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Surface settlement induced by horizontal directional drilling

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Underground Space 2023年第1期8卷 94-108页

作者： Asif Ahmed md Azijul Islam md Zahangir Alam Hashmi S.Quazi College of Engineering State University of New York Polytechnic Institute(SUNY Poly)UticaNY 13502USA Department of Civil Engineering The University of Texas at ArlingtonArlingtonTX 76019USA Department of Civil Engineering Bangladesh University of Engineering and Technology(BUET)Dhaka 1000Bangladesh Converse Consultants RedlandsCA 92373USA

Horizontal directional drilling(HDD)is a widely used trenchless method for underground utility *** associated ground settlement triggered by HDD depends on the size,types,and surface texture of pipe,diameter of borehole,and soil *** pre-sent study investigates the surface settlement due to the construction of a 1067 mm diameter HDD,which will replace an existing sewer siphon under the SR-60 highway in Chino,California using empirical,and numerical *** on the results obtained from the subsurface investigation,an empirical analysis was conducted *** by numerical modeling of the HDD using PLAXIS 2D soft-ware.A careful comparison between two different methods indicated closer values of surface settlement between the empirical method(7.3 mm)and the numerical modeling(4.6 mm).In addition,the shape of surface settlement and horizontal settlement curves for the empirical and numerical methods was found to be *** minor discrepancy between the two methods resulted as the numerical model can host several soil layers whereas the empirical equation can use only one type of ***,a parametric study was conducted to evaluate the effect of borehole cover depth,size,and soil parameters on surface *** was observed that soil strength param-eters yielded a greater effect on surface movement,whereas modulus of elasticity has a relatively smaller influence with zero contribution from Poisson’s ratio.

关键词： Horizontal directional drilling(HDD) Surface settlement Cover depth Soil arching Borehole

Sensitivity analysis of the DehumReq model to evaluate the impact of predominant factors on dehumidification requirement of greenhouses in cold regions

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Information Processing in Agriculture 2023年第2期10卷 216-228页

作者： md Sazan Rahman Huiqing Guo Department of Mechanical Engineering University of Saskatchewan57 Campus driveSaskatoonSK S7N 5A9Canada Department of Bioresource Engineering McGill UniversityMacdonald Stewart Building21111 Lakeshore RoadSainte-Anne-de-BellevueQC H9X 3V9Canada

In this study,the sensitivity of a novel dehumidification requirement model(DehumReq)is analyzed to evaluate the effect of the predominant factors on the dehumidification needs of the *** hourly dehumidification demand and sensitivity coefficient(SC)are estimated for three different seasons:warm(July),mild(May),and cold(November),by using the local sensitivity analysis *** on SC values,the solar radiation,air exchange,leaf area index(LAI),and indoor setpoints(temperature,relative humidity(RH),and water vapor partial pressure(WVPP))have significant impact on the dehumidifi-cation needs,and the impact varies from season to *** parameters have a higher SC in summer,whereas solar radiation and LAI have a higher SC in mild *** dehumidification load increases 4 times of its base value with increasing solar radiation by 200 W/m^(2),and the highest LAI(10)caused 5 times increment of the *** changing of WVPP from its base value(1.5 kPa)to maximum(2.9 kPa)reduces the load 70%in *** exchange was found to be the most crucial parameter because it is the main dehumidification approach that has a large range and is easily adjustable for any *** air exchange by ventilation or infiltration will reduce the dehumidification load to zero in May and November and minimizes it to only nighttime load in *** the other parameters,higher ambient air RH and indoor air speed will result in higher the dehumidification load;whereas higher inner surface condensation will result in lower dehumidifi-cation *** result of this study will assist in the selection of the most efficient moisture control strategies and techniques for greenhouse humidity control.

关键词： Greenhouse Dehumidification DehumReq model Sensitivity analysis Solar radiation Air exchange

Influences of Biochar and Biochar-Mineral Complex on Mycorrhizal Colonisation and Nutrition of Wheat and Sorghum

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Pedosphere 2015年第5期25卷 686-695页

作者： Paul BLACKWELL Stephen JOSEPH Paul MUNROE Hossain M.ANAWAR Paul STORER Robert J.GILKES Zakaria M.solaiman Department of Agriculture and Food Western Australia Geraldton Regional Office School of Materials Science and Engineering University of New South WalesSydney Discipline of Chemistry University of Newcastle University of Wollongong School of Earth and Environment and UWA Institute of Agriculture The University of Western Australia Australian Mineral Fertilisers Pty Ltd. Soil Biology and Molecular Ecology Group School of Earth and Environment and UWA Institute of AgricultureThe University of Western Australia

The high price of synthetic fertilisers and the price barrier for biochar as a soil amendment have encouraged the exploration of using biochar in fertiliser replacement formulations. Biochars coupled with fertilisers can be applied at lower application rates to achieve benefits in plant growth and nutrition, as well as soil biological fertility. It is necessary to evaluate the use of biochar as a fertiliser substitute. Therefore, this study investigated the comparative influences of biochars, including Acacia saligna （AS）, Simcoa jarrah （S J） and Wundowie jarrah （W J）, mineral fertiliser with microbes （MF ＋ M）, biochar-mineral complex （BMC） and their combination on mycorrhizal colonisation, growth and nutrition of wheat in a glasshouse experiment and sorghum in field conditions. BMC ＋ MF ＋ M treatment produced higher mycorrhizal colonisation than MF ＋ M alone, indicating that BMC had a significant role in increasing mycorrhizal colonisation. SJ （treated with acetic acid） and MF ＋ M treatments, as well as AS ＋ MF ＋ M application, showed similar effects on mycorrhizal colonisation, but lower colonisation than the BMC ＋ MF ＋ M treatment. Ovcrall~ the BMC ＋ MF ＋ M treatment supported the maximum shoot, root and total plant dry weight followed by AS ＋ MF ＋ M and WJ ＋ MF ＋ M. The MF ＋ M treatment had the maximum shoot N and K concentrations, while BMC ＋ MF ＋ M application had the maximum shoot P concentration. AS ＋ MF -4- M and WJ ＋ MF ＋ M treatments supported the maximum N uptake by wheat shoots, while BMC ＋ MF ＋ M supported the maximum P uptake. The results showed that biochars and BMCs could increase mycorrhizal colonisation, plant growth and nutrient uptake of wheat, particularly N, P, K, S and Zn. The field experiment confirmed that BMC application at a rate of 300 kg ha-1 could increase the yield of irrigated sorghum on a loam soil and provide better applied P use efficiency compared to a water-soluble fertiliser alone. These results indicated that biochar-based fer

关键词： carbon sequestration nutrient uptake P use efficiency soil biological fertility wheat production

Design of a Simple Integrated Coupler for SPP Excitation in a Dielectric Coated Ag Thin Film

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Chinese Physics Letters 2014年第6期31卷 94-97页

作者： Rakibul Hasan Sagor md. Ruhul Amin md. Ghulam Saber Department of Electrical and Electronic Engineering Islamic University of Technology Board Bazar Gazipur-1704 Bangladesh

A simple integrated coupler is proposed for the efficient excitation of surface plasmon polariton （SPP） mode in a thin metal film. The SPP mode is generated in a single Ag-dielectric interface by the incident field and coupled with an Ag thin film. The coupling efficiency at different wavelengths using two different dielectrics, gallium lanthanum sulfide （GLS） and aluminum gallium arsenide （AIGaAs） is calculated by analyzing the SPP propagation dynamics with the finite difference time domain method. A maximum coupling efficiency of 70~ is obtained at a wavelength of 46Ohm when GLS is used, whereas the corresponding value obtained for A1GaAs is 60~o at 56Onto. The proposed structure can be used to excite SPPs in a nano-thin film from an external bulky source and is easier to fabricate since a single interface metal-dielectric configuration is used to excite the metal-thin film.

关键词： Efficiency

A Comparative Study of Dispersion Characteristics Determination of a Trapezoidally Corrugated Slow Wave Structure Using Different Techniques

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Chinese Physics Letters 2016年第1期33卷 132-135页

作者： md.Ghulam Saber Rakibul Hasan Sagor md.Ruhul Amin Department of Electrical and Electronic Engineering Islamic University of Technology

The linear dispersion relation of a trapezoidally corrugated slow wave structure （TCSWS） is analyzed and presented. The size parameters of the TCSWS are chosen in such a way that they operate in the x-band frequency range. The dispersion relation is solved by utilizing the Rayleigh-Fourier method by expressing the radial function in terms of the Fourier series. A highly accurate synthetic technique is also applied to determine the complete dispersion characteristics from experimentally measured resonances （cold test）. Periodic structures resonate at specific frequencies when the terminals are shorted numerical calculation, synthetic technique and cold appropriately. The dispersion characteristics obtained from test are compared, and an excellent agreement is achieved.

关键词： of on A Comparative Study of Dispersion Characteristics Determination of a Trapezoidally Corrugated Slow Wave Structure Using Different Techniques in been is

Proton conductivity performance and its correlation with physiochemical properties of proton exchange membrane(PEM)

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Chinese Journal of Chemical Engineering 2024年第10期74卷 100-116页

作者： Mirza Nusrat Sweety md Abdus Salam Hydrogen Energy Laboratory Bangladesh Council of Scientific and Industrial Research(BCSIR)Chattogram 4220Bangladesh Institute of Mining Mineralogy and Metallurgy(IMMM)BCSIRJoypurhat 5900Bangladesh BCSIR Dhaka Laboratories Dhaka 1205Bangladesh

Graphene oxide(GO)filler containing diversified Nafion-based proton exchange membrane(PEM)is studied to know the unique physical and chemical properties and performances of ***-SPEEK 1%-GO 0.75%(NSG-0.75%)composite shows the highest proton conductivity of 0.327 S·cm^(-1) at 90℃ and 100%RH(relative humidity)among all the PEM *** descending order of significant proton conductivity is found as;Nafion-sPGO(1%)0.306 S·cm^(-1)>Nafion/ZIF-8@GO 0.280 S·cm^(-1)>Nafion/PGO(2%)0.277 S·cm^(-1)>Nafion/GO-sulfur(3%)0.232 S·cm^(-1)>Nafion/GO-poly-SPM-co-PEGMEMA(1%)0.229 S·cm^(-1)>Nafion/Ce-sPGO(1%)0.215 S·cm^(-1).The proton conductivity,water uptake capacity and ion exchange capacity,hydration number,thermal and oxidative stability,mechanical integrity(tensile strength),maximum power,and current density are found to be increased while activation energy and fuel crossover show a decrement as GO or modified GO is incorporated in the Nafion *** component analysis(PCA)predicted a significant correlation between the proton conductivity and the properties;the water uptake capacity,ion exchange capacity,hydration number,maximum power density,and maximum current density are 0.598%,0.688%,0.894%,0.980%,and 0.852%accordingly.A multiple linear model equation of proton conductivity is defined with the parameters of water uptake capacity,ion exchange capacity,hydration number,maximum power density,and maximum current density whereas the regression coefficient is 0.9923.

关键词： Fuel cells Membranes Nafion GO-filler Proton conductivity Principal component analysis

Artifact suppression and analysis of brain activities with electroencephalography signals

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Neural Regeneration Research 2013年第16期8卷 1500-1513页

作者： md. Rashed-Al-Mahfuz md. Rabiul Islam Keikichi Hirose md. Khademul Islam Molla Department of Computer Science and Engineering Pabna University of Science and Technology Department of Information and Communication Engineering The University of Tokyo Department of Computer Science and Engineering Rajshahi University

Brain-computer interface is a communication system that connects the brain with computer （or other devices） but is not dependent on the normal output of the brain （i.e., peripheral nerve and muscle）. Electro-oculogram is a dominant artifact which has a significant negative influence on further analysis of real electroencephalography data. This paper presented a data adaptive technique for artifact suppression and brain wave extraction from electroencephalography signals to detect regional brain activities. Empirical mode decomposition based adaptive thresholding approach was employed here to suppress the electro-oculogram artifact. Fractional Gaussian noise was used to determine the threshold level derived from the analysis data without any training. The purified electroencephalography signal was composed of the brain waves also called rhythmic components which represent the brain activities. The rhythmic components were extracted from each electroencephalography channel using adaptive wiener filter with the original scale. The regional brain activities were mapped on the basis of the spatial distribution of rhythmic components, and the results showed that different regions of the brain are activated in response to different stimuli. This research analyzed the activities of a single rhythmic component, alpha with respect to different motor imaginations. The experimental results showed that the proposed method is very efficient in artifact suppression and identifying individual motor imagery based on the activities of alpha component.

关键词： neural regeneration brain activity brain waves data adaptive filtering electroencephalography electro-oculogram artifact topographic mapping Wiener filtering neuroregeneration

Stature estimation from footprint measurements in Bangladeshi adults

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Forensic Sciences Research 2022年第2期7卷 124-131页

作者： md Asadujjaman md Harun Or Rashid md Sohel Rana md Mosharraf Hossain Department of Industrial&Production Engineering Rajshahi University of Engineering&TechnologyRajshahiBangladesh

The estimation of stature is very important in forensic investigation,as it provides useful data that can narrow the pool of potentially matching *** purpose of this study was to develop formulae for the estimation of stature from footprint measurements in Bangladeshi *** study included 118 randomly selected men and 130 randomly selected women,all aged 18–50 *** each participant,stature and six footprint measurements were taken by means of standard measurement *** measurements were found to be positively correlated with *** was estimated by using linear regression *** right T1 length in men(R:þ0.587,R^(2):0.345)and the right T2 length in women(R:þ0.506,R^(2):0.256)were the most reliable individual estimators of ***,when data were combined for both sexes,the right T2 length was identified as the most reliable estimator of stature,with higher values of R(þ0.792)and R^(2)(0.627).In conclusion,human stature can be successfully estimated by using footprint measurements;this finding can be applied in forensic research and investigation.

关键词： Forensic sciences forensic anthropology anthropometry footprint stature estimation forensic identification

Variability in total antioxidant capacity, antioxidant leaf pigments and foliage yield of vegetable amaranth

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Journal of Integrative Agriculture 2018年第5期17卷 1145-1153页

作者： Umakanta Sarker md Tofazzal Islam md Golam Rabbani Shinya Oba Department of Genetics and Plant Breeding Faculty of AgricultureBangabandhu Sheikh Mujibur Rahman Agricultural University Laboratory of Field Science Faculty of Applied Biological ScienceGifu University Department of Biotechnology Faculty of AgricultureBangabandhu Sheikh Mujibur Rahman Agricultural University Department of Horticulture Faculty of AgricultureBangladesh Agricultural University

Twenty vegetable amaranth genotypes were evaluated for total antioxidant capacity, antioxidant leaf pigments, vitamins, and selection of suitable genotypes for extraction of juice in a randomized complete block design（RCBD） with three replications. Vegetable amaranth was rich in chlorophyll, β-cyanins, β-xanthins, betalains, carotene, ascorbic acid and total antioxidant. The genotypes VA14, VA16, VA18, VA15, and VA20 could be selected as amaranth vegtable varieties with high yields and abundance antioxidant leaf pigments and vitamins to produce juice. The genotypes VA13 and VA19 had above-average foliage yield and high antioxidant profiles while the genotypes VA2, VA3, VA9, VA11, VA12, and VA17 had a high antioxidant profiles and below-average foliage yield. These genotypes could be used as a donor parent for integration of potential high antioxidant profiles genes into other genotypes. The correlation study revealed a strong positive association among all the antioxidant leaf pigments, total antioxidant capacity and foliage yield. Selection based on total antioxidant capacity, antioxidant leaf pigments could economically viable to improve the yield potential of vegetable amaranth genotypes. Total carotene and ascorbic acid exhibited insignificant genotypic correlation with all the traits except total antioxidant capacity. This indicates that selection for antioxidant vitamins might be possible without compromising yield loss.

关键词： ascorbic acid betalain carotene chlorophyll β-cyanins β-xanthins total antioxidant capacity foliage yield correlation