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BUEES: a bottom-up event extraction system

Xiao DING,Bing QIN,Ting LIU

《信息与电子工程前沿（英文）》 2015年第16卷第7期页码 541-552 doi: 10.1631/FITEE.1400405

摘要： Traditional event extraction systems focus mainly on event type identification and event participant extraction based on pre-specified event type paradigms and manually annotated corpora. However, different domains have different event type paradigms. When transferring to a new domain, we have to build a new event type paradigm and annotate a new corpus from scratch. This kind of conventional event extraction system requires massive human effort, and hence prevents event extraction from being widely applicable. In this paper, we present BUEES, a bottom-up event extraction system, which extracts events from the web in a completely unsupervised way. The system automatically builds an event type paradigm in the input corpus, and then proceeds to extract a large number of instance patterns of these events. Subsequently, the system extracts event arguments according to these patterns. By conducting a series of experiments, we demonstrate the good performance of BUEES and compare it to a state-of-the-art Chinese event extraction system, i.e., a supervised event extraction system. Experimental results show that BUEES performs comparably (5% higher -measure in event type identification and 3% higher -measure in event argument extraction), but without any human effort.

关键词： Event extraction Unsupervised learning Bottom-up

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Analysis of catchment evapotranspiration at different scales using bottom-up and top-down approaches

Xiangyu XU, Dawen YANG,

《结构与土木工程前沿（英文）》 2010年第4卷第1期页码 65-77 doi: 10.1007/s11709-010-0002-9

摘要： Physically-based hydrological models are used to predict catchment water balance through detailed simulation of hydrological processes at small temporal and spatial scales. However, annual catchment water balance can also be easily and simply predicted using lumped conceptual model. Comparison between physically-based hydrological models and lumped conceptual models can help us understand the dominant factors on catchment water balance at different scales. In this paper, a distributed physically-based hydrological model (i.e., bottom-up approach) and a simple water-energy balance model (i.e., top-down approach) are used to predict actual evapotranspiration in nine sub-catchments, and the whole basin of the Luan River in northern China. Both simulations give very close values of annual evapotranspiration and show the same complementary relationship between actual and potential evapotranspiration at annual time scale. From the analysis at different time scales through comparison of the top-down and the bottom-up methods, it is shown that the annual catchment evapotranspiration is controlled mainly by annual precipitation and potential evapotranspiration, and the variability of soil water and vegetation becomes more important at a smaller time scale in the study areas. It is also known that the relationship between potential and actual evapotranspiration shows a highly nonlinear relationship at the annual and catchment scale but can be simplified to a linear relationship at hourly temporal and hillslope scales, which is commonly used in the physically-based hydrological models.

关键词： catchment evapotranspiration distributed hydrological model water-energy balance model top-down and bottom-up approaches

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Assessing the potential of crop residue recycling in China and technology options based on a bottom-up

Lili QU,Tianzhu ZHANG,Wei LU

《环境科学与工程前沿（英文）》 2014年第8卷第4期页码 570-579 doi: 10.1007/s11783-013-0604-2

摘要： Crop residues are an important biomass, and are significant in the sustainable development of China. This paper uses the Grey-Markov modeling approach, the cost-benefit analysis method, and the constraint optimization method to establish the potential of crop residue recycling in China (CRRC) using a bottom-up analysis. Taking 2010 as the baseline year, the CRRC model is used to determine the quantity trends of crop residue resources, simulating the recycling potential and selecting key crop residue recycling technologies for operation between 2010 and 2030. The results illustrate that the total residue output from different crops will gradually increase to 1062 million tons in 2030. The proportion of crop residue for field burning is expected to decrease as a result of guidance and support from the government. Market mechanisms are also improving the development of the crop residue recycling industry. The economic benefit of crop residue recycling is expected to be worth 132 billion CNY in 2030 according to technology structure options. Key crop residue recycling technologies preferred such as liquefaction, amination, silo, co-firing straw power and composting will account for more than 85% of the total benefits.

关键词： China crop residue recycling potential technology options

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自上而下和自下而上相结合提高大规模生态修复规划的实用性和效率——来自社会-生态系统的启示 Article

Zhaowei Ding, Hua Zheng, Jun Wang, Patrick O´Connor, Cong Li, Xiaodong Chen, Ruonan Li, Zhiyun Ouyang

《工程（英文）》 2023年第31卷第12期页码 50-58 doi: 10.1016/j.eng.2022.08.008

摘要：

Ecological restoration policies and their implementation are influenced by ecological and socioeconomic drivers. Top-down approach-based spatial planning, emphasizing hierarchical control within government structures, and without a comprehensive consideration of social–ecological interactions may result in implementation failure and low efficiency. Although many researchers have indicated the necessity to engage social–ecological interactions between stakeholders in effective planning processes, socioeconomic drivers of ecological restoration on a large scale are difficult to quantify because of data scarcity and knowledge limitations. Here, we established a new ecological restoration planning approach linking a social–ecological system framework to large-scale ecological restoration planning. The new spatial planning approach integrates bottom-up approaches targeting stakeholder interests and provides social considerations for stakeholder behavior analysis. Based on this approach, a meta-analysis is introduced to recognize key socioeconomic and social–ecological factors influencing large-scale ecological restoration implementation, and a stochastic model is constructed to analyze the impact of socioeconomic drivers on the behavior of authorities and participants on a large scale. We used the Yangtze River Basin-based Conversion of Cropland to Forest Program (CCFP), one of the largest payments for ecosystem service programs worldwide, to quantify the socioeconomic impacts of large-scale ecological restoration programs. Current CCFP planning without socioeconomic considerations failed to achieve large-scale program goals and showed low investment efficiency, with 19.71% of the implemented area reconverting to cropland after contract expiry. In contrast, spatial matching between planned and actual restoration increased from 61.55% to 81.86% when socioeconomic drivers were included. In addition, compared to that with the current CCFP implementation, the cost effectiveness of spatial planning with social considerations improved by 46.94%. Thus, spatial optimization planning that integrates both top-down and bottom-up approaches can result in more practical and effective ecological restoration than top-down approaches alone. Our new approach incorporates socioeconomic factors into large-scale ecological restoration planning with high practicality and efficiency.

关键词： Social-ecological system Ecological restoration Top-down approach Bottom-up approach

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Investigation of Cu leaching from municipal solid waste incinerator bottom ash with a comprehensive approach

Jun YAO, Wenbing LI, Fangfang XIA, Jing WANG, Chengran FANG, Dongsheng SHEN

《能源前沿（英文）》 2011年第5卷第3期页码 340-348 doi: 10.1007/s11708-010-0131-9

摘要： Municipal solid waste incinerator (MSWI) bottom ash is often reused as a secondary construction material. This study used a comprehensive approach to characterize the leaching behavior of copper (Cu) from the MSWI bottom ash. The batch titration procedure was used to determine the acid neutralizing capacity and Cu leaching as a function of pH. The sequential extraction procedure (SEP) was adopted to analyze the speciation of Cu in the MSWI bottom ash. The metal speciation equilibrium model for surface and ground water (Visual MINTEQ) was used to evaluate the equilibrium of the leachates with the relative minerals, and to determine the speciation of the aqueous Cu in the leachates. Based on the multi-analysis of the results, Cu would be significantly released from the MSWI bottom ash when it is acidic. The Cu leaching pattern was not only affected by dissolved organic carbon, it was also limited by its speciation in the MSWI bottom ash. Furthermore, almost 100% of the aqueous Cu in the leachate was bound to organic matter in basic and neutral conditions, but mostly existed as Cu in an acidic condition. These findings provide an important insight into predicting the leaching behavior of Cu from the MSWI bottom ash, as well as its impact on the environment.

关键词： MSWI bottom ash Cu leaching batch titration procedure SEP

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Characterization of chlorine and heavy metals for the potential recycling of bottom ash from municipal

Boran WU, Dongyang WANG, Xiaoli CHAI, Fumitake TAKAHASHI, Takayuki SHIMAOKA

《环境科学与工程前沿（英文）》 2016年第10卷第4期 doi: 10.1007/s11783-016-0847-9

摘要： Industrial waste mixed with MSW is the main source of heavy metal in bottom ash. Chlorine content in bottom ash is controlled both by plastic and kitchen waste. Insoluble chlorine in Chinese MSWI bottom ash exists primarily as AlOCl. Bottom ash is an inevitable by-product from municipal solid waste (MSW) incineration plants. Recycling it as additives for cement production is a promising disposal method. However, the heavy metals and chlorine are the main limiting factors because of the potential environmental risks and corrosion of cement kilns. Therefore, investigating heavy metal and chlorine characteristics of bottom ash is the significant prerequisite of its reuse in cement industries. In this study, a correlative analysis was conducted to evaluate the effect of the MSW components and collection mode on the heavy metal and chlorine characteristics in bottom ash. The chemical speciation of insoluble chlorine was also investigated by synchrotron X-ray diffraction analysis. The results showed that industrial waste was the main source of heavy metals, especially Cr and Pb, in bottom ash. The higher contents of plastics and kitchen waste lead to the higher chlorine level (0.6 wt.%–0.7 wt.%) of the bottom ash. The insoluble chlorine in the MSW incineration bottom ash existed primarily as AlOCl, which was produced under the high temperature (1250℃) in incinerators.

关键词： Bottom ash Chlorine Heavy metals Waste inputs Synchrotron X-ray diffraction AlOCl

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Leaching toxicity characteristics of municipal solid waste incineration bottom ash

Khamphe PHOUNGTHONG,Yi XIA,Hua ZHANG,Liming SHAO,Pinjing HE

《环境科学与工程前沿（英文）》 2016年第10卷第2期页码 399-411 doi: 10.1007/s11783-015-0819-5

摘要： The continuously increasing production of municipal solid waste incineration bottom ash (MSWIBA) has promoted its utilization as construction material and raised environmental concern. The physico-chemical properties and leaching behavior of MSWIBA were studied, and ecotoxicological testing using a luminescent bacterium bioassay was performed to assess the ecological pollution risks associated with its leached constituents. The MSWIBA was leached by two types of leachants, H SO /HNO and HAc solution, at different liquid to solid ratios and contact times. The concentrations of heavy metals and anions in the leachates were analyzed. Multivariate statistical analyses, including principle component analysis, Pearson's correlation analysis and hierarchical cluster analysis, were used to evaluate the contributions of the constituents to the toxicity ( ) of the MSWIBA leachate. The statistical analyses of the ecotoxicological results showed that the Ba, Cr, Cu, Pb, F and total organic carbon (TOC) concentrations were closely correlated with the value, and these substances were the main contributors to the ecotoxicity of the MSWIBA leachate. In addition, the cluster of these variables indicated similar leaching behaviors. Overall, the research demonstrated that the ecotoxicological risks resulting from MSWIBA leaching could be assessed before its utilization, which provides crucial information for the adaptation of MSWIBA as alternative materials.

关键词： Municipal solid waste incineration bottom ash alternative material leaching tests toxicity Vibrio qinghaiensis (Q67)

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Structure controlling and process scale-up in the fabrication of nanomaterials

Chunzhong LI,

《化学科学与工程前沿（英文）》 2010年第4卷第1期页码 18-25 doi: 10.1007/s11705-009-0305-3

摘要： Nanotechnology is already having a significant commercial impact, and will very certainly have a much greater impact in the future. The research on process engineering and scale-up will be very important for the commercial production and application of nanomaterials, because the properties and structure of nanomaterials are not only determined by the nucleation and growth process, but also strongly affected by the engineering properties, such as the mixing, the heat and mass transfer, and also the distribution of temperature, concentration, etc. This paper will present some research work in our laboratory on the fabrication of nanomaterials. Based on the chemical engineering principle and methods, many kinds of novel nanomaterials can be synthesized and their structure can be easily controlled through adjusting the parameters of the fluid mixing, and the distribution of temperature, residence time and concentration, etc. By using the micro-mixing, heat and mass transfer and reaction control methods, the host-guest nanocomposites have been assembled and assumed as the novel electroanalytical sensing nanobiocomposite materials. Based on the principles of chemical engineering, the manufacturing technologies for magnetic powders, calcium carbonate, and titanium dioxide have been developed for commercial-scale production, and the largest production scale has reached 15 kt/year.

关键词： scale-up significant commercial electroanalytical engineering laboratory

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Parametric study on seismic performance of self-centering reinforced concrete column with bottom-placed

《结构与土木工程前沿（英文）》页码 1145-1162 doi: 10.1007/s11709-023-0945-2

摘要： To realize seismic-resilient reinforced concrete (RC) moment-resisting frame structures, a novel self-centering RC column with a rubber layer placed at the bottom (SRRC column) is proposed herein. For the column, the longitudinal reinforcement dissipates seismic energy, the rubber layer allows the rocking of the column, and the unbonded prestressed tendon enables self-centering capacity. A refined finite element model of the SRRC column is developed, the effectiveness of which is validated based on experimental results. Results show that the SRRC column exhibits stable energy dissipation capacity and no strength degradation; additionally, it can significantly reduce permanent residual deformation and mitigate damage to concrete. Extensive parametric studies pertaining to SRRC columns have been conducted to investigate the critical factors affecting their seismic performance.

关键词： seismic resilience self-centering rubber layer flag-shaped hysteresis loop parametric study

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Working Up Green, and Living Up Green

Ji-shan He

《工程管理前沿（英文）》 2014年第1卷第1期页码 2-2 doi: 10.15302/J-FEM-2014002

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超大型陆上沉井封底施工技术

杜洪池,杨宁

《中国工程科学》 2012年第14卷第5期页码 19-22

摘要：

泰州大桥北锚碇沉井封底总方量超过30 000 m³，为目前国内立方量最大的水下封底混凝土施工工程，其施工难度大，现场组织要求高。从沉井清基、封底设备布置、封底混凝土施工工艺等方面概略介绍泰州大桥北锚碇沉井封底施工技术。

关键词：超大型陆上沉井基础沉井封底技术泰州大桥

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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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合龙段底板分层破坏抗裂设计方法研究

林海峰,张冬冬,赵启林

《中国工程科学》 2012年第14卷第5期页码 106-112

摘要：

针对悬浇预应力混凝土箱梁桥合龙段底板在合龙索张拉过程中经常发生分层破坏的现象，介绍了混凝土多种破坏准则，并从理论上指出最大拉应力准则不适用于箱梁桥合龙段的底板抗裂设计，而应该采用双向应力状态下的混凝土强度破坏准则。选取多座典型破坏桥梁与未发生破坏桥梁为研究对象，建立了桥梁结构的三维实体有限元模型，得出合龙段底板预应力管道之间的竖向应力与纵向应力，进而利用不同混凝土破坏准则分别对典型桥梁的应力状态及安全性做了预测，并与桥梁实测结果进行了对比，证明了理论分析的正确性。研究结论可为同类桥梁的抗裂设计提供参考。

关键词：桥梁工程底板有限元法破坏准则双向应力

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Jack up reliability analysis: An overview

Ahmad IDRIS, Indra Sati Hamonangan HARAHAP, Montasir Osman Ahmed ALI

《结构与土木工程前沿（英文）》 2018年第12卷第4期页码 504-514 doi: 10.1007/s11709-017-0443-5

摘要： Jack up is a mobile unit used for oil and gas exploration and production in offshore fields. On demand, the unit is moved and installed in a given location and used for a period up to 12 months before being un-installed and moved to another location. Due to its mobility and re-usability, when the unit is offered for use in a given offshore location, its suitability in terms of safe operation is evaluated in accordance with the guidelines of Site Specific Assessment (SSA) of jack up. When the unit failed safety assessment criteria, the guideline recommended that it is re-assessed by increasing the complexity of the assumptions and methods used. Reliability analysis theories are one of the frameworks recommended for the safety assessment of the units. With recent developments in uncertainty and reliability analysis of structures subject to stochastic excitation, this study aims at providing a review on the past developments in jack up reliability analysis and to identify possible future directions. The results from literature reviewed shows that failure probabilities vary significantly with analysis method used. In addition, from the variants of reliability analysis approach, the method of time dependent reliability for dynamic structures subject to stochastic excitation have not been implemented on jack ups. Consequently, suggestions were made on the areas that need further examination for improvement of the efficiency in safety assessment of the units using reliability theories.

关键词： jack up reliability analysis uncertainty analysis review of jack up

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Performance of a novel bent-up bars system not interacting with concrete

Aydin SHISHEGARAN, Mohammad Reza GHASEMI, Hesam VARAEE

《结构与土木工程前沿（英文）》 2019年第13卷第6期页码 1301-1315 doi: 10.1007/s11709-019-0552-4

摘要： Increasing the bending and shear capacities of reinforced concrete members is an interesting issue in structural engineering. In recent years, many studies have been carried out to improve capacities of reinforced concrete members such as using post and pre-tensioning, Fiber Reinforced Polymer and other techniques. This paper proposes a novel and significant technique to increase the flexural capacity of simply supported reinforced concrete beams. The proposed method uses a new reinforcement bar system having bent-up bars, covered with rubber tubes. This technique will avoid interaction of bent-up bars with concrete. They are located in the zone where compressive and tensile forces act against one another. The compressive force in the upper point of the bent-up bars is exerted to the end point of these bars located under neutral axis. Moreover, the tensile stress is decreased in reinforcements located under the neutral axis. This will cause the Reinforced Concrete (RC) beam to endure extra loading before reaching yield stress. These factors may well be considered as reasons to increase bending capacity in the new system. The laboratory work together with finite element method analysis were carried out in this investigation. Furthermore, bending capacity, ductility, strength, and cracking zone were assessed for the new proposed system and compared with the conventional model. Both the FEM simulation and the experimental test results revealed that the proposed system has significant impact in increasing the load bearing capacity and the stiffness of the RC beams. In the present study, an equation is formulated to calculate bending capacity of a new reinforcement bar system beam.

关键词： bending capacity rubber tube stress transfer bent-up bars ductility cracking