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Investigation on the effectiveness of pretreatment in stormwater management technologies

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Journal of environmental Sciences 2014年第9期26卷 1824-1830页

作者： Marla C.Maniquiz-Redillas Franz Kevin F.Geronimo Lee-Hyung Kim dept.of Civil and environmental engineering Kongju National UniversityCheonanChungnamdoSouth Korea

The effectiveness of presettling basins as component of stormwater best management practice （BMP） technologies was investigated. Storm event monitoring and sediment collection were conducted from May 2009 to November 2012 on the presettling basins of the three BMP technologies designed to capture and treat stormwater runoff from highly impervious roads and parking lots. Data on captured runoff and sediment, total suspended solids （TSS） loadings, rainfall and runoff rate, sediment accumulation rate, as well as particle distribution and pollutant concentrations of sediment were gathered and analyzed along with the physical design characteristics of the presettling basins such as surface area and storage volume. Regression models were generated to determine significant relationships between design parameters. Results revealed that the storage volume ratio （ratio of storage volume of presettling basin to BMP） was an important parameter in designing the presettling basin of the BMP. For practicality, optimizing the design of the presetfling basin means that the storage volume ratio should be determined based on the desired captured amount of runoff and sediment from runoff to limit the frequency of maintenance caused by the accumulation of sediment. It was recommended that pretreatment of runoff should be employed when the site in which the BMP is to be sited has high TSS loading and runoff rate, and is subjected to high intensity rainfall.

关键词： Best management practicePresettling basinPretreatmentSedimentStormwater runoff

Fluctuations and time scales for bed-load sediment motion over a smooth bed

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International Journal of Sediment Research 2015年第4期30卷 321-327页

作者： Francesco Ballio Alessio Radice Politecnico di Milano Dept.of Civil and Environmental Engineering

Results are presented for experiments of bed-load sediment transport over a plane,smooth *** smooth-bed configuration,though not adequate for mimicking natural streams,enables the effects of bed roughness to be filtered out,thus,highlighting the role of flow turbulence for particle *** were individually tracked along their paths,measuring position and velocity of the individual grains.A number of analyses were then applied to the data:probability density function,auto-correlation,and spectra of the grain *** Lagrangian time scales of particle motion were obtained and compared to available data for the turbulent flow field to determine a phenomenological interpretation of the process.

关键词： Bed load Smooth bed Sediment motion Particle velocity Fluctuations

Exploring relationships of gross calorific value and valuable elements with conventional coal properties for North Korean coals

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International Journal of Mining Science and Technology 2019年第6期29卷 867-871页

作者： Saeed Chehreh Chelgani Minerals and Metallurgical engineering Dept.of Civil Environmental and Natural Resources Engineering Lule? University of Technology

Coal in North Korean(NKC)is one of the most important products;however,based on various strategic policies its detail properties remain opaque even for general *** there are some signs for opening of the North Korea economy,this investigation as a modest effort is going to explore principle relationships among some essential parameters of NKCs such as gross calorific value(GCV),valuable elements and conventional properties by different statistical *** indicated that ultimate parameters(carbon,nitrogen,and hydrogen)are the best GCV predictors for NKCs in comparison with proximate parameters(ash,moisture and volatile matter).Multivariable regression demonstrated that predicted GCV based on ultimate properties has a quite accuracy when correlation of determination was *** statistics processes showed that on average,the contents of valuable elements such as Ga and V for NKCs are higher than the world coal ranges and they can be considered as byproducts of combustion of *** correlations indicated that Y may have a mixed organic-inorganic affinity while Ga and V mainly occur in the inorganic part(mineral matter)of *** inter-correlations between Ga-V and Al showed that aluminosilicates can be considered as their main bring minerals.

关键词： Yttrium Gallium Vanadium Calorific value Energy By product

Reliability-Based Optimal Design for Very Large Floating Structure

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海洋工程：英文版 2003年第1期17卷 11-20页

作者：张淑华 FUJIKUBO Masahiko Div.of Structural System engineering Dept.of Social and Environmental EngineeringGraduate School of Engineering

Costs and losses induced by possible future extreme environmental conditions and difficulties in repairing post yielding damage strongly suggest the need for proper consideration in design rather than just life loss prevention. This can be addressed through the development of design methodology that balances the initial cost of the very large floating structure (VLFS) against the expected potential losses resulting from future extreme wave induced structural damage. Here, the development of a methodology for determining optimal, cost effective design will be presented and applied to a VLFS located in the Tokyo bay. Optimal design criteria are determined based on the total expected life cycle cost and acceptable damage probability and curvature of the structure, and a set of sizes of the structure are obtained. The methodology and applications require expressions of the initial cost and the expected life cycle damage cost as functions of the optimal design variables. This study includes the methodology, total life cycle cost function, structural damage modeling, and reliability analysis.

关键词： very large floating structure reliability optimal design initial cost expected life cycle damage cost

Characteristics of MSWI fly ash during vitrification

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Journal of Harbin Institute of Technology(New Series) 2009年第1期16卷 107-110页

作者：田书磊王琪汪群慧马鸿志 dept.of environmental Science and Technology Harbin Institute of Technology dept.of environmental Science and engineering Tsinghua University Chinese Research Academy of environmental Science dept.of environmental Science and Technology Harbin Institute of Technology

The vitrification characteristics of municipal solid waste incinerator (MSWI) fly ash were investigated. Effects of temperature on the binding efficiency of heavy metals, the change of chemical compositions and the weight loss of fly ash in the range of 800-1350 ℃ were studied. Toxicity Characteristic Leaching Procedure (TCLP) of the United States was used to analyze the leaching characteristics of heavy metals in fly ash and molten slag. Results indicate that chemical compositions, the weight loss of fly ash and the binding efficiency of heavy metals in fly ash have a tremendous change in the range of 1150-1260 ℃. The percentage of CaO, SiO2 and Al2O3 increases with the increasing temperature, whereas it is contrary for SO3, K2O, Na2O and Cl; especially when the temperature is 1260 ℃, the percentage of these four elements decreases sharply from 43.72% to 0.71%. The weight loss occurs obviously in the range of 1150-1260 ℃. Heavy metals of Pb and Cd are almost vaporized above 1000 ℃. Cr is not volatile and its binding efficiency can reach 100% below 1000 ℃. Results of TCLP indicate that the heavy metal content of molten slag is beyond stipulated limit values.

关键词： heavy metal SWI fly ash caching concentration

Output only modal identification and structural damage detection using time frequency & wavelet techniques

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Earthquake engineering and engineering Vibration 2009年第4期8卷 583-605页

作者： S.Nagarajaiah B.Basu dept.of Civil & environmental Eng.and dept.of Mechanical Eng.& Material Sc. Rice University dept.of Civil Structural& Environmental Eng.Trinity College Dublin

The primary objective of this paper is to develop output only modal identification and structural damage detection. Identification of multi-degree of freedom （MDOF） linear time invariant （LTI） and linear time variant （LTV--due to damage） systems based on Time-frequency （TF） techniques--such as short-time Fourier transform （STFT）, empirical mode decomposition （EMD）, and wavelets--is proposed. STFT, EMD, and wavelet methods developed to date are reviewed in detail. In addition a Hilbert transform （HT） approach to determine frequency and damping is also presented. In this paper, STFT, EMD, HT and wavelet techniques are developed for decomposition of free vibration response of MDOF systems into their modal components. Once the modal components are obtained, each one is processed using Hilbert transform to obtain the modal frequency and damping ratios. In addition, the ratio of modal components at different degrees of freedom facilitate determination of mode shape. In cases with output only modal identification using ambient/random response, the random decrement technique is used to obtain free vibration response. The advantage of TF techniques is that they arc signal based; hence, can be used for output only modal identification. A three degree of freedom 1：10 scale model test structure is used to validate the proposed output only modal identification techniques based on STFT, EMD, HT, wavelets. Both measured free vibration and forced vibration （white noise） response are considered. The secondary objective of this paper is to show the relative ease with which the TF techniques can be used for modal identification and their potential for real world applications where output only identification is essential. Recorded ambient vibration data processed using techniques such as the random decrement technique can be used to obtain the free vibration response, so that further processing using TF based modal identification can be performed.

关键词： Time-frequency methods short time Fourier transform Hilbert transform wavelets modal identification:output only structural health monitoring damage detection

Analytical prediction and field validation of transient temperature field in asphalt pavements

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Journal of Central South University 2015年第12期22卷 4872-4881页

作者：陈嘉祺李亮汪浩 School of Civil engineering Central South University dept.of Civil and environmental engineering RutgersThe State University of New Jersey

This work presented the development and validation of an analytical method to predict the transient temperature field in the asphalt *** governing equation for heat transfer was based on heat conduction radiation and *** innovative time-dependent function was proposed to predict the pavement surface temperature with solar radiation and air temperature using dimensional analysis in order to simplify the complex heat exchange on the pavement *** parameters for the time-dependent pavement surface temperature function were obtained through the regression analysis of field measurement *** that the initial pavement temperature distribution was linear and the influence of the base course materials on the temperature of the upper asphalt layers was negligible,a close-form analytical solution of the temperature in asphalt layers was derived using Green's ***,two numerical examples were presented to validate the model solutions with field temperature *** results show that the solution accuracy is in agreement with field data and the relative errors at a shallower depth are greater than those at a deeper *** the model is not sensitive to dramatic changes in climatic factors near the pavement surface,it is applicable for predicting pavement temperature field in cloudless days.

关键词： asphalt pavement transient temperature field heat transfer dimensional analysis regression analysis Green’s function

Experimental Study of Improved HAWT Performance in Simulated Natural Wind by an Active Controlled Multi-Fan Wind Tunnel

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Journal of Thermal Science 2017年第2期26卷 113-118页

作者： Kazuhiko Toshimitsu Takahiko Narihara Hironori Kikugawa Arata Akiyoshi Yuuya Kawazu dept.of Information and Systems engineering Faculty of Information EngineeringFukuoka Institute of Technology3-30-1 Wajiro-higashiHigashi-kuFukuoka 811-0295Japan dept.of Energy and environmental engineering Interdisciplinary Graduate School of Engineering SciencesKyushu University dept.of Mechanical engineering Oita National College of Technology IHI Corporation Mechanical-environmental System engineering Major Oita National College of Technology

The effects of turbulent intensity and vortex scale of simulated natural wind on performance of a horizontal axis wind turbine(HAWT) are mainly investigated in this paper. In particular, the unsteadiness and turbulence of wind in Japan are stronger than ones in Europe and North America in general. Hence, Japanese engineers should take account of the velocity unsteadiness of natural wind at installed open-air location to design a higher performance wind turbine. Using the originally designed five wind turbines on the basis of NACA and MEL blades, the dependencies of the wind frequency and vortex scale of the simulated natural wind are presented. As the results, the power coefficient of the newly designed MEL3-type rotor in the simulated natural wind is 130% larger than one in steady wind.

关键词： Wind Turbine Wind Energy Natural Wind Unsteady Flow Rotor Design Turbulence

Synthesis and characterization on semi-aromatic polyamide containing benzoxazole unit

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Journal of Harbin Institute of Technology(New Series) 2011年第3期18卷 95-100页

作者：胡君贺金梅谷红波邱建辉黄玉东孙德智 School of Chemical engineering and Technology Harbin Institute of Technology dept.of Machine Intelligence and Systems engineering Akita Prefectural University School of municipal and environmental engineering Harbin Institute of Technology

In order to obtain a novel polyamide having excellent heat-resistant properties which could be anticipated as a thermal modifier for aliphatic polyamide,a series of new semi-aromatic polyamides (BO6,BO8,BO10) containing benzoxazole unit were synthesized based on 5-amino-2-(p-aminophenyl) benzoxazole (ABO) and aliphatic acids (adipic,suberic and sebacic acid) by means of Yamazaki phosphorylation *** effect of reaction temperature on the inherent viscosity of the polymers was studied,and the structures of products were characterized by FTIR,1 H-NMR,and the heat resistance of the polymers was studied by DSC and *** results showed that the reaction temperature gives the polymers the highest viscosity at around 90 ℃,130 ℃ and 130 ℃ for BO6,BO8 and BO10,*** heat resistance of the new semi-aromatic polyamides is much higher than that of the common aliphatic *** addition,the products show good solvent resistance and crystallization properties.

关键词： semi-aromatic polyamides benzoxazole synthesis thermal behavior