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Two-stage stochastic programming with robust constraints for the logistics network post-disruption response strategy optimization

《工程管理前沿(英文)》 2023年 第10卷 第1期   页码 67-81 doi: 10.1007/s42524-022-0240-2

摘要: Logistics networks (LNs) are essential for the transportation and distribution of goods or services from suppliers to consumers. However, LNs with complex structures are more vulnerable to disruptions due to natural disasters and accidents. To address the LN post-disruption response strategy optimization problem, this study proposes a novel two-stage stochastic programming model with robust delivery time constraints. The proposed model jointly optimizes the new-line-opening and rerouting decisions in the face of uncertain transport demands and transportation times. To enhance the robustness of the response strategy obtained, the conditional value at risk (CVaR) criterion is utilized to reduce the operational risk, and robust constraints based on the scenario-based uncertainty sets are proposed to guarantee the delivery time requirement. An equivalent tractable mixed-integer linear programming reformulation is further derived by linearizing the CVaR objective function and dualizing the infinite number of robust constraints into finite ones. A case study based on the practical operations of the JD LN is conducted to validate the practical significance of the proposed model. A comparison with the rerouting strategy and two benchmark models demonstrates the superiority of the proposed model in terms of operational cost, delivery time, and loading rate.

关键词: logistics network design     post-disruption response strategy     two-stage stochastic programming     conditional value at risk     robust constraint    

Named entity recognition for Chinese construction documents based on conditional random field

《工程管理前沿(英文)》 2023年 第10卷 第2期   页码 237-249 doi: 10.1007/s42524-021-0179-8

摘要: Named entity recognition (NER) is essential in many natural language processing (NLP) tasks such as information extraction and document classification. A construction document usually contains critical named entities, and an effective NER method can provide a solid foundation for downstream applications to improve construction management efficiency. This study presents a NER method for Chinese construction documents based on conditional random field (CRF), including a corpus design pipeline and a CRF model. The corpus design pipeline identifies typical NER tasks in construction management, enables word-based tokenization, and controls the annotation consistency with a newly designed annotating specification. The CRF model engineers nine transformation features and seven classes of state features, covering the impacts of word position, part-of-speech (POS), and word/character states within the context. The F1-measure on a labeled construction data set is 87.9%. Furthermore, as more domain knowledge features are infused, the marginal performance improvement of including POS information will decrease, leading to a promising research direction of POS customization to improve NLP performance with limited data.

关键词: NER     NLP     Chinese language     construction document    

空间资产风险评估与控制研究

张东江 ,高智杰 ,杨志涛 ,张馨文,蓝鼎

《中国工程科学》 2024年 第26卷 第1期   页码 239-250 doi: 10.15302/J-SSCAE-2024.01.018

摘要:

空间资产是国家的重要战略资产,有效控制其所面临的各类风险将有助于推动空间资产效益最大化,提高对国家安全与发展的贡献率,推动航天强国建设。本文首先讨论了空间资产的定义与内涵,认为从狭义来讲空间资产主要包含我国所有的在轨航天器,广义来讲还包括与其相关的一些关联资产和无形资产。其次,从多个维度梳理了空间资产的潜在风险源,并划分为技术、军事和管理三大类风险,其中技术类风险包括碰撞解体、爆炸解体、载荷故障、凯斯勒效应等;军事风险包括将航天器作为武器或武器平台等风险;管理风险主要指管理制度不匹配、无形资产流失等;之后针对技术类风险初步讨论了空间资产风险量化评估方法,建立空间资产价值的量化评估模型,并简要分析可能的风险控制方法。最后,面向空间资产风险事件的处置应对问题,提出初步的风险事件分级模型及处置应对需重点考虑的几个方面,如体制机制的建立、应对预案的制定、责任主体的划分、处置行动的落实与监督等。

关键词: 空间资产;风险评估;价值模型;风险控制;风险分级    

Prognostic value of fasting glucose on the risk of heart failure and left ventricular systolic dysfunction

Hui Wang, Yang Zhang, Zhujun Shen, Ligang Fang, Zhenyu Liu, Shuyang Zhang

《医学前沿(英文)》 2021年 第15卷 第1期   页码 70-78 doi: 10.1007/s11684-020-0749-x

摘要: Recent studies have shown that acute blood glucose elevation in patients with ST-segment elevation myocardial infarction (STEMI) suggests a poor prognosis. To investigate the effect of fasting blood glucose (FBG) on the risk of heart failure (HF) and left ventricular systolic dysfunction (LVSD) in non-diabetic patients undergoing primary percutaneous coronary intervention (PCI) for acute STEMI, we retrospectively recruited consecutive non-diabetic patients who underwent primary PCI for STEMI in our hospital from February 2003 to March 2015. The patients were divided into two groups according to the FBG level. A total of 623 patients were recruited with an age of 61.3±12.9 years, of whom 514 (82.5%) were male. The HF risk (odds ratio 3.401, 95% confidence interval (CI) 2.144–5.395, <0.001) was significantly increased in patients with elevated FBG than those with normal FBG. Elevated FBG was also independently related to LVSD (β 1.513, 95%CI 1.282–1.785, <0.001) in a multiple logistics regression analysis. In conclusion, elevated FBG was independently associated with 30-day HF and LVSD risk in non-diabetic patients undergoing primary PCI for STEMI.

关键词: myocardial infarction     percutaneous coronary intervention     diabetes mellitus     fasting glucose     heart failure    

卡特里娜飓风的启示——有关海洋和水利工程的风险分析

刘德辅,庞亮,谢波涛,史宏达,逯义军

《中国工程科学》 2007年 第9卷 第10期   页码 24-29

摘要:

2005年卡特里娜(Katrina)和丽塔(Rita)飓风对美国新奥尔良市和佛罗里达东部海岸带来的灾难性破坏,验证了笔者在20世纪80年代初期提出的复合极值分布理论及其对上述海域飓风强度预测结果的正确性。以此为鉴,讨论了海岸、近海、水利和城市防灾工程中引入不确定性分析和多维联合概率理论进行风险分析的必要性。

关键词: 卡特里娜飓风     复合极值分布     多维复合极值分布     不确定性分析     海洋     风险分析    

Coupling the porous conditional moment closure with the random pore model: applications to gasification

D. N. SAULOV, C. R. CHODANKA, M. J. CLEARY, A. Y. KLIMENKO

《化学科学与工程前沿(英文)》 2012年 第6卷 第1期   页码 84-93 doi: 10.1007/s11705-011-1164-2

摘要: Gasification of coal or biomass with in situ CO capture simultaneously allows production of clean hydrogen at relatively low cost and reduced emission of CO into the atmosphere. Clearly, this technology has a great potential for a future carbon constrained economy. Therefore, the development of a comprehensive, physically-based gasifier model is important. The sub-models that describe reactive transport processes in coal particles as well as in particles of CO sorbent material are among the key sub-models, which provide a necessary input for an overall gasifier model. Both coal and sorbent are materials that have complicated pore structures. The porous conditional moment closure (PCMC) model proves to be adequate for modeling reactive transport through porous media with fixed pore structure. Consumption of coal in the heterogeneous gasification reaction, however, widens the pores and reduces the surface area available for this reaction. At the same time, formation of a carbonate layer narrows the pores in the sorbent material and reduces the reaction rate of CO sorption. In both cases the pore structures are affected. Such changes are not taken into account in the existing PCMC model. In this study, we obtain the parameters of the diffusive tracer distribution based on the pore size distribution given by the widely applied random pore model (RPM), while coupling PCMC with RPM. Such coupling allows taking into account changes in pore structure caused by heterogeneous reactions and thus improves the accuracy of these key sub-models.

关键词: gasification     CO2 capture     PCMC     RPM    

Value Engineering/Value Management Model and Application of Aerospace Projects

Wan-hua Qiu,Han-peng Zhang,Ze-Shui Xu,De-Sheng Wu

《工程管理前沿(英文)》 2015年 第2卷 第4期   页码 373-377 doi: 10.15302/J-FEM-2015056

摘要: This paper presents a new space model developed by general value engineering/value management model. The authors take the function analysis, function optimization and function realization of the development object as the basic point, to get the final optimization structure by value evaluation, so as to improve the project quality and reduce the project cost. The final case shows that the application of this model can save about 18% of the time and considerable cost of the usually planned projects under the condition of quality assurance.

关键词: aerospace project     value engineering     value optimization     value stream     design structure matrix    

Value and governance of high-speed railway

Xiaoyan LIN, Zehua ZHANG, Meng WANG

《工程管理前沿(英文)》 2017年 第4卷 第4期   页码 463-482 doi: 10.15302/J-FEM-2017054

摘要: This paper considers multiple perspectives to explore the concept of high-speed railway (HSR), rationally abstract its value formation mechanism, and quantitatively measure its actual performance. This paper analyzes the governance potential of major countries in the high-speed railway value chain and studies the feasible ways and development strategies to enhance the high-speed railway governance in China. Findings of this paper are as follows. First, the government, as the early manager of high-speed railway governance, has given way to Siemens and other integrated enterprises. Second, the high-speed railway standard output has become the core competitiveness that embodies high-speed railway. Third, the global high-speed railway market presents a hierarchical high-speed railway governance model and changes to a modular approach to governance.

关键词: high-speed railway value     communication value     high-speed railway value governance     governance path upgrade    

Higher heating value prediction of torrefaction char produced from non-woody biomass

Nitipong SOPONPONGPIPAT,Dussadeeporn SITTIKUL,Unchana SAE-UENG

《能源前沿(英文)》 2015年 第9卷 第4期   页码 461-471 doi: 10.1007/s11708-015-0377-3

摘要: The higher heating value of five types of non-woody biomass and their torrefaction char was predicted and compared with the experimental data obtained in this paper. The correlation proposed in this paper and the ones suggested by previous researches were used for prediction. For prediction using proximate analysis data, the mass fraction of fixed carbon and volatile matter had a strong effect on the higher heating value prediction of torrefaction char of non-woody biomass. The high ash fraction found in torrefied char resulted in a decrease in prediction accuracy. However, the prediction could be improved by taking into account the effect of ash fraction. The correlation developed in this paper gave a better prediction than the ones suggested by previous researches, and had an absolute average error (AAE) of 2.74% and an absolute bias error (ABE) of 0.52%. For prediction using elemental analysis data, the mass fraction of carbon, hydrogen, and oxygen had a strong effect on the higher heating value, while no relationship between the higher heating value and mass fractions of nitrogen and sulfur was discovered. The best correlation gave an AAE of 2.28% and an ABE of 1.36%.

关键词: higher heating value     correlation     biomass     proximate analysis     ultimate analysis    

知识创新随机过程最大熵模型

陈欣,和金生,董丽平

《中国工程科学》 2004年 第6卷 第12期   页码 43-46

摘要:

根据创新知识的形成受已有相关知识影响的假设,综合运用概率统计、最优化、最大熵原理构建了知识创新随机过程最大熵模型,给出了以已有知识x∈X为约束的新知识y∈Y的条件概率p(y|x)。模型具有随机性与因果性对立统一的特点。

关键词: 最大熵     知识创新     条件熵     随机过程    

基于条件模式的一种无分组并行频繁模式挖掘算法 Regular Papers-Research Articles

Zhe-jun KUANG, Hang ZHOU, Dong-dai ZHOU, Jin-peng ZHOU, Kun YANG

《信息与电子工程前沿(英文)》 2019年 第20卷 第9期   页码 1234-1245 doi: 10.1631/FITEE.1800467

摘要: 频繁项集挖掘是关联规则挖掘的主要方法。由于计算空间和性能限制,特别是当数据集剧增时,挖掘频繁项的关联需要大量时间和资源。在大数据环境下的关联数据挖掘过程中,通常采用MapReduce模型进行任务划分及并行处理,从而提高算法执行效率。为确保关联规则在任务划分和并行处理期间不被破坏,需要将内部关系数据存储在计算机空间中。与原始数据集相比,存储冗余的内部关系数据将显著增加空间的使用。研究发现,频繁模式挖掘算法的形成主要依赖于条件模式基。基于并行频繁模式(PFP)算法理论,本文提出一种无分组的PFP(NG-PFP)挖掘算法。该算法取消了分组模式,减少了子任务之间的数据冗余。实验结果表明,无分组模型在计算效率和空间利用率方面都有显著提高。

关键词: 频繁模式挖掘;并行算法;条件模式基;MapReduce;大数据    

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    

On the added value of multi-scale modeling of concrete

《结构与土木工程前沿(英文)》 2022年 第16卷 第1期   页码 1-23 doi: 10.1007/s11709-021-0790-0

摘要: This review of the added value of multi-scale modeling of concrete is based on three representative examples. The first one is concerned with the analysis of experimental data, taken from four high-dynamic tests. The structural nature of the high-dynamic strength increase can be explained by using a multi-scale model. It accounts for the microstructure of the specimens. The second example refers to multi-scale thermoelastic analysis of concrete pavements, subjected to solar heating. A sensitivity analysis with respect to the internal relative humidity (RH) of concrete has underlined the great importance of the RH for an assessment of the risk of microcracking of concrete. The third example deals with multi-scale structural analysis of a real-scale test of a segmental tunnel ring. It has turned out that multi-scale modeling of concrete enables more reliable predictions of crack opening displacements in tunnel segments than macroscopic models taken from codes of practice. Overall, it is concluded that multi-scale models have indeed a significant added value. However, its degree varies with these examples. In any case, it can be assessed by means of a comparison of the results from three sources, namely, multi-scale structural analysis, conventional structural analysis, and experiments.

关键词: experiments     multi-scale analysis     conventional structural analysis     concrete     reinforced concrete    

Observer design for induction motor: an approach based on the mean value theorem

Mohamed Yacine HAMMOUDI,Abdelkarim ALLAG,Mohamed BECHERIF,Mohamed BENBOUZID,Hamza ALLOUI

《能源前沿(英文)》 2014年 第8卷 第4期   页码 426-433 doi: 10.1007/s11708-014-0314-x

摘要: In this paper, observer design for an induction motor has been investigated. The peculiarity of this paper is the synthesis of a mono-Luenberger observer for highly coupled system. To transform the nonlinear error dynamics for the induction motor into the linear parametric varying (LPV) system, the differential mean value theorem combined with the sector nonlinearity transformation has been used. Stability conditions based on the Lyapunov function lead to solvability of a set of linear matrix inequalities. The proposed observer guarantees the global exponential convergence to zero of the estimation error. Finally, the simulation results are given to show the performance of the observer design.

关键词: observer design     differential mean value theorem (DMVT)     sector nonlinearity transformation     linear matrix inequalities (LMI)     induction motor    

The value of epigenetic markers in esophageal cancer

Xiao-Mei ZHANG, Ming-Zhou GUO,

《医学前沿(英文)》 2010年 第4卷 第4期   页码 378-384 doi: 10.1007/s11684-010-0230-3

摘要: Developing esophageal cancer is a multi-step process that begins with the accumulation of genetic and epigenetic alterations, and leads to the activation of oncogenes and the inactivation or loss of tumor suppressor genes (TSG). In addition to genetic alteration, epigenetic modifications, and in particular DNA methylation, are recognized as a common molecular alteration in human tumors. In esophageal cancer, aberrant methylation of promoter regions occurs not only in advanced cancer, but also in premalignant lesions. DNA methylation is related to survival time and sensitivity of chemoradiotherapy. This review is mainly focused on epigenetic changes in esophageal cancer and the value of early detection for patient prognosis, treatment choices, and potential targeting therapy.

关键词: epigenetics     DNA methylation     esophageal cancer     dysplasia    

标题 作者 时间 类型 操作

Two-stage stochastic programming with robust constraints for the logistics network post-disruption response strategy optimization

期刊论文

Named entity recognition for Chinese construction documents based on conditional random field

期刊论文

空间资产风险评估与控制研究

张东江 ,高智杰 ,杨志涛 ,张馨文,蓝鼎

期刊论文

Prognostic value of fasting glucose on the risk of heart failure and left ventricular systolic dysfunction

Hui Wang, Yang Zhang, Zhujun Shen, Ligang Fang, Zhenyu Liu, Shuyang Zhang

期刊论文

卡特里娜飓风的启示——有关海洋和水利工程的风险分析

刘德辅,庞亮,谢波涛,史宏达,逯义军

期刊论文

Coupling the porous conditional moment closure with the random pore model: applications to gasification

D. N. SAULOV, C. R. CHODANKA, M. J. CLEARY, A. Y. KLIMENKO

期刊论文

Value Engineering/Value Management Model and Application of Aerospace Projects

Wan-hua Qiu,Han-peng Zhang,Ze-Shui Xu,De-Sheng Wu

期刊论文

Value and governance of high-speed railway

Xiaoyan LIN, Zehua ZHANG, Meng WANG

期刊论文

Higher heating value prediction of torrefaction char produced from non-woody biomass

Nitipong SOPONPONGPIPAT,Dussadeeporn SITTIKUL,Unchana SAE-UENG

期刊论文

知识创新随机过程最大熵模型

陈欣,和金生,董丽平

期刊论文

基于条件模式的一种无分组并行频繁模式挖掘算法

Zhe-jun KUANG, Hang ZHOU, Dong-dai ZHOU, Jin-peng ZHOU, Kun YANG

期刊论文

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

null

期刊论文

On the added value of multi-scale modeling of concrete

期刊论文

Observer design for induction motor: an approach based on the mean value theorem

Mohamed Yacine HAMMOUDI,Abdelkarim ALLAG,Mohamed BECHERIF,Mohamed BENBOUZID,Hamza ALLOUI

期刊论文

The value of epigenetic markers in esophageal cancer

Xiao-Mei ZHANG, Ming-Zhou GUO,

期刊论文