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Dimensionality reduction and prediction of soil consolidation coefficient using random forest coupling

Hai-Bang LY; Huong-Lan Thi VU; Lanh Si HO; Binh Thai PHAM

《结构与土木工程前沿(英文)》 2022年 第16卷 第2期   页码 224-238 doi: 10.1007/s11709-022-0812-6

摘要: The consolidation coefficient of soil (Cv) is a crucial parameter used for the design of structures leaned on soft soi. In general, the Cv is determined experimentally in the laboratory. However, the experimental tests are time-consuming as well as expensive. Therefore, researchers tried several ways to determine Cv via other simple soil parameters. In this study, we developed a hybrid model of Random Forest coupling with a Relief algorithm (RF-RL) to predict the Cv of soil. To conduct this study, a database of soil parameters collected from a case study region in Vietnam was used for modeling. The performance of the proposed models was assessed via statistical indicators, namely Coefficient of determination (R2), Root Mean Squared Error (RMSE), and Mean Absolute Error (MAE). The proposal models were constructed with four sets of soil variables, including 6, 7, 8, and 13 inputs. The results revealed that all models performed well with a high performance (R2 > 0.980). Although the RF-RL model with 13 variables has the highest prediction accuracy ( R2 = 0.9869), the difference compared with other models was negligible (i.e., R2 = 0.9824, 0.9850, 0.9825 for the cases with 6, 7, 8 inputs, respectively). Thus, it can be concluded that the hybrid model of RF-RL can be employed to predict Cv based on the basic soil parameters.

关键词: soil consolidation coefficient     machine learning     random forest     Relief    

One-dimensional consolidation of over-consolidated soil under time-dependent loading

XIE Kanghe, WANG Kun, CHEN Guohong, HU Anfeng

《结构与土木工程前沿(英文)》 2008年 第2卷 第1期   页码 67-72 doi: 10.1007/s11709-008-0009-7

摘要: The problem of one-dimensional consolidation of over-consolidated saturated soil under time-dependent loading was studied based on semi-analytical method. The relevant computer code was developed by FORTRAN programming, and one-dimensional consolidation behavior of over-consolidated soil was investigated. It is shown that, unlike this described by traditional Terzaghi’s consolidation theory, the rate of excess pore water pressure dissipation is different from that of settlement developing. The magnitude of load and that of pre-consolidation pressure as well as the loading rate has all significant influence on consolidation. With the increasing of pre-consolidation pressure and loading rate, the rate of consolidation increases correspondingly. However, an increase in load will slow down the consolidation rate.

关键词: different     FORTRAN programming     Terzaghi ’     pre-consolidation     magnitude    

Split-order consolidation optimization for online supermarkets: Process analysis and optimization models

《工程管理前沿(英文)》   页码 499-516 doi: 10.1007/s42524-022-0221-5

摘要: The large-scale online supermarket is a newly emerging online retailing mode which brings great convenience to people. Online supermarkets are characterized by having large amounts of daily orders with potentially multiple items, diverse delivery times, and a high order-split rate. Multiple shipments for one order caused by order splitting result in high cost and disturbance and a large number of discarded consumable packages at online retailers and customers, causing severe damage to the environment. Accordingly, research on split-order consolidation fulfilment is critical for the advancement of the practice and theory in the context of highly complex online retailing. This paper first analyzes the characteristics and the challenges associated with the split-order consolidation problem that online supermarket is confronting and summarizes the new operational process of split-order consolidation fulfilment. Then, a time–space network optimization model is built, and its corresponding solution algorithm is presented to solve the questions of where and when to consolidate the split orders. Finally, the computation results of the numerical experiments are provided to verify the effectiveness of the algorithm, and a sensitivity analysis of the relevant parameters is performed. This work highlights the effect of order consolidation processes and fulfilment methods on the order fulfilment decision-making for online supermarkets. The purpose of this article is to help pave the way for more effective online supermarket management and order implementation.

关键词: online supermarkets     split-order consolidation     time–space network     genetic algorithm    

A method for predicting consolidation settlements of floating column improved clayey subsoil

Jinchun CHAI, Supasit PONGSIVASATHIT,

《结构与土木工程前沿(英文)》 2010年 第4卷 第2期   页码 241-251 doi: 10.1007/s11709-010-0024-3

摘要: A method of predicting the consolidation settlement-time curve of floating soil-cement column on improved soft clayey subsoil has been proposed. The degree of the consolidation (()) of the system is calculated by the double soil-layer consolidation theory, and the methods for evaluating the equivalent hydraulic conductivity () and the coefficient of volume compressibility () of the part of the column improved layer have been proposed. The effectiveness of the method was verified by comparing predictions with the results of finite element analysis (FEA) using a unit cell model. The consolidation settlement (()) can be calculated by the method of treating a part of the column improved layer as an unimproved layer and using the corresponding average () value. By comparing the predicted results with the measurements of laboratory model tests and three case histories in Fukuoka, Japan, the effectiveness of the proposed methods has been verified. It is suggested that the method can be used for designing the soft clayey subsoil improvement using floating soil-cement columns.

关键词: cement depth mixing     ground improvement     consolidation     settlement    

syndrome and toxic epidermal necrolysis in China: evaluation of risk models and new predictor of pulmonary consolidation

Yanhong Shou, Lu Yang, Yongsheng Yang, Xiaohua Zhu, Feng Li, Bo Yin, Yingyan Zheng, Jinhua Xu

《医学前沿(英文)》 2021年 第15卷 第4期   页码 585-593 doi: 10.1007/s11684-020-0817-2

摘要: Stevens--Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are rare but severe diseases. This study aimed to validate the predictive ability of risk models in patients with SJS/TEN and propose possible refinement in China. Patients in the Department of Dermatology of Huashan Hospital from January 2008 to January 2019 were included. Results showed that the severity-of-illness score for TEN (SCORTEN) had a good discrimination (area under the receiver operating characteristic curve (AUC), 0.78), and it was superior to auxiliary score (AS) and ABCD-10, which indicates age, bicarbonate level, cancer, dialysis, and 10% involved body surface area (AUC, 0.69 and 0.68, respectively). The calibration of SCORTEN (Hosmer–Lemeshow goodness-of-fit test, = 0.69) was also better than that of AS ( = 0.25) and ABCD-10 ( = 0.55). SCORTEN and ABCD-10 were similar (Brier score (BS), 0.04 and 0.04) in terms of accuracy of predictions. In addition, the imaging appearance of pulmonary consolidation on computed tomography was associated with high mortality. Refined models were formed using the variables and this imaging appearance. The refined AS and ABCD-10 models were similar in discrimination compared with the original SCORTEN (0.74 vs. 0.78, = 0.23; 0.74 vs. 0.78, = 0.30, respectively). Therefore, SCORTEN showed good discrimination performance, calibration, and accuracy, and refined AS or ABCD-10 model may be an option when SCORTEN variables are not available.

关键词: Stevens–Johnson syndrome     toxic epidermal necrolysis     auxiliary score     ABCD-10     pulmonary consolidation    

高饱和土固结及饱和度对土体固结的影响

金志高

《中国工程科学》 2004年 第6卷 第9期   页码 73-76

摘要:

以Terzaghi土体固结理论和Biot固结理论为基础,按饱和度不同的分类,研究了高饱和土固结机理及过程,深入分析了高饱和土饱和度变化对孔隙流体压缩性的影响,以及由此影响到高饱和土的固结全过程。

关键词: 固结     饱和度     体变模量     压缩    

现代农业双优工程试验原理与方法——以毛乌素沙地为例

王永生,李玉恒,刘彦随

《中国工程科学》 2019年 第21卷 第2期   页码 48-54 doi: 10.15302/J-SSCAE-2019.02.017

摘要:

土地是人类赖以生存与发展的重要资源和物质基础,现代农业的发展依赖于健康、生态、高效的土地。消除退化土地的利用障碍,改良作物生长环境,为不同作物生长需求提供最适宜的“土地配方”,是当前面临的主要问题。针对毛乌素沙地区(榆林)沙化土地整治与可持续利用问题,利用红黏土、黄土与沙土的物理互补性,对沙化土地进行结构性整治,构建沙化土地整治土体优配和现代农业良种优选的复合技术体系,实现“沙化土地的订单式整治”,为毛乌素沙地区(榆林)退化土地整治与现代农业的耦合发展提供科技支撑。未来应重点加强土地工程链研究,创建全链式土地工程管理机制,实现微观土地复配、中观土体营造和宏观土质改良工程的技术化和标准化。

关键词: 土地整治工程     现代农业     土体重构     作物优选     毛乌素沙地    

土坡稳定分析应力状态新方法的过程解析

王国体,王婉娣

《中国工程科学》 2010年 第12卷 第1期   页码 52-55

摘要:

依据土体应力状态、计算边坡稳定安全系数的思想,结合对土体根本性质的认识,对基本假定、公式推导过程和工程应用进行了详细的说明。由于土坡稳定安全系数的计算公式在理论分析依据是严密的,推证得到的计算公式是正确的,所以在工程实用是可靠的。文章为该方法的工程应用和深入开展相关的研究奠定坚实的基础。

关键词: 土坡稳定分析方法     应力状态     稳定安全系数    

以土体应力状态计算边坡安全系数的方法

王国体

《中国工程科学》 2006年 第8卷 第12期   页码 80-84

摘要:

土坡的稳定分析一直是沿着条分法的思路发展的。由于对土体应力状态条件的忽视和条分法本身的缺陷,使得条分法得到的安全系数在工程中的应用面临激烈的挑战。土体不同条件下的应力状态表现为K0效应和变化,它对坡体的安全度影响不可忽视。笔者以考虑土体应力状态为条件,应用土的库伦强度定律和摩尔-库伦准则,推导出平面土坡的安全系数计算公式,与条分法的安全系数对比结果说明这种方法具有概念明确、计算简便、定性可靠的重要特点,可以直接提供于工程应用和参考。

关键词: 侧应力系数K0     初始应力状态     稳定安全系数公式    

RETRACTED ARTICLE: Momentum exchange coefficient for two jet flows mixing in a tee junction

《化学科学与工程前沿(英文)》 2023年 第17卷 第12期   页码 2161-2161 doi: 10.1007/s11705-009-0143-3

摘要: RETRACTED ARTICLE: Momentum exchange coefficient for two jet flows mixing in a tee junction

关键词: tee junction     Momentum exchange coefficient     RETRACTED    

横观各向同性土体三维比奥固结有限层解法

梅国雄,宰金珉,赵维炳,殷建华

《中国工程科学》 2004年 第6卷 第7期   页码 43-47

摘要:

建立了三维横观各向同性土体固结的有限层求解方法,并编制了相应的计算程序;通过2个算例的分析对比,验证了计算方法和程序的正确性;探讨了横观各向同性地基参数对三维地基固结的影响,给出了对工程有价值的相关计算图表和结论。

关键词: 有限层     比奥固结     三维     横观各向同性    

Transforming the Loess Plateau of China

Yuheng LI,Guoming DU,Yansui LIU

《农业科学与工程前沿(英文)》 2016年 第3卷 第3期   页码 181-185 doi: 10.15302/J-FASE-2016110

摘要: This paper aims to show the importance of land consolidation in transforming the Loess Plateau of China. The paper comprehensively analyzes how over recent decades the Grain for Green Project and Gully Land Consolidation Project jointly transformed the ecology and landscape of the Loess Plateau and the livelihood of its residents. The findings show that these two projects have achieved a balance between green protection, new land creation, and improved food security and livelihood of local people in the hilly areas of China. The paper points out that the successful transformation of the Plateau lies in a holistic approach incorporating various components of the human and natural systems. Finally, the paper highlights the necessity of retaining these two land consolidation projects as part of an ongoing policy in the mountain and hilly areas of China, changing agricultural management to suit the new relationship between humans and the land.

关键词: China     critical zone     land consolidation     Loess Plateau     sustainability    

Experimental study of heat transfer coefficient with rectangular baffle fin of solar air heater

Foued CHABANE,Nesrine HATRAF,Noureddine MOUMMI

《能源前沿(英文)》 2014年 第8卷 第2期   页码 160-172 doi: 10.1007/s11708-014-0321-y

摘要: This paper presents an experimental analysis of a single pass solar air collector with, and without using baffle fin. The heat transfer coefficient between the absorber plate and air can be considerably increased by using artificial roughness on the bottom plate and under the absorber plate of a solar air heater duct. An experimental study has been conducted to investigate the effect of roughness and operating parameters on heat transfer. The investigation has covered the range of Reynolds number from 1259 to 2517 depending on types of the configuration of the solar collectors. Based on the experimental data, values of Nusselt number have been determined for different values of configurations and operating parameters. To determine the enhancement in heat transfer and increment in thermal efficiency, the values of Nusselt have been compared with those of smooth duct under similar flow conditions.

关键词: Nusselt number     flow rate     heat transfer     heat transfer coefficient     thermal efficiency     forced convection    

Comparison of evapotranspiration and energy partitioning related to main biotic and abiotic controllers in vineyards using different irrigation methods

Lei GAO, Peng ZHAO, Shaozhong KANG, Sien LI, Ling TONG, Risheng DING, Hongna LU

《农业科学与工程前沿(英文)》 2020年 第7卷 第4期   页码 490-504 doi: 10.15302/J-FASE-2019310

摘要:

Knowledge of evapotranspiration (ET) and energy partitioning is useful for optimizing water management, especially in areas where water is scarce. A study was undertaken in a furrow-irrigated vineyard (2015) and a drip-irrigated vineyard (2017) in an arid region of north-west China to compare vineyard ET and energy partitioning and their responses to soil water content (SWC) and leaf area index (LAI). ET and soil evaporation (E) and transpiration (T) were determined using eddy covariance, microlysimeters, and sap flow. Seasonal average E/ET, T/ET, crop coefficient (Kc), evaporation coefficient (Ke), and basal crop coefficient (Kcb) were 0.50, 0.50, 0.67, 0.35, and 0.29, respectively, in the furrow-irrigated vineyard and 0.42, 0.58, 0.57, 0.29, and 0.43 in the drip-irrigated vineyard. The seasonal average partitioning of net radiation (Rn) into the latent heat flux (LE), sensible heat flux (H) and soil heat flux (G) (LE/Rn, H/Rn, and G/Rn), evaporative fraction (EF) and Bowen ratio (β) were 0.57, 0.26, 0.17, 0.69 and 0.63, respectively, in the furrow-irrigated vineyard and 0.46, 0.36, 0.17, 0.57 and 0.97 in the drip-irrigated vineyard. The LE/Rn, H/Rn, EF, and β were linearly correlated with LAI. The E, Kc, Ke, E/ET, LE/Rn, LEs/Rn (ratio of LE by soil E to Rn), H/Rn, EF and β were closely correlated with topsoil SWC (10 cm depth). Responses of ET and energy partitioning to the LAI and SWC differed under the two irrigation methods. Drip irrigation reduced seasonal average E/ET and increased average T/ET. From the perspective of energy partitioning, seasonal average H/Rn increased whereas LE/Rn, especially LEs/Rn, decreased. Compared with furrow irrigation, drip irrigation decreased the proportion of unproductive water consumption thereby contributing to enhanced water use efficiency and accumulation of dry matter.

关键词: crop coefficient     eddy covariance     microlysimeter     sap flow     soil evaporation     transpiration    

A photolysis coefficient for characterizing the response of aqueous constituents to photolysis

David R. HOKANSON,Ke LI,R. Rhodes TRUSSELL

《环境科学与工程前沿(英文)》 2016年 第10卷 第3期   页码 428-437 doi: 10.1007/s11783-015-0780-3

摘要: UV photolysis and UV based advanced oxidation processes (AOPs) are gaining more and more attention for drinking water treatment. Quantum yield ( ) and molar absorption coefficient ( ) are the two critical parameters measuring the effectiveness of photolysis of a compound. The product of the two was proposed as a fundamental measure of a constituent’s amenability to transformation by photolysis. It was shown that this product, named the photolysis coefficient, , can be determined using standard bench tests and captures the properties that govern a constituent’s transformation when exposed to light. The development showed the photolysis coefficient to be equally useful for microbiological, inorganic and organic constituents. Values of calculated by the authors based on quantum yield and molar absorption coefficient data from the literature were summarized. Photolysis coefficients among microorganisms ranged from 8500 to more than 600000 and are far higher than for inorganic and organic compounds, which varied over a range of approximately 10 to 1000 and are much less sensitive to UV photolysis than the microorganisms.

关键词: UV photolysis     disinfection     advanced oxidation     N-nitrosodimethylamine     quantum yield     absorption coefficient    

标题 作者 时间 类型 操作

Dimensionality reduction and prediction of soil consolidation coefficient using random forest coupling

Hai-Bang LY; Huong-Lan Thi VU; Lanh Si HO; Binh Thai PHAM

期刊论文

One-dimensional consolidation of over-consolidated soil under time-dependent loading

XIE Kanghe, WANG Kun, CHEN Guohong, HU Anfeng

期刊论文

Split-order consolidation optimization for online supermarkets: Process analysis and optimization models

期刊论文

A method for predicting consolidation settlements of floating column improved clayey subsoil

Jinchun CHAI, Supasit PONGSIVASATHIT,

期刊论文

syndrome and toxic epidermal necrolysis in China: evaluation of risk models and new predictor of pulmonary consolidation

Yanhong Shou, Lu Yang, Yongsheng Yang, Xiaohua Zhu, Feng Li, Bo Yin, Yingyan Zheng, Jinhua Xu

期刊论文

高饱和土固结及饱和度对土体固结的影响

金志高

期刊论文

现代农业双优工程试验原理与方法——以毛乌素沙地为例

王永生,李玉恒,刘彦随

期刊论文

土坡稳定分析应力状态新方法的过程解析

王国体,王婉娣

期刊论文

以土体应力状态计算边坡安全系数的方法

王国体

期刊论文

RETRACTED ARTICLE: Momentum exchange coefficient for two jet flows mixing in a tee junction

期刊论文

横观各向同性土体三维比奥固结有限层解法

梅国雄,宰金珉,赵维炳,殷建华

期刊论文

Transforming the Loess Plateau of China

Yuheng LI,Guoming DU,Yansui LIU

期刊论文

Experimental study of heat transfer coefficient with rectangular baffle fin of solar air heater

Foued CHABANE,Nesrine HATRAF,Noureddine MOUMMI

期刊论文

Comparison of evapotranspiration and energy partitioning related to main biotic and abiotic controllers in vineyards using different irrigation methods

Lei GAO, Peng ZHAO, Shaozhong KANG, Sien LI, Ling TONG, Risheng DING, Hongna LU

期刊论文

A photolysis coefficient for characterizing the response of aqueous constituents to photolysis

David R. HOKANSON,Ke LI,R. Rhodes TRUSSELL

期刊论文