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A practical multi-lane factor model of bridges based on multi-truck presence considering lane load disparities

《结构与土木工程前沿（英文）》 2021年 第15卷 第4期   页码 877-894 doi: 10.1007/s11709-021-0756-2

摘要： Many bridge design specifications consider multi-lane factors (MLFs) a critical component of the traffic load model. Measured multi-lane traffic data generally exhibit significant lane disparities in traffic loads over multiple lanes. However, these disparities are not considered in current specifications. To address this drawback, a multi-coefficient MLF model was developed based on an improved probabilistic statistical approach that considers the presence of multiple trucks. The proposed MLF model and approach were calibrated and demonstrated through an example site. The model sensitivity analysis demonstrated the significant influence of lane disparity of truck traffic volume and truck weight distribution on the MLF. Using the proposed approach, the experimental site study yielded MLFs comparable with those directly calculated using traffic load effects. The exclusion of overloaded trucks caused the proposed approach, existing design specifications, and conventional approach of ignoring lane load disparity to generate comparable MLFs, while the MLFs based on the proposed approach were the most comprehensive. The inclusion of overloaded trucks caused the conventional approach and design specifications to overestimate the MLFs significantly. Finally, the benefits of the research results to bridge practitioners were discussed.

关键词： bridges     multi-lane factor     traffic load     lane load disparity     multi-truck presence     weigh-in-motion data    

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一种适用于自动驾驶汽车的多层地图模型和车道级轨迹规划 Article

江昆, 杨殿阁, 柳超然, 张涛, 肖中阳

《工程（英文）》 2019年 第5卷 第2期   页码 305-318 doi: 10.1016/j.eng.2018.11.032

摘要：

越来越多的司机依赖于汽车或手机上的电子地图导航系统来选择最佳的驾驶路线，以节省时间和提高安全性，在不久的将来，电子地图和导航系统有望在未来交通运输系统中发挥更大的作用。为了将现有的导航系统扩展到更多的应用领域，如自动驾驶，需要考虑在传统道路地图模型的基础上，建立车道级地图模型和车道级轨迹规划。本研究针对传统电子地图内容不够丰富的局限性，提出了一种全新的七层自动驾驶地图结构模型，并将它命名为清华地图模型。考虑车辆换道、转向和直行等不同行车特点，建立了车道级路段行车代价模型，建立一种分层路径轨迹搜索方法，能够在道路和车道网络中实现快速的轨迹规划，能够很好地支持自动驾驶的车道级轨迹规划。通过在虚拟道路网络和实际道路网络上的测试，充分验证了该地图模型和算法的灵活性和有效性。

关键词： 车道级地图     路径规划     清华地图模型     行车代价模型    

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Investigating the role of exiting vehicles and turn indicator usage in gap acceptance at single-lane

Nathan P. BELZ

《结构与土木工程前沿（英文）》 2017年 第11卷 第1期   页码 8-16 doi: 10.1007/s11709-016-0365-7

摘要： Roundabouts are becoming a preferred form of intersection control type due to their safety and capacity benefits. Yield control at roundabout entries inherently reduces fuel consumption and emissions when compared to other conventional intersection types. However, these benefits can be limited by poor driver behavior and judgment when entering the roundabout. This research addresses the nature of gap distributions and use of turn indicators by exiting vehicles at three single-lane roundabouts in Vermont, New York, and Alaska. Presented here is a comparison of vehicle headways measured at two different locations in each roundabout. Rejected headways are analyzed in the context of priority abstaining events when entering drivers yield to vehicles exiting on the same leg of the roundabout suggesting that “true” critical gaps are being overestimated. Results indicate that exiting vehicles, particularly those that do not use their turn indicators when departing from the major-stream of traffic have an influence on the entry decision of drivers on the same approach. This behavior is of particular concern for intersection efficiency (i.e., delay) and sustainability (i.e., excess fuel consumption and emissions). Results prompt the consideration of more consistent guidance on and enforcement of turn indicator use during roundabout negotiations.

关键词： roundabouts     exiting vehicles     turn indicator use     headways    

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一种基于多因素分析和多模型集成的海洋溶解氧浓度时间序列预测混合神经网络模型 Article

刘辉, 杨睿, 段铸, 吴海平

《工程（英文）》 2021年 第7卷 第12期   页码 1751-1765 doi: 10.1016/j.eng.2020.10.023

摘要：

溶解氧是水产养殖的重要指标，准确预测溶解氧浓度可有效提高水产品质量。本文提出了一种新的溶解氧混合预测模型，该模型包括多因素分析、自适应分解和优化集成三个阶段。首先，考虑到影响溶解氧浓度的因素复杂繁多，采用灰色关联度法筛选出与溶解氧关系最密切的环境因素，多因素的考虑使得模型融合更加有效。其次，运用经验小波变换方法自适应地将溶解氧、水温、盐度和氧饱和度等序列分解为子序列。然后，利用5个基准模型对经验小波变换分解出的子序列进行预测，这五个子预测模型的集成权重通过粒子群优化和引力搜索算法计算得出。最后，通过加权分配得到溶解氧多因素集成模型。来自太平洋岛屿海洋观测系统希洛WQB04站收集的时间序列数据验证了该模型的性能。实验的评价指标包括Nash-Sutcliffe效率系数、Kling-Gupta效率系数、平均绝对百分比误差、误差标准差和决定系数。实例分析表明：①所提出的模型能够获得优异的溶解氧预测结果；②该模型优于文中其他对比模型；③预测模型可用于分析溶解氧变化趋势，便于管理者能够做出更好的决策。

关键词： 溶解氧浓度预测     时间序列多步预测     多因素分析     经验小波变化分解     多模型优化集成    

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车路集成环境下BRT专用道时分复用的车路协作方法研究

董红召,凌越,刘冬旭,郭明飞

《中国工程科学》 2012年 第14卷 第7期   页码 68-73

摘要：

为了提高BRT(bus rapid transit)专用道的利用率，基于车辆道路信息集成及协作技术，提出BRT专用道路权时分复用的车路协作方法，建立了BRT专用道时分复用的车路协作控制策略模型。研究了分段式BRT行程时间预测算法，结合实时交通流信息，建立车辆借还BRT专用道的换道时间模型，规划了车辆借还协作时序。实验表明，车辆协作控制策略中行程时间预测和借还时间估计接近实际值，并能够有效地实现专用道的时分复用，而不干扰BRT的优先运行。

关键词： 车路集成环境     车辆协作     BRT专用道     时分复用     换道时间模型    

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A multi-objective design method for seismic retrofitting of existing reinforced concrete frames using

Yue CHEN; Rong XU; Hao WU; Tao SHENG

《结构与土木工程前沿（英文）》 2022年 第16卷 第9期   页码 1089-1103 doi: 10.1007/s11709-022-0851-z

摘要： Over the past several decades, a variety of technical ways have been developed in seismic retrofitting of existing reinforced concrete frames (RFs). Among them, pin-supported rocking walls (PWs) have received much attentions to researchers recently. However, it is still a challenge that how to determine the stiffness demand of PWs and assign the value of the drift concentration factor (DCF) for entire systems rationally and efficiently. In this paper, a design method has been exploited for seismic retrofitting of existing RFs using PWs (RF-PWs) via a multi-objective evolutionary algorithm. Then, the method has been investigated and verified through a practical project. Finally, a parametric analysis was executed to exhibit the strengths and working mechanism of the multi-objective design method. To sum up, the findings of this investigation show that the method furnished in this paper is feasible, functional and can provide adequate information for determining the stiffness demand and the value of the DCF for PWs. Furthermore, it can be applied for the preliminary design of these kinds of structures.

关键词： pin-supported rocking wall     reinforced concrete frame     seismic retrofit     stiffness demand     drift concentration factor     multi-objective design     genetic algorithm     Pareto optimal solution    

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Role of the forkhead transcription factor FOXO-FOXM1 axis in cancer and drug resistance

null

《医学前沿（英文）》 2012年 第6卷 第4期   页码 376-380 doi: 10.1007/s11684-012-0228-0

摘要：

The forkhead transcription factors FOXO and FOXM1 have pivotal roles in tumorigenesis and in mediating chemotherapy sensitivity and resistance. Recent research shows that the forkhead transcription factor FOXM1 is a direct transcriptional target repressed by the forkhead protein FOXO3a, a vital downstream effector of the PI3K-AKT-FOXO signaling pathway. Intriguingly, FOXM1 and FOXO3a also compete for binding to the same gene targets, which have a role in chemotherapeutic drug action and sensitivity. An understanding of the role and regulation of the FOXO-FOXM1 axis will impact directly on our knowledge of chemotherapeutic drug action and resistance in patients, and provide new insights into the design of novel therapeutic strategy and reliable biomarkers for prediction of drug sensitivity.

关键词： FOXO3a     FOXM1     transcription factor     cancer     drug resistance     tumorigenesis    

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LSSVM-based approach for refining soil failure criteria and calculating safety factor of slopes

Shiguo XIAO; Shaohong LI

《结构与土木工程前沿（英文）》 2022年 第16卷 第7期   页码 871-881 doi: 10.1007/s11709-022-0863-8

摘要： The failure criteria of practical soil mass are very complex, and have significant influence on the safety factor of slope stability. The Coulomb strength criterion and the power-law failure criterion are classically simplified. Each one has limited applicability owing to the noticeable difference between calculated predictions and actual results in some cases. In the work reported here, an analysis method based on the least square support vector machine (LSSVM), a machine learning model, is purposefully provided to establish a complex nonlinear failure criterion via iteration computation based on strength test data of the soil, which is of more extensive applicability to many problems of slope stability. In particular, three evaluation indexes including coefficient of determination, mean absolute percentage error, and mean square error indicate that fitting precision of the machine learning-based failure criterion is better than those of the linear Coulomb criterion and nonlinear power-law criterion. Based on the proposed LSSVM approach to determine the failure criterion, the limit equilibrium method can be used to calculate the safety factor of three-dimensional slope stability. Analysis of results of the safety factor of two three-dimensional homogeneous slopes shows that the maximum relative errors between the proposed approach and the linear failure criterion-based method and the power-law failure criterion-based method are about 12% and 7%, respectively.

关键词： slope stability     safety factor     failure criterion     least square support vector machine    

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lncR-GAS5 upregulates the splicing factor to impair endothelial autophagy, leading to atherogenesis

《医学前沿（英文）》 2023年 第17卷 第2期   页码 317-329 doi: 10.1007/s11684-022-0931-4

摘要： Long noncoding RNAs (lncRNAs) play a critical role in the regulation of atherosclerosis. Here, we investigated the role of the lncRNA growth arrest-specific 5 (lncR-GAS5) in atherogenesis. We found that the enforced expression of lncR-GAS5 contributed to the development of atherosclerosis, which presented as increased plaque size and reduced collagen content. Moreover, impaired autophagy was observed, as shown by a decreased LC3II/LC3I protein ratio and an elevated P62 level in lncR-GAS5-overexpressing human aortic endothelial cells. By contrast, lncR-GAS5 knockdown promoted autophagy. Moreover, serine/arginine-rich splicing factor 10 (SRSF10) knockdown increased the LC3II/LC3I ratio and decreased the P62 level, thus enhancing the formation of autophagic vacuoles, autolysosomes, and autophagosomes. Mechanistically, lncR-GAS5 regulated the downstream splicing factor SRSF10 to impair autophagy in the endothelium, which was reversed by the knockdown of SRSF10. Further results revealed that overexpression of the lncR-GAS5-targeted gene miR-193-5p promoted autophagy and autophagic vacuole accumulation by repressing its direct target gene, SRSF10. Notably, miR-193-5p overexpression decreased plaque size and increased collagen content. Altogether, these findings demonstrate that lncR-GAS5 partially contributes to atherogenesis and plaque instability by impairing endothelial autophagy. In conclusion, lncR-GAS5 overexpression arrested endothelial autophagy through the miR-193-5p/SRSF10 signaling pathway. Thus, miR-193-5p/SRSF10 may serve as a novel treatment target for atherosclerosis.

关键词： lncR-GAS5     miR-193-5p     splicing factor SRSF10     autophagy     atherogenesis    

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The calculation of equivalence factor for ecological footprints in China: a methodological note

Moucheng LIU,Wenhua LI,Dan ZAHNG,Ning SU

《环境科学与工程前沿（英文）》 2015年 第9卷 第6期   页码 1015-1024 doi: 10.1007/s11783-014-0670-0

摘要： The Ecological Footprint (EF), a physical indicator to measure the extent of humanity’s use of natural resources, has gained much attention since it was first used by Wackernagel and Rees in 1996. In order to appraise land area types with different levels of productivity, they introduced the concept of an equivalence factor. This relates to the average primary biomass productivities of different types of land (i.e. arable land, pasture, forest, water/fishery, built-up land and fossil energy land) to the regional average primary biomass productivity of all land types in a given year. Hence, the equivalence factor is an important parameter in the EF model and it directly affects the reliability of all results. Thus, this article calculates equivalence factors on the national and provincial levels in China based on Net Primary Production (NPP) from MODIS 1 km data in 2008. Firstly, based on the Light Utility Efficiency and CASA model, the NPP of different biologically productive lands of China and of different provinces was calculated. Secondly, China’s equivalence factor for 6 land area types was calculated based on NPP: arable land and built-up land has an equivalence factor of 1.71, forest and fossil energy land has a factor of 1.41, pasture has a factor of 0.44 and water/fishery 0.35; Finally, the equivalence factor of 6 land area types in different provinces was also calculated. The NPP of each ecosystem type varies along with the equivalence factor in different provinces. However, the ranking of the equivalence factors in different provinces remain the same, with that of arable land being the largest, and the water/fishery being the smallest.

关键词： ecological footprint     equivalence factor     net primary production     biological capacity     land types    

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Numerical investigation of the influence of kinetics and shape factor on barium sulfate precipitation

Zheng WANG, Zai-Sha MAO, Chao YANG, Qinghua ZHANG, Jingcai CHENG

《化学科学与工程前沿（英文）》 2009年 第3卷 第3期   页码 272-281 doi: 10.1007/s11705-009-0023-x

摘要： The effect of kinetics and shape factor on barium sulfate precipitation in a continuous stirred tank has been investigated numerically through solving the standard momentum and mass transport equations in combination with the moment equations for crystal population balance. The numerical method was validated with the literature data. The simulated results include the distribution of the local supersaturation ratio in the reactor, the mean crystal size, and the coefficient of variation. The simulation results show that the value of shape factor used in the model affected greatly the mean crystal size and the moments of the crystal size distribution. The influence of the kinetic expressions on the simulation is also analyzed. It is important to investigate the relationship of the shape factor with the precipitator type and other operation conditions to obtain reliable simulation results and suitable kinetic equations of crystal nucleation and growth rates.

关键词： stirred tank     numerical simulation     precipitation     shape factor     crystal kinetics    

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The formation mechanism and the influence factor of residual stress in machining

null

《机械工程前沿（英文）》 2014年 第9卷 第3期   页码 265-269 doi: 10.1007/s11465-014-0311-0

摘要：

Residual stresses generated in cutting process have important influences on workpiece performance. The paper presents a method of theoretical analysis in order to explicate the formation mechanism of residual stresses in cutting. An important conclusion is drawn that the accumulated plastic strain is the main factor which determines the nature and the magnitude of surface residual stresses in the workpiece. On the basis of the analytical model for residual stress, a series of simulations for residual stress prediction during cutting AISI 1045 steel are implemented in order to obtain the influences of cutting speed, depth of cut and tool edge radius on surface residual stress in the workpiece. And these influences are explained from the perspective of formation mechanism of residual stress in cutting. The conclusions have good applicability and can be used to guide the parameters selection in actual production.

关键词： residual stress     analytical model     strain     plastic     cutting parameter    

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Endogenous tissue factor pathway inhibitor in vascular smooth muscle cells inhibits arterial thrombosis

null

《医学前沿（英文）》 2017年 第11卷 第3期   页码 403-409 doi: 10.1007/s11684-017-0522-y

摘要：

Tissue factor pathway inhibitor (TFPI) is the main inhibitor of tissue factor-mediated coagulation. TFPI is expressed by endothelial and smooth muscle cells in the vasculature. Endothelium-derived TFPI has been reported to play a regulatory role in arterial thrombosis. However, the role of endogenous TFPI in vascular smooth muscle cells (VSMCs) in thrombosis and vascular disease development has yet to be elucidated. In this TFPIFlox mice crossbred with Sma–Cre mice were utilized to establish TFPI conditional knockout mice and to examine the effects of VSMC-directed TFPI deletion on development, hemostasis, and thrombosis. The mice with deleted TFPI in VSMCs (TFPISma) reproduced viable offspring. Plasma TFPI concentration was reduced 7.2% in the TFPISma mice compared with TFPIFlox littermate controls. Plasma TFPI concentration was also detected in the TFPITie2 (mice deleted TFPI in endothelial cells and cells of hematopoietic origin) mice. Plasma TFPI concentration of the TFPITie2 mice was 80.4% lower (P<0.001) than that of the TFPIFlox mice. No difference in hemostatic measures (PT, APTT, and tail bleeding) was observed between TFPISma and TFPIFlox mice. However, TFPISma mice had increased ferric chloride–induced arterial thrombosis compared with TFPIFlox littermate controls. Taken together, these data indicated that endogenous TFPI from VSMCs inhibited ferric chloride–induced arterial thrombosis without causing hemostatic effects.

关键词： arterial thrombosis     conditional knockout mice     tissue factor pathway inhibitor     vascular smooth muscle cells    

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Fibroblast growth factor 21: a novel metabolic regulator from pharmacology to physiology

null

《医学前沿（英文）》 2013年 第7卷 第1期   页码 25-30 doi: 10.1007/s11684-013-0244-8

摘要：

Fibroblast growth factor 21 (FGF21) is a member of the fibroblast growth factor family. It actually functions as endocrine hormones but does not regulate cell growth and differentiation. It is demonstrated that FGF21 acts on multiple tissue to coordinate carbohydrate and lipid metabolism, including enhancing insulin sensitivity, decreasing triglyceride concentrations, causing weight loss, ameliorating obesity-associated hyperglycemia and hyperlipidemia. Moreover, FGF21 also plays important roles in some physiological processes, such as fasting and feeding, growth hormone axis and thermogenic function of brown adipose tissue. Clinical relevance of FGF21 in humans is still unclear, and the basis and consequences of increased FGF21 in metabolic disease remain to be determined. Both the pharmacological actions and physiological roles make FGF21 attractive drug candidates for treating metabolic disease, but some questions remain to be answered. This article concentrates on recent advances in our understanding of FGF21.

关键词： FGF21     metabolism     pharmacology     physiology     clinical relevance    

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Optimized human factor IX expression cassettes for hepatic-directed gene therapy of hemophilia B

null

《医学前沿（英文）》 2015年 第9卷 第1期   页码 90-99 doi: 10.1007/s11684-015-0390-2

摘要：

Gene therapy provides a potential cure for hemophilia B, and significant progress has been achieved in liver-directed gene transfer mediated by adeno-associated viral vectors. Recent clinical trials involving the use of a self-complementary adeno-associated virus serotype 8-human codon-optimized factor IX (AAV8-hFIXco) vector demonstrated encouraging efficacy with hFIX expression stabilized at 1% to 6% of normal level in patients, but safety concerns related to high vector doses are still present. Thus, further improvement of AAV vectors and hFIX expression cassette may positively contribute to the ultimate success of hemophilia B gene therapy. In this study, to obtain a higher expression level of hFIX that potentiates the coagulant capacity of recipients, human FIX expression vector was optimized by upgrading the codon adaption index and adjusting the GC content, inserting a Kozak sequence (GCCACC), and introducing a gain-of-function mutation, R338L (FIX Padua). The efficiency of the published and the presently constructed cassettes was compared through in vivo screening. In addition, the regulatory elements that control the FIX gene expression in these cassettes were screened for liver-specific effectiveness. Among all the constructed cassettes, scAAV-Pre-hFIXco-SIH-R338L, which was the construct under the control of the prothrombin enhancer and prealbumin promoter, resulted in the highest level of coagulant activity, and the expression levels of two constructed cassettes (scAAV-Chi-hFIXco-SIH-R338L and scAAV-Pre-hFIXco-SIH-R338L) were also higher than that of the published cassette (scAAV-LP1-hFIXco-SJ). In summary, our strategies led to a substantial increase in hFIX expression at the protein level or a remarkably elevated coagulant activity. Thus, these reconstructs of hFIX with AAV vector may potentially contribute to the creation of an efficacious gene therapy of hemophilia B.

关键词： factor IX     hemophilia B     liver-specific regulatory elements     hydrodynamic gene transfer    

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标题 作者 时间 类型 操作

A practical multi-lane factor model of bridges based on multi-truck presence considering lane load disparities

期刊论文

一种适用于自动驾驶汽车的多层地图模型和车道级轨迹规划

江昆, 杨殿阁, 柳超然, 张涛, 肖中阳

期刊论文

Investigating the role of exiting vehicles and turn indicator usage in gap acceptance at single-lane

Nathan P. BELZ

期刊论文

一种基于多因素分析和多模型集成的海洋溶解氧浓度时间序列预测混合神经网络模型

刘辉, 杨睿, 段铸, 吴海平

期刊论文

车路集成环境下BRT专用道时分复用的车路协作方法研究

董红召,凌越,刘冬旭,郭明飞

期刊论文

A multi-objective design method for seismic retrofitting of existing reinforced concrete frames using

Yue CHEN; Rong XU; Hao WU; Tao SHENG

期刊论文

Role of the forkhead transcription factor FOXO-FOXM1 axis in cancer and drug resistance

null

期刊论文

LSSVM-based approach for refining soil failure criteria and calculating safety factor of slopes

Shiguo XIAO; Shaohong LI

期刊论文

lncR-GAS5 upregulates the splicing factor to impair endothelial autophagy, leading to atherogenesis

期刊论文

The calculation of equivalence factor for ecological footprints in China: a methodological note

Moucheng LIU,Wenhua LI,Dan ZAHNG,Ning SU

期刊论文

Numerical investigation of the influence of kinetics and shape factor on barium sulfate precipitation

Zheng WANG, Zai-Sha MAO, Chao YANG, Qinghua ZHANG, Jingcai CHENG

期刊论文

The formation mechanism and the influence factor of residual stress in machining

null

期刊论文

Endogenous tissue factor pathway inhibitor in vascular smooth muscle cells inhibits arterial thrombosis

null

期刊论文

Fibroblast growth factor 21: a novel metabolic regulator from pharmacology to physiology

null

期刊论文

Optimized human factor IX expression cassettes for hepatic-directed gene therapy of hemophilia B

null

期刊论文