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Succession and biodiversity indices in eutrophication process of static landscaping water body in northern China

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Journal of Harbin Institute of Technology(New Series) 2008年第5期15卷 711-717页

作者：丛科明刘书宇马放张建祺任南琪 School of Municipal and Environmental Engineering Harbin Institute of Technology Shanghai Applied Radiation Institute Shanghai University dept.of civil and Environmental Engineering University of MarylandBaltimore County

Many biodiversity indices were used to indicate the biological contamination degree in studies of lake water or seawater. Some were studied on biodiversity comparison for different areas at the same time, or initial structure succession of some aerial lake water systems. The phytoplankton changed with the development of various dominant species. In this study, the dominant species at these stages were Chlorophyta in the beginning stage, Cyanophyta in the second stage, and Xanthophyta in the last stage. Seven of nine biodiversity indices (Margalef's, IE, Shannon-Wiener, Simpson's, McNaughton's, Species and Odds Measure of Diversity) showed their failure to represent the eutrophication trend, and the other two indices (Menhinick's and Monk) exhibited good efficiency to indicate the eutrophication trend for the static landscaping water body.

关键词： biodiversity indices eutrophication assessment static lake water

Analytical and Numerical Modelling of FRP Debonding from Concrete Substrate under Pure Shearing

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Journal of Wuhan University of Technology(Materials Science) 2012年第1期27卷 142-148页

作者： PAN Jinlong XU Zhun C K Y Leung LI Zongjin Key Laboratory of Concrete and Pre-stressed Concrete Structures of Ministry of Education Southeast UniversityNanjing 210096 dept.of civil and Environmental Engineering Hong Kong University of Science and TechnologyHongKongChina

External bonding of fiber reinforced polymer （FRP） composites on the concrete structures has been proved to be an effective and efficient way to strengthen concrete structures. For a FRP strengthened concrete beam, it is usually observed that the failure occurs in the concrete and a thin layer of concrete is attached on the surface of the debonded FRP plate. To study the debond behavior between concrete and FRP composites, an analytical model based on the three-parameter model is developed to study the debonding behavior for the FRP-to-concrete joint under pure shearing. Then, nonlinear FEM analysis is conducted to verify the PrOposed analytical model. The FEM results shows good agreement with the results from the model. Finally, with the analytical model, sensitivity analyses are performed to study the effect of the interracial parameters or the ~eometric parameters on the debondin~ behavior.

关键词： FRP composites debonding behavior analytical model nonlinear FEM analysis

Bin-objective shape optimization based on linear programming model of arch dam

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Journal of Harbin Institute of Technology(New Series) 2007年第3期14卷 436-439页

作者：金海林皋阳明盛 School of Architecture and civil Engineering Xiamen University School of civil Eng.and Archit. Dalian Univ.of Technol. dept.of Appl.Math. Dalian Univ.of Technol.

Bin-objective shape optimization of arch dam based on linear programming model is discussed to minimize both dam volume and maximal tensile *** importance of weight coefficient of the above two objectives is chosen according to the value of importance *** influence of weight coefficient to the optimization result is discussed in detail and the numerical example shows that both the model and method proposed is doable.

关键词： optimization arch dam linear programming bin-objective

Generation of Synthetic Ground Motion

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Journal of Geological Resource and Engineering 2018年第3期6卷 105-111页

作者： Hari Ram Parajuli Rajesh Kumar Shrestha dept.of civil Engineering Pulchowk CampusTribhuwan UniversityNepal dept.of civil Engineering Thapathali CampusTribhuwan UniversityNepal

The main target of the study is to generate artificial earthquake time histories which are compatible with real earthquakes.A simple frequency-domain method for generating time histories from the given response spectrum is presented in this *** average response spectra are generated using three attenuation relationships developed for the subduction zonesuitable for Barpak M7.8 earthquake records at TU,*** ground motions are simulated with consideration of source,site,and *** simulation work is started from noise generation work with windowing,Fast Fourier Transform(FFT)and spectra matching(target and generated)to obtain simulated time history using MATLAB programming *** ground motions can be utilized as input ground motions for the dynamic analysis and design of new structures as well as retrofitting of existing structures.

关键词： Artificial earthquake weighted average response spectrum attenuation relationship Barpak Fast Fourier Transform

Determining a representative element volume for DEM simulations of samples with non-circular particles

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Particuology 2022年第9期20卷 29-43页

作者： Peter Adesina Catherine O'Sullivan Tokio Morimoto Masahide Otsubo dept.of civil and Environmental Engineering Imperial College LondonSouth KensingtonLondon SW72AZUK Institute of Industrial Science The University of Tokyo4-6-1 Komaba Meguro-kuTokyo 153-8505Japan

Numerical studies on the number of particles or system size required to attain a representative element volume(REV)for discrete element method(DEM)simulations of granular materials have almost always considered samples with spherical or circular *** study considers how many particles are needed to attain a REV for 2D samples of 2-disc cluster particles where the particle aspect ratio(AR)was systematically *** and loose assemblies of particles were *** minimum REV was assessed both by considering the repeatability of static packing characteristics and the shearing behaviour in biaxial compression tests,and by investigating the effect of sample size on the measured characteris-tics and observed shearing *** repeatability of the data considered generally improved with increasing sample *** packing characteristics of the dense samples were more repeatable suggest-ing that the minimum REV reduces with increasing packing *** minimum REV was observed to be sensitive to the characteristic *** the overall responses of the samples during shear deformation were similar irrespective of the sample sizes,the smaller the sample size,the higher the fluctuations observed in the *** of the coefficient of variation of the fluctuations around the critical state stress ratio can provide insight as to whether a REV is *** particle AR influences the effect of sample size on shearing characteristics and thus the minimum number of particles required to attain a REV;this can be explained by the influence of AR on the number of contacts within the samples.

关键词： DEM Representative element volume Non-circular particles Particle shape Granular materials

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Journal of Green Building 2006年第4期1卷 141-151页

作者： A.Parker M.Aschheim D.Mar M.Hammer B.King dept.of civil Engineering Santa Clara UniversitySanta ClaraCA 95053 Tipping-Mar+Associates BerkeleyCA 94704 不详

Experimental studies on full-scale straw-bale walls have demonstrated the adequacy of straw-bale wall systems for resisting lateral loads from wind or seismic *** to the performance of the wall system is the anchorage of mesh reinforcement to the bottom plate and to the roof bearing assembly or top *** in this paper are the results of experiments examining mesh strength,anchorage strength,and failure mode for a variety of reinforcement meshes(steel,plastic,and hemp)and anchorage *** of the potential for new wood preservative pressure treatments to cause corrosion,stainless steel staples driven pneumatically into pressure-treated sill plates were tested in addition to electro-galvanized staples driven pneumatically into untreated sill plates and a heavier gauge staple driven manually into an untreated sill *** anchorage details are identified,considering not only the test results but also the many other factors that must be considered in developing reliable,economical,and constructible details.

关键词： straw bale mesh details mesh anchorage mesh strength staples

Interpretable modeling of metallurgical responses for an industrial coal column flotation circuit by XGBoost and SHAP-A “conscious-lab” development

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International Journal of Mining Science and Technology 2021年第6期31卷 1135-1144页

作者： S.Chehreh Chelgani H.Nasiri M.Alidokht Minerals and Metallurgical Engineering Dept.of CivilEnvironmental and Natural Resources EngineeringLuleåUniversity of TechnologySE-97187 LuleåSweden Department of Computer Engineering Amirkabir University of TechnologyTehranIran Tabas Parvardeh Coal Company(TPCCO) BirjandIran

Surprisingly,no investigation has been explored relationships between operating variables and metallurgical responses of coal column flotation(CF) circuits based on industrial databases for under operation *** a novel approach,this study implemented a conscious-lab "CL" for filling this *** this approach,for developing the CL dedicated to an industrial CF circuit,SHapley Additive explanations(SHAP) and extreme gradient boosting(XGBoost) were powerful unique machine learning systems for the first time *** explainable artificial intelligence models could effectively convert the dataset to a basis that improves human capabilities for better understanding,reasoning,and planning the *** could provide precise multivariable correlation assessments between the CF dataset by using the Tabas Parvadeh coal plant(Kerman,Iran),and showed the importance of solid percentage and washing water on the metallurgical responses of the coal CF *** could predict metallurgical responses(R-square> 0.88) based on operating variables that showed quite higher accuracy than typical modeling methods(Random Forest and support vector regression).

关键词： SHAP XGBoost Explainable AI Coal flotation Separation efficiency

Seismic risk assessment for developing countries: Pakistan as a case study

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Earthquake Engineering and Engineering Vibration 2018年第4期17卷 787-804页

作者： Shaukat A.Khan Kypros Pilakoutas Iman Hajirasouliha Reyes Garcia Maurizio Guadagnini dept. of civil Engineering Abasyn University dept. of civil and Structural Engineering The University of Sheffield

Modern Earthquake Risk Assessment（ERA） methods usually require seismo-tectonic information for Probabilistic Seismic Hazard Assessment（PSHA） that may not be readily available in developing countries. To bypass this drawback, this paper presents a practical event-based PSHA method that uses instrumental seismicity, available historical seismicity, as well as limited information on geology and tectonic setting. Historical seismicity is integrated with instrumental seismicity to determine the long-term hazard. The tectonic setting is included by assigning seismic source zones associated with known major faults. Monte Carlo simulations are used to generate earthquake catalogues with randomized key hazard parameters. A case study region in Pakistan is selected to demonstrate the effectiveness of the method. The results indicate that the proposed method produces seismic hazard maps consistent with previous studies, thus being suitable for generating such maps in regions where limited data are available. The PSHA procedure is developed as an integral part of an ERA framework named EQRAM. The framework is also used to determine seismic risk in terms of annual losses for the study region.

关键词： recycled concrete frame-shear wall concealed bracings shaking table test nonlinear time-history responseanalysis

Settling basin design in a constructed wetland using TSS removal efficiency and hydraulic retention time

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Journal of Environmental Sciences 2014年第9期26卷 1791-1796页

作者： Soyoung Lee Marla C.Maniquiz-Redillas Lee-Hyung Kim Water Environment Research dept. National Institute of Environmental ResearchHwangyeong-ro 42Seo-guIncheon 404-708Korea dept.of civil & Envi.Eng'g. Kongju National University275 BudaedongSeobukguCheonanChungnamdo 331-717Korea

Using total suspended solid （TSS） removal efficiency and hydraulic retention time （HRT） as design parameters a design guideline of a settling basin in a constructed wetland （CW） was suggested; as well as management of sediment and particle in the settling basin. The CW was desiEned to treat the piggery wastewater effluent from a wastewater treatment plant during dry days and stonnwater runoff from the surrounding paved area during wet days. The first settling basin （FSB） in the CVV was theoretically designed with a total storage volume （TSV） of 453 ms and HRT of 5.5 hr. The amount of sediment and particles settled at the FSB was high due to the sedimentation and interception of plants in the CVV. Dredging of sediments was performed when the retention rate at the FSB decreased to approximately 80%. Findings showed that the mean flow rate was 21.8 m3/hr less than the designed flow rate of 82.8 m3/hr indicating that the FSB was oversize and operated with longer HRT （20.7 hr） compared to the design HRT. An empirical model to estimate the length of the settling basin in the CW was developed as a function of HRT and desired TSS removal efficiency. Using the minimum tolerable TSS removal efficiency of 30%, the length of the FSB was estimated to be 31.2 m with 11.8 hr HRT.

关键词： Constructed wetlandHydraulic retention timeParticle size distributionSettling basin designTSS removal efficiency