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Multistage analysis method for detection of effective herb prescription from clinical data

null

《医学前沿（英文）》 2018年 第12卷 第2期   页码 206-217 doi: 10.1007/s11684-017-0525-8

摘要：

Determining effective traditional Chinese medicine (TCM) treatments for specific disease conditions or particular patient groups is a difficult issue that necessitates investigation because of the complicated personalized manifestations in real-world patients and the individualized combination therapies prescribed in clinical settings. In this study, a multistage analysis method that integrates propensity case matching, complex network analysis, and herb set enrichment analysis was proposed to identify effective herb prescriptions for particular diseases (e.g., insomnia). First, propensity case matching was applied to match clinical cases. Then, core network extraction and herb set enrichment were combined to detect core effective herb prescriptions. Effectiveness-based mutual information was used to detect strong herb–symptom relationships. This method was applied on a TCM clinical data set with 955 patients collected from well-designed observational studies. Results revealed that groups of herb prescriptions with higher effectiveness rates (76.9% vs. 42.8% for matched samples; 94.2% vs. 84.9% for all samples) compared with the original prescriptions were found. Particular patient groups with symptom manifestations were also identified to help investigate the indications of the effective herb prescriptions.

关键词： effective prescription detection     herb set enrichment analysis     core network extraction     insomnia     personalized treatment    

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Operating mechanism and set pair analysis model of a sustainable water resources system

Chaoyang DU,Jingjie YU,Huaping ZHONG,Dandan WANG

《环境科学与工程前沿（英文）》 2015年 第9卷 第2期   页码 288-297 doi: 10.1007/s11783-014-0642-4

摘要： There is no alternative to the world’s water resources, and their increasing scarcity is making it difficult to meet the world population’s water needs. This paper presents a sustainable water resources system (SWRS) and analyzes the operating mechanism that makes it possible to evaluate the status of such a system. A SWRS can be described as a complex coupling system that integrates water resources, social, economic and ecological systems into a whole. The SWRS’s operating mechanism is composed of dynamic, resistance and coordination components, and it interacts with and controls the system’s evolution process. The study introduces a new approach, set pair analysis theory, to measure the state of a SWRS, and an evaluation index system is established using the subsystems and operating mechanism of a SWRS. The evaluation index system is separated into three levels (goal level, criteria level and index level) and divides the index standard into five grades. An evaluation model of the SWRS based on set pair analysis theory is constructed, and an example of SWRS evaluation in Shanghai is presented. The connection degrees of the index in the three levels are calculated, and the connection degree of the goal index is calculated to be 0.342, which classifies the city’s SWRS condition as grade 2. The sustainable use of water resources in the region is determined to be at a relatively adequate level that meets the requirements of sustainable development.

关键词： sustainable water resources system     operating mechanism     set pair analysis model     Shanghai    

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Evidence chain-based causality identification in herb-induced liver injury: exemplification of a well-knownliver-restorative herb

null

《医学前沿（英文）》 2015年 第9卷 第4期   页码 457-467 doi: 10.1007/s11684-015-0417-8

摘要：

Herbal medicines have recently been recognized as the second most common cause of drug-induced liver injury (DILI) in the United States. However, reliable methods to identify the DILI causality of some herbs, such as Heshouwu (dried root of Polygonum multiflorum), remain lacking. In this study, a total of 12 307 inpatients with liver dysfunction and 147 literature-reported cases of Heshouwu DILI were screened. A general algorithm indicated that only 22.5% (9/40) and 30.6% (45/147) of all hospitalization and literature case reports, respectively, demonstrate the high probability of DILI causality of Heshouwu. By contrast, 95% (19/20) of all cases prospectively investigated by pharmacognosy, phytochemistry, and metabolomic tests exhibited highly probable causality, including a patient who was previously incorrectly attributed and a case that was excluded from Heshouwu causality by pharmacognostic evidence. Toxin (heavy metals, pesticides, and mycotoxins) contamination was also excluded from Heshouwu DILI causality. The objectivity of these screening methods for Heshouwu DILI diagnosis addresses safety concerns regarding stilbene-containing herbal medicines and dietary supplements.

关键词： drug-induced liver injury     pharmacognosy     metabolomics     stilbene     Polygonum multiflorum     Chinese herbal medicine    

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Impact of introducing a herb pasture area into a New Zealand sheep and beef hill country farm system:a modeling analysis

Cécile DURANTON, Cory MATTHEW

《农业科学与工程前沿（英文）》 2018年 第5卷 第1期   页码 87-97 doi: 10.15302/J-FASE-2018202

摘要： New Zealand is well known for export of meat and dairy products from low cost pastoral systems. These farm systems are continually evolving for increased efficiency, in part through the use of metabolic energy modeling tools by farmers and farm consultants to explore alternative farm system configurations and identify new efficiencies. One recent innovation is the introduction of a herb pasture area, such as plantain. We used metabolic energy modeling to quantify seasonal feed flows in two successive years in a New Zealand hill country farm system, and to analyze the impact of the introduction of an area of plantain. Models employed were a self-built Microsoft Excel spreadsheet and a commercial New Zealand farm systems modeling package, FARMAX. Herbage production, animal performance and financial results for a base farm scenario created from the average of survey data for hill farms in the southern North Island, and the same farm with 10% and 20% of the area in plantain for the years 2010–2011 and 2011–2012 were modeled. The self-built model performed similarly to the commercial model. The system configuration of the base farm stockpiles surplus autumn feed for release to animals in winter and also incorporates flexibility that confers resilience to interannual weather variation through varying dates animals are purchased or sold. The introduction of an area of plantain was predicted to increase herbage production, animal performance and financial returns. The predicted benefit was higher for the year 2010–2011 where a drought occurred in summer than for the following year with higher summer rainfall. This demonstrates the profitability of introducing a plantain area to New Zealand hill farm systems, and suggests plantain will assist to mitigate adverse effects of warmer and drier summer conditions associated with current climate change trends.

关键词： farm system configuration     herb pasture     metabolic energy budgeting     plantain     sheep and beef farming    

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Level set-based isogeometric topology optimization for maximizing fundamental eigenfrequency

Manman XU, Shuting WANG, Xianda XIE

《机械工程前沿（英文）》 2019年 第14卷 第2期   页码 222-234 doi: 10.1007/s11465-019-0534-1

摘要： Maximizing the fundamental eigenfrequency is an efficient means for vibrating structures to avoid resonance and noises. In this study, we develop an isogeometric analysis (IGA)-based level set model for the formulation and solution of topology optimization in cases with maximum eigenfrequency. The proposed method is based on a combination of level set method and IGA technique, which uses the non-uniform rational B-spline (NURBS), description of geometry, to perform analysis. The same NURBS is used for geometry representation, but also for IGA-based dynamic analysis and parameterization of the level set surface, that is, the level set function. The method is applied to topology optimization problems of maximizing the fundamental eigenfrequency for a given amount of material. A modal track method, that monitors a single target eigenmode is employed to prevent the exchange of eigenmode order number in eigenfrequency optimization. The validity and efficiency of the proposed method are illustrated by benchmark examples.

关键词： topology optimization     level set method     isogeometric analysis     eigenfrequency    

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Characteristics of plankton Hg bioaccumulations based on a global data set and the implications for aquatic

《环境科学与工程前沿（英文）》 2022年 第16卷 第3期 doi: 10.1007/s11783-021-1471-x

摘要：

• Hg bioaccumulation by phytoplankton varies among aquatic ecosystems.

关键词： Plankton     Hg bioaccumulation     Physiological characteristics     A cross-system analysis     Nutrient compositions     Global data set    

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AGRONOMIC AND ENVIRONMENTAL BENEFITS OF REINTRODUCING HERB- AND LEGUME-RICH MULTISPECIES LEYS INTO ARABLE

《农业科学与工程前沿（英文）》 2022年 第9卷 第2期   页码 245-271 doi: 10.15302/J-FASE-2021439

摘要：

Agricultural intensification and the subsequent decline of mixed farming systems has led to an increase in continuous cropping with only a few fallow or break years, undermining global soil health. Arable-ley rotations incorporating temporary pastures (leys) lasting 1–4 years may alleviate soil degradation by building soil fertility and improving soil structure. However, the majority of previous research on arable-ley rotations has utilized either grass or grass-clover leys within ungrazed systems. Multispecies leys, containing a mix of grasses, legumes, and herbs, are rapidly gaining popularity due to their promotion in agri-environment schemes and potential to deliver greater ecosystem services than conventional grass or grass-clover leys. Livestock grazing in arable-ley rotations may increase the economic resilience of these systems, despite limited research of the effects of multispecies leys on ruminant health and greenhouse gas emissions. This review aims to evaluate previous research on multispecies leys, highlighting areas for future research and the potential benefits and disbenefits on soil quality and livestock productivity. The botanical composition of multispecies leys is crucial, as legumes, deep rooted perennial plants (e.g., Onobrychis viciifolia and Cichorium intybus) and herbs (e.g., Plantago lanceolata) can increase soil carbon, improve soil structure, reduce nitrogen fertilizer requirements, and promote the recovery of soil fauna (e.g., earthworms) in degraded arable soils while delivering additional environmental benefits (e.g., biological nitrification inhibition and enteric methane reduction). Multispecies leys have the potential to deliver biologically driven regenerative agriculture, but more long-term research is needed to underpin evidence-based policy and farmer guidance.

关键词： bioactive forages / integrated crop-livestock systems / nitrogen cycling / plant secondary metabolites / soil carbon / soil quality    

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Application of random set method in a deep excavation: based on a case study in Tehran cemented alluvium

Arash SEKHAVATIAN, Asskar Janalizadeh CHOOBBASTI

《结构与土木工程前沿（英文）》 2019年 第13卷 第1期   页码 66-80 doi: 10.1007/s11709-018-0461-y

摘要： The design of high-rise buildings often necessitates ground excavation, where buildings are in close proximity to the construction, thus there is a potential for damage to these structures. This paper studies an efficient user-friendly framework for dealing with uncertainties in a deep excavation in layers of cemented coarse grained soil located in Tehran, Iran by non-deterministic Random Set (RS) method. In order to enhance the acceptability of the method among engineers, a pertinent code was written in FISH language of FLAC2D software which enables the designers to run all simulations simultaneously, without cumbersome procedure of changing input variables in every individual analysis. This could drastically decrease the computational effort and cost imposed to the project, which is of great importance especially to the owners. The results are presented in terms of probability of occurrence and most likely values of the horizontal displacement at top of the wall at every stage of construction. Moreover, a methodology for assessing the credibility of the uncertainty model is presented using a quality indicator. It was concluded that performing RS analysis before the beginning of every stage could cause great economical savings, while improving the safety of the project.

关键词： uncertainty     reliability analysis     deep excavations     random set method     finite difference method    

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Isogeometric analysis based on geometric reconstruction models

《机械工程前沿（英文）》 2021年 第16卷 第4期   页码 782-797 doi: 10.1007/s11465-021-0648-0

摘要： In isogeometric analysis (IGA), the boundary representation of computer-aided design (CAD) and the tensor-product non-uniform rational B-spline structure make the analysis of three-dimensional (3D) problems with irregular geometries difficult. In this paper, an IGA method for complex models is presented by reconstructing analysis-suitable models. The CAD model is represented by boundary polygons or point cloud and is embedded into a regular background grid, and a model reconstruction method is proposed to obtain the level set function of the approximate model, which can be directly used in IGA. Three 3D examples are used to test the proposed method, and the results demonstrate that the proposed method can deal with complex engineering parts reconstructed by boundary polygons or point clouds.

关键词： isogeometric analysis     reconstruction model     level set function     trimmed element     point cloud    

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Geometrically constrained isogeometric parameterized level-set based topology optimization via trimmed

Yingjun WANG,David J. BENSON

《机械工程前沿（英文）》 2016年 第11卷 第4期   页码 328-343 doi: 10.1007/s11465-016-0403-0

摘要：

In this paper, an approach based on the fast point-in-polygon (PIP) algorithm and trimmed elements is proposed for isogeometric topology optimization (TO) with arbitrary geometric constraints. The isogeometric parameterized level-set-based TO method, which directly uses the non-uniform rational basis splines (NURBS) for both level set function (LSF) parameterization and objective function calculation, provides higher accuracy and efficiency than previous methods. The integration of trimmed elements is completed by the efficient quadrature rule that can design the quadrature points and weights for arbitrary geometric shape. Numerical examples demonstrate the efficiency and flexibility of the method.

关键词： isogeometric analysis     topology optimization     level set method     arbitrary geometric constraint     trimmed element    

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Reliability assessment of three-dimensional bearing capacity of shallow foundation using fuzzy set theory

Rajarshi PRAMANIK, Dilip Kumar BAIDYA, Nirjhar DHANG

《结构与土木工程前沿（英文）》 2021年 第15卷 第2期   页码 478-489 doi: 10.1007/s11709-021-0698-8

摘要： The aim of this study is to investigate the applicability of reliability theory on surface square/rectangular footing against bearing capacity failure using fuzzy set theory in conjunction with the finite element method. Soil is modeled as a three-dimensional spatially varying medium, where its parameters (cohesion, friction angle, unit weight, etc.) are considered as fuzzy variables that maintain some membership functions. Soil is idealized as an elastic-perfectly plastic material obeying the Mohr–Coulomb failure criterion, where both associated and non-associated flow rules are considered in estimating the ultimate bearing capacity of the footing. The spatial variability of the soil is incorporated for both isotropic and anisotropic fields, which are determined by the values of scales of fluctuation in both the horizontal and vertical directions. A new parameter namely, limiting applied pressure at zero failure probability is proposed, and it indirectly predicts the failure probability of the footing. The effect of the coefficient of variation of the friction angle of the soil on the probability of failure is analyzed, and it is observed that the effect is significant. Furthermore, the effect of the scale of fluctuation on the probability of failure is investigated, and the necessity for considering spatial variability in the reliability analysis is well proven.

关键词： finite element method     square footing     reliability analysis     fuzzy set theory     coefficient of variation     spatial variability    

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Sensitivity analysis of torsional vibration behavior of the shafting of a turbo generator set to changes

XIE Danmei, ZHANG Hengliang, DONG Chuan, LIU Zhanhui, YANG Changzhu

《能源前沿（英文）》 2007年 第1卷 第4期   页码 483-486 doi: 10.1007/s11708-007-0072-4

摘要： Aiming at a 300 MW turbo-generator model, the sensitivity of natural torsional frequencies and modes of torsional vibration (TV) to the rotational inertia and stiffness of the turbo-generator were analyzed. Calculation results show

关键词： Calculation     MW turbo-generator     sensitivity     stiffness    

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An enhanced environmental multimedia modeling system based on fuzzy-set approach: II.

Rongrong ZHANG,Chesheng ZHAN,Xiaomeng SONG,Baolin LIU

《环境科学与工程前沿（英文）》 2015年 第9卷 第6期   页码 1025-1035 doi: 10.1007/s11783-014-0655-z

摘要： Part I of this study develops an enhanced environmental multimedia modeling system (EMMS) based on fuzzy-set approach. Once the model development is complete, the composite module and the entire modeling system need to be tested and validated to ensure that the model can simulate natural phenomena with reasonable and reliable accuracy. The developed EMMS is first tested in a complete case study. And then verification results are conducted to compare with extensively researched literature data. In the third step, the data from an experimental landfill site is used for a pilot-scale validation. The comparisons between EMMS outputs and the literature data indicate that the EMMS can perform accurate modeling simulation. The modules of EMMS could support the entire environmental multimedia modeling system. Further field-scale validation is finished. The results are satisfactory. Most of the modeling yields closely match the monitoring data collected from sites. In addition, with the aid of fuzzy-set approach, EMMS can be a reliable and powerful tool to address the complex environmental multimedia pollution problems and provide an extensive support for decision makers in managing the contaminated environmental systems.

关键词： environmental multimedia modelling system     fuzzy-set approach     application     model validation     uncertainty analysis    

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Water Diversion is Not to Blame for Phosphorus Enrichment in Taihu Lake

Zhiyuan Wang,Qiuwen Chen,Jianyun Zhang,Hanlu Yan,

《工程（英文）》 doi: 10.1016/j.eng.2023.07.007

摘要： The Water Diversion Project from the Yangtze River to Taihu Lake (WDYT) has been widely recognized as an urgent and effective engineering measure to increase water resources, ameliorate the hydrodynamics and water quality conditions, and safeguard the water supply of Taihu Basin. However, some previous studies claimed that WDYT has brought in allochthonous nutrients and should take responsibility for the dramatic increase in phosphorus loading of Taihu Lake in recent years, because Yangtze River has a higher average phosphorus concentration than Taihu Lake. To ensure correct public understanding and provide a critical response to the misconception about the source of phosphorus loading, we quantified contribution of water diversion from the Yangtze River to phosphorus loadings of Taihu Lake over the past twenty years. We reveal that WDYT only diverted 4.3% annually of total phosphorus input of Taihu Lake in the last decade and should not be responsible for the increase in phosphorus concentration and loading in Taihu Lake. We conclude that phosphorus input from the Huxi Region contribute 78% of phosphorus input of Taihu Lake and should be primarily responsible for the high phosphorus concentration of Taihu Lake. Our findings have provided constructive guidance for water resource management of Taihu Basin and phosphorus load control of the second stage of WDYT.
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标题 作者 时间 类型 操作

Multistage analysis method for detection of effective herb prescription from clinical data

null

期刊论文

Operating mechanism and set pair analysis model of a sustainable water resources system

Chaoyang DU,Jingjie YU,Huaping ZHONG,Dandan WANG

期刊论文

Evidence chain-based causality identification in herb-induced liver injury: exemplification of a well-knownliver-restorative herb

null

期刊论文

Impact of introducing a herb pasture area into a New Zealand sheep and beef hill country farm system:a modeling analysis

Cécile DURANTON, Cory MATTHEW

期刊论文

Distribution, enrichment mechanism and risk assessment for fluoride in groundwater: a case study of Mihe-Weihe

期刊论文

Level set-based isogeometric topology optimization for maximizing fundamental eigenfrequency

Manman XU, Shuting WANG, Xianda XIE

期刊论文

Characteristics of plankton Hg bioaccumulations based on a global data set and the implications for aquatic

期刊论文

AGRONOMIC AND ENVIRONMENTAL BENEFITS OF REINTRODUCING HERB- AND LEGUME-RICH MULTISPECIES LEYS INTO ARABLE

期刊论文

Application of random set method in a deep excavation: based on a case study in Tehran cemented alluvium

Arash SEKHAVATIAN, Asskar Janalizadeh CHOOBBASTI

期刊论文

Isogeometric analysis based on geometric reconstruction models

期刊论文

Geometrically constrained isogeometric parameterized level-set based topology optimization via trimmed

Yingjun WANG,David J. BENSON

期刊论文

Reliability assessment of three-dimensional bearing capacity of shallow foundation using fuzzy set theory

Rajarshi PRAMANIK, Dilip Kumar BAIDYA, Nirjhar DHANG

期刊论文

Sensitivity analysis of torsional vibration behavior of the shafting of a turbo generator set to changes

XIE Danmei, ZHANG Hengliang, DONG Chuan, LIU Zhanhui, YANG Changzhu

期刊论文

An enhanced environmental multimedia modeling system based on fuzzy-set approach: II.

Rongrong ZHANG,Chesheng ZHAN,Xiaomeng SONG,Baolin LIU

期刊论文

Water Diversion is Not to Blame for Phosphorus Enrichment in Taihu Lake

Zhiyuan Wang,Qiuwen Chen,Jianyun Zhang,Hanlu Yan,

期刊论文