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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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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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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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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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Shanghai center project excavation induced ground surface movements and deformations

Guolin XU, Jiwen ZHANG, Huang LIU, Changqin REN

《结构与土木工程前沿（英文）》 2018年 第12卷 第1期   页码 26-43 doi: 10.1007/s11709-017-0439-1

摘要： Empirical data on deep urban excavations can provide designers a significant reference basis for assessing potential deformations of the deep excavations and their impact on adjacent structures. The construction of the Shanghai Center involved excavations in excess of 33-m-deep using the top-down method at a site underlain by thick deposits of marine soft clay. A retaining system was achieved by 50-m-deep diaphragm walls with six levels of struts. During construction, a comprehensive instrumentation program lasting 14 months was conducted to monitor the behaviors of this deep circular excavation. The following main items related to ground surface movements and deformations were collected: (1) walls and circumferential soils lateral movements; (2) peripheral soil deflection in layers and ground settlements; and (3) pit basal heave. The results from the field instrumentation showed that deflections of the site were strictly controlled and had no large movements that might lead to damage to the stability of the foundation pit. The field performance of another 21cylindrical excavations in top-down method were collected to compare with this case through statistical analysis. In addition, numerical analyses were conducted to compare with the observed data. The extensively monitored data are characterized and analyzed in this paper.

关键词： deep excavation     foundation pit     soft clay     top-down method     field observation     ground surface movements     ground deformations    

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Comparison of membrane fouling in ultrafiltration of down-flow and up-flow biological activated carbon

Lu Ao, Wenjun Liu, Yang Qiao, Cuiping Li, Xiaomao Wang

《环境科学与工程前沿（英文）》 2018年 第12卷 第6期 doi: 10.1007/s11783-018-1046-7

摘要：

The UF membrane fouling by down- and up-flow BAC effluents were compared.

Up-flow BAC effluent fouled the membrane faster than down-flow BAC effluent.

The combined effects dominated irreversible fouling.

The extent of fouling exacerbated by inorganic particles was higher.

关键词： Ultrafiltration     Membrane fouling     Down-flow biological activated carbon     Up-flow biological activated carbon     Particles     Polysaccharide    

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一些金属材料的称重为何升温后减轻降温后变重

范良藻

《中国工程科学》 2007年 第9卷 第11期   页码 96-96

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悬索桥施工中鞍座顶推的研究

齐东春,王昌将,沈锐利,林恰

《中国工程科学》 2010年 第12卷 第7期   页码 68-73

摘要：

对悬索桥鞍座顶推中预偏量计算控制原则、塔顶位移与塔底应力的关系、顶推量和顶推时间的确定等几个问题进行了探讨，阐明了鞍座平衡条件的合理模式及预偏量的计算方法。结合坝陵河大桥鞍座的顶推计算分析，得出超量顶推可增加顶推时间间隔，减少顶推次数，顶推后的工况是主缆抗滑移验算的不利工况等结论。

关键词： 悬索桥     鞍座顶推     鞍座平衡条件     塔顶偏位     塔底应力    

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CORRECTION to: Energy-saving operation approaches for urban rail transit systems

Ziyou GAO, Lixing YANG

《工程管理前沿（英文）》   页码 698-698 doi: 10.1007/s42524-019-0047-y

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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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下降敲入续租期权定价研究

吴云,何建敏

《中国工程科学》 2004年 第6卷 第12期   页码 47-50

摘要：

阐述了现代租赁的基本内涵和实物期权的基本原理，提出了下降敲入续租期权定价模型及其定价求解，最后给出了算例分析。

关键词： 租赁     续租     租赁期权     实物期权     下降敲入期权    

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Traditional Chinese medicine: potential approaches from modern dynamical complexity theories

null

《医学前沿（英文）》 2016年 第10卷 第1期   页码 28-32 doi: 10.1007/s11684-016-0434-2

摘要：

Despite the widespread use of traditional Chinese medicine (TCM) in clinical settings, proving its effectiveness via scientific trials is still a challenge. TCM views the human body as a complex dynamical system, and focuses on the balance of the human body, both internally and with its external environment. Such fundamental concepts require investigations using system-level quantification approaches, which are beyond conventional reductionism. Only methods that quantify dynamical complexity can bring new insights into the evaluation of TCM. In a previous article, we briefly introduced the potential value of Multiscale Entropy (MSE) analysis in TCM. This article aims to explain the existing challenges in TCM quantification, to introduce the consistency of dynamical complexity theories and TCM theories, and to inspire future system-level research on health and disease.

关键词： traditional Chinese medicine     quantification     dynamical complexity     system level     balance     modern sciences    

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标题 作者 时间 类型 操作

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

Xiangyu XU, Dawen YANG,

期刊论文

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

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

期刊论文

BUEES: a bottom-up event extraction system

Xiao DING,Bing QIN,Ting LIU

期刊论文

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

Lili QU,Tianzhu ZHANG,Wei LU

期刊论文

Shanghai center project excavation induced ground surface movements and deformations

Guolin XU, Jiwen ZHANG, Huang LIU, Changqin REN

期刊论文

Comparison of membrane fouling in ultrafiltration of down-flow and up-flow biological activated carbon

Lu Ao, Wenjun Liu, Yang Qiao, Cuiping Li, Xiaomao Wang

期刊论文

一些金属材料的称重为何升温后减轻降温后变重

范良藻

期刊论文

悬索桥施工中鞍座顶推的研究

齐东春,王昌将,沈锐利,林恰

期刊论文

CORRECTION to: Energy-saving operation approaches for urban rail transit systems

Ziyou GAO, Lixing YANG

期刊论文

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

期刊论文

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

期刊论文

Leaching toxicity characteristics of municipal solid waste incineration bottom ash

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

期刊论文

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

Chunzhong LI,

期刊论文

下降敲入续租期权定价研究

吴云,何建敏

期刊论文

Traditional Chinese medicine: potential approaches from modern dynamical complexity theories

null

期刊论文