waves

Xueyi YOU , Wei LIU , Houpeng XIAO ,

《结构与土木工程前沿（英文）》 2009年 第3卷 第3期   页码 312-315 doi: 10.1007/s11709-009-0037-y

摘要： The movement of bottom high-sediment sea water under water waves, especially that of the high-sediment water layer close to the sea bottom, is important to the resuspension and settlement of sediment. Supposing that the high-sediment sea water is a Newtonian fluid, based on Navier-Stokes (N-S) theory, the movement of the interfaces of air-water and water-sediment water was tracked by the volume of fluid (VOF) method. The velocity field of sediment water was simulated by considering the effect of water waves. The results show that the movement of sediment water is very different from that of sea water, which provides a solid basis for understanding the resuspension and settlement of sediment and the formation of bottom stripe, and the VOF method can trace the movement of the two interfaces simultaneously; the movement of the air-water interface has a strong effect on that of the water-sediment water interface, while the effect of the water-sediment water interface movement on the air-water interface is not obvious.

关键词： volume of fluid (VOF) method     high sediment sea water     numerical simulation     interface trace     Navier-Stokes (N-S) theory    

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Assessment of liver volume variation to evaluate liver function

null

《医学前沿（英文）》 2012年 第6卷 第4期   页码 421-427 doi: 10.1007/s11684-012-0223-5

摘要：

In order to assess the value of liver volumetry in cirrhosis and acute liver failure (ALF) patients, we explored the correlation between hepatic volume and severity of the hepatic diseases. The clinical data of 48 cirrhosis patients with 60 normal controls and 39 ALF patients were collected. Computed tomography-derived liver volume (CTLV) and body surface area (BSA) of normal controls were calculated to get a regression formula for standard liver volume (SLV) and BSA. Then CTLV and SLV of all patients were calculated and grouped by Child-Turcotte-Pugh classification for cirrhosis patients and assigned according to prognosis of ALF patients for further comparison. It turned out that the mean liver volume of the control group was 1 058±337 cm3. SLV was correlated with BSA according to the regression formula. The hepatic volume of cirrhosis patients in Child A, B level was not reduced, but in Child C level it was significantly reduced with the lowest liver volume index (CTLV/SLV). Likewise, in the death group of ALF patients, the volume index was significantly lower than that of the survival group. Based on volumetric study, we proposed an ROC (receiver operating characteristic) analysis to predict the prognosis of ALF patients that CTLV/SLV<83.9% indicates a poor prognosis. In conclusion, the CTLV/SLV ratio, which reflects liver volume variations, correlates well with the liver function and progression of cirrhosis and ALF. It is also a very useful marker for predicting the prognosis of ALF.

关键词： liver volume variation     cirrhosis     acute liver failure (ALF)    

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Destructive and non-destructive evaluation of concrete for optimum sand to aggregate volume ratio

《结构与土木工程前沿（英文）》 2021年 第15卷 第6期   页码 1400-1414 doi: 10.1007/s11709-021-0779-8

摘要： Aggregates are the biggest contributor to concrete volume and are a crucial parameter in dictating its mechanical properties. As such, a detailed experimental investigation was carried out to evaluate the effect of sand-to-aggregate volume ratio (s/a) on the mechanical properties of concrete utilizing both destructive and non-destructive testing (employing UPV (ultrasonic pulse velocity) measurements). For investigation, standard cylindrical concrete samples were made with different s/a (0.36, 0.40, 0.44, 0.48, 0.52, and 0.56), cement content (340 and 450 kg/m3), water-to-cement ratio (0.45 and 0.50), and maximum aggregate size (12 and 19 mm). The effect of these design parameters on the 7, 14, and 28 d compressive strength, tensile strength, elastic modulus, and UPV of concrete were assessed. The careful analysis demonstrates that aggregate proportions and size need to be optimized for formulating mix designs; optimum ratios of s/a were found to be 0.40 and 0.44 for the maximum aggregate size of 12 and 19 mm, respectively, irrespective of the W/C (water-to-cement) and cement content.

关键词： aggregates     non-destructive testing     sand-to-aggregate volume ratio (s/a)     maximum aggregate size (MAS)    

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Integration of molecular dynamic simulation and free volume theory for modeling membrane VOC/gas separation

Bo Chen, Yan Dai, Xuehua Ruan, Yuan Xi, Gaohong He

《化学科学与工程前沿（英文）》 2018年 第12卷 第2期   页码 296-305 doi: 10.1007/s11705-018-1701-3

摘要： Gas membrane separation process is highly unpredictable due to interacting non-ideal factors, such as composition/pressure-dependent permeabilities and real gas behavior. Although molecular dynamic (MD) simulation can mimic those complex effects, it cannot precisely predict bulk properties due to scale limitations of calculation algorithm. This work proposes a method for modeling a membrane separation process for volatile organic compounds by combining the MD simulation with the free volume theory. This method can avoid the scale-up problems of the MD method and accurately simulate the performance of membranes. Small scale MD simulation and pure gas permeation data are employed to correlate pressure-irrelevant parameters for the free volume theory; by this approach, the microscopic effects can be directly linked to bulk properties (non-ideal permeability), instead of being fitted by a statistical approach. A lab-scale hollow fiber membrane module was prepared for the model validation and evaluation. The comparison of model predictions with experimental results shows that the deviations of product purity are reduced from 10% to less than 1%, and the deviations of the permeate and residue flow rates are significantly reduced from 40% to 4%, indicating the reliability of the model. The proposed method provides an efficient tool for process engineering to simulate the membrane recovery process.

关键词： membrane vapor separation     membrane process modeling     process engineering     free volume theory     volatile organic compound    

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V-shaped substrate for surface and volume enhanced Raman spectroscopic analysis of microplastics

《环境科学与工程前沿（英文）》 2022年 第16卷 第11期 doi: 10.1007/s11783-022-1578-8

摘要：

● V-shaped substrate was obtained for SERS analysis of microplastics (diameter ≈ 1 μm).

关键词： SERS     V-shaped     AAO     Microplastic     Atmospheric aerosol    

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Development of a fan-stirred constant volume combustion chamber and turbulence measurement with PIV

《能源前沿（英文）》 2022年 第16卷 第6期   页码 973-987 doi: 10.1007/s11708-021-0762-z

摘要： A fan-stirred combustion chamber is deve-loped for spherically expanding flames, with P and T up to 10 bar and 473 K, respectively. Turbulence characteristics are estimated using particle image velocimetry (PIV) at different initial pressures (P = 0.5–5 bar), fan frequencies (ω = 0–2000 r/min), and impeller diameters (D = 100 and 114 mm). The flame propagation of methanol/air is investigated at different turbulence intensities (u′=0–1.77 m/s) and equivalence ratios (φ = 0.7–1.5). The results show that u′ is independent of P and proportional to ω, which can be up to 3.5 m/s at 2000 r/min. LT is independent of P and performs a power regression with ω approximately. The turbulent field is homogeneous and isotropic in the central region of the chamber while the inertial subrange of spatial energy spectrum is more collapsed to –5/3 law at a high ReT. Compared to laminar expanding flames, the morpho-logy of turbulent expanding flames is wrinkled and the wrinkles will be finer with the growth of turbulence intensity, consistent with the decline of the Taylor scale and the Kolmogorov scale. The determined SL in the present study is in good agreement with that of previous literature. The SL and ST of methanol/air have a non-monotonic trend with φ while peak ST is shifted to the richer side compared to SL. This indicates that the newly built turbulent combustion chamber is reliable for further experimental study.

关键词： fan-stirred combustion chamber     turbulence characteristics     particle image velocimetry (PIV)     methanol     turbulent expanding flames    

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标题 作者 时间 类型 操作

Association between ICU quality and in-hospital mortality of V-V ECMO-supported patients—the ECMO quality improvement action (EQIA) study: a national cohort study in China from 2017 to 2019

期刊论文

大掺量矿物掺合料高性能混凝土在京沪高铁四标段中的应用

高治双,赵年全,赵常煜,胡明文,苟云龙

期刊论文

Modeling limit force capacities of high force to volume lead extrusion dampers

期刊论文

Operation and control of flow manufacturing based on constraints management for high-mix/low-volume production

GUAN Zailin, PENG Yunfang, MA Li, ZHANG Chaoyong, LI Peigen

期刊论文

Accelerated engineering properties of high and low volume fly ash concretes reinforced with glued steel

Vallarasu Manoharan SOUNTHARARAJAN, Dr. Anandan SIVAKUMAR

期刊论文

Analysis of the treatment outcomes of esophageal variceal bleeding patients from multiple centers in

WANG Zhiqiang

期刊论文

Multi-timescale optimization scheduling of interconnected data centers based on model predictive control

期刊论文

PROGRESS ON IMPROVING AGRICULTURAL NITROGEN USE EFFICIENCY: UK-CHINA VIRTUAL JOINT CENTERS ON NITROGEN

期刊论文

Shanghai Tower

Jian GONG

期刊论文

Dynamics simulation of bottom high-sediment sea water movement under waves

Xueyi YOU , Wei LIU , Houpeng XIAO ,

期刊论文

Assessment of liver volume variation to evaluate liver function

null

期刊论文

Destructive and non-destructive evaluation of concrete for optimum sand to aggregate volume ratio

期刊论文

Integration of molecular dynamic simulation and free volume theory for modeling membrane VOC/gas separation

Bo Chen, Yan Dai, Xuehua Ruan, Yuan Xi, Gaohong He

期刊论文

V-shaped substrate for surface and volume enhanced Raman spectroscopic analysis of microplastics

期刊论文

Development of a fan-stirred constant volume combustion chamber and turbulence measurement with PIV

期刊论文