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A methodology for damage evaluation of underground tunnels subjected to static loading using numerical modeling

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 1993-2005页

作者： shahriyar Heidarzadeh ali saeidi Rock Mechanics Engineer AtkinsRéalisMontrealQuebecCanada department of Applied sciences Universitédu QuébecàChicoutimiChicoutimiQuebecCanada

We have proposed a methodology to assess the robustness of underground tunnels against potential *** involves developing vulnerability functions for various qualities of rock mass and static loading *** account for these variations,we utilized a Monte Carlo simulation(MCs)technique coupled with the finite difference code FLAC^(3d),to conduct two thousand seven hundred numerical simulations of a horseshoe tunnel located within a rock mass with different geological strength index system(GsIs)and subjected to different states of static *** quantify the severity of damage within the rock mass,we selected one stress-based(brittle shear ratio(BsR))and one strain-based failure criterion(plastic damage index(PdI)).Based on these criteria,we then developed fragility ***,we used mathematical approximation techniques to produce vulnerability functions that relate the probabilities of various damage states to loading intensities for different quality classes of blocky rock *** results indicated that the fragility curves we obtained could accurately depict the evolution of the inner and outer shell damage around the ***,we have provided engineers with a tool that can predict levels of damages associated with different failure mechanisms based on variations in rock mass quality and in situ stress *** method is a numerically developed,multi-variate approach that can aid engineers in making informed decisions about the robustness of underground tunnels.

关键词： Fragility curves Underground tunnels Vulnerability functions Brittle damage FLAC3d Numerical modeling

Using neural network modeling to improve the detection accuracy of land subsidence due to groundwater withdrawal

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Journal of Mountain science 2024年第7期21卷 2320-2333页

作者： ali M.RAJABI ali EdALAT Yasaman ABOLGHAsEMI Mahdi KHOdAPARAsT department of Engineering Geology University of TehranTehran ***Iran department of Civil Engineering University of QomQom ***Iran

despite the high efficiency of remote sensing methods for rapid and large-scale detection of subsidence phenomena,this technique has limitations such as atmospheric impact and temporal and spatial decorrelation that affect the accuracy of the *** paper proposes a method based on an artificial neural network to improve the results of monitoring land subsidence due to groundwater overexploitation by radar interferometry in the aliabad plain(Central Iran).In this regard,vertical ground deformations were monitored over 18 months using the sentinel-1A sAR *** model the land subsidence by a multilayer perceptron(MLP)artificial neural network,four parameters,including groundwater level,alluvial thickness,elastic modulus,and transmissivity have been *** model's generalizability was assessed using data derived for 144 *** to the results,the neural network estimates the land subsidence at each ground point with an accuracy of 6.8 mm.A comparison between the predicted and actual values indicated a significant *** MLP model can be used to improve the results of subsidence detection in the study area or other areas with similar characteristics.

关键词： dInsAR Land subsidence Groundwater withdrawal aliabad plain Artificial neural network

Integrated photonic fractional convolution accelerator

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Photonics Research 2024年第8期12卷 1828-1839页

作者： KEVIN ZELAYA MOHAMMEd-ali MIRI department of Physics Queens College of the City University of New YorkQueensNew York 11367USA Physics Program The Graduate Center of the City University of New YorkNew YorkNew York 10016USA

An integrated photonic circuit architecture to perform a modified-convolution operation based on the discrete fractional Fourier transform(dFrFT) is introduced. This is accomplished by utilizing two nonuniformly coupled waveguide lattices with equally spaced eigenmode spectra, the lengths of which are chosen so that the dFrFT and its inverse operations are achieved. A programmable modulator array is interlaced so that the required fractional convolution operation is performed. Numerical simulations demonstrate that the proposed architecture can effectively perform smoothing and edge detection tasks even for noisy input signals, which is further verified by electromagnetic wave simulations. Notably, mild lattice defects do not jeopardize the architecture performance, showing its resilience to manufacturing errors.

关键词： fractional convolution utilizing

Performance of Text-Independent Automatic speaker Recognition on a Multicore system

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Tsinghua science and Technology 2024年第2期29卷 447-456页

作者： Rand Kouatly Talha ali Khan Faculty of Tech and software Engineering University of Europe for Applied SciencesPotsdam 14469Germany

This paper studies a high-speed text-independent Automatic speaker Recognition(AsR)algorithm based on a multicore system's Gaussian Mixture Model(GMM).The high speech is achieved using parallel implementation of the feature's extraction and aggregation methods during training and testing *** memory parallel programming techniques using both OpenMP and PThreads libraries are developed to accelerate the code and improve the performance of the AsR *** experimental results show speed-up improvements of around 3.2 on a personal laptop with Intel i5-6300HQ(2.3 GHz,four cores without hyper-threading,and 8 GB of RAM).In addition,a remarkable 100%speaker recognition accuracy is achieved.

关键词： Automatic speaker Recognition(AsR) Gaussian Mixture Model(GMM) shared memory parallel programming PThreads OpenMP

CFd simulation and optimization of an industrial cement gas-solid air classifier

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Particuology 2024年第6期89卷 172-184页

作者： Mohamadreza Esmaeilpour ali Mohebbi Vahab Ghalandari department of Chemical Engineering Faculty of EngineeringShahid Bahonar University of KermanKermanIran Kerman Momtazan Cement Company KermanIran

An air classifier is one of the main and effective devices in cement *** this study,a three-dimensional,steady and two-phase(solid-gas)computational fluid dynamics(CFd)simulation was performed to optimize the performance of this device in the Kerman Momtazan cement plant,*** the validation of CFd results,the air flow field and air path lines between fixed blades were checked carefully and the non-uniformity in velocity distribution and the formation of vortex flows between the blades close to particle inlets were *** study tried to improve the device efficiency by changing the method of entering particles into the device,resulting in a reduction in air classifier electrical energy consumption(from 41 to 35(kW h)/t)and an increase in production rate(from 203 to 214 t/h).Additionally,the study investigated the effects of other modifiable operating conditions like rotary cage rotation speed,pressure difference,and inlet air temperature on the particle size distribution and classifier *** results showed that increasing the cage rotation speed decreased the product rate and the product particles mean diameter while increasing pressure difference or increasing temperature increased the product rate and the product particles mean *** was concluded that these modifiable operating conditions can significantly affect the performance of the air classifier in the cement industry.

关键词： Cement air classifier Computational fluid dynamics Gas-solid two-phase flow Optimization Eulerian-Lagrangian method Efficiency

sustainable pathways to ammonia:a comprehensive review of green production approaches

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Clean Energy 2024年第2期8卷 60-72页

作者： Hafiz sharjeel Ahmed Zaid Yahya Waqar ali khan ali Faraz University of Engineering and Technology(UET) LahorePakistan Chemical Engineering department NFC Institute of Engineering and Fertilizer ResearchFaislabadPakistan Chemical Engineering department Punjab UniversityLahorePakistan

Ammonia production is vital in global industries but faces increasing environmental concerns,necessitating a shift towards sustainable *** review comprehensively explores diverse hydrogen production approaches and their potential impact on sustainable ammonia *** primary focus is investigating hydrogen production methods that enhance both efficiency and sustainability in ammonia synthesis,which is crucial for reducing its environmental ***,the review highlights the pivotal role of catalysts in improving Faradaic efficiency in ammonia synthesis,emphasizing their significance in overall process *** study identifies innovative technologies that have the potential to revolutionize ammonia production while aligning with global sustainability *** a thorough examination of hydrogen production methods and catalytic advances,this review provides valuable insight into greener and more efficient ammonia production *** conclusion,it emphasizes the importance of exploring hydrogen production methods and leveraging catalysts to improve ammonia production sustainability and *** addresses a critical research gap and paves the way for an environmentally responsible and globally aligned ammonia production industry.

关键词： ammonia production green alternatives sustainability catalyst

Chemical-assisted MMP reduction on methane-oil systems:Implications for natural gas injection to enhanced oil recovery

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Petroleum 2024年第1期10卷 101-108页

作者： Mohamed Almobarak Matthew B.Myers Colin d.Wood Yongbing Liu ali saeedi Quan Xie discipline of Petroleum Engineering WA School of Mines:MineralsEnergy and Chemical EngineeringCurtin UniversityWestern AustraliaAustralia Commonwealth scientific and Industrial Research Organization Kensington6151Australia Curtin University Oil and Gas Innovation Centre Management Kensington6151Australia state Key Laboratory of Oil and Gas Reservoir Geology and Exploitation No.8 Xindu AvenueXindu DistrictChengdu 610500PR China

***,the main challenge in this process is the high minimum miscibility pressure(MMP)between natural gas and crude oil,which limits its application and recovery factor,especially in hightemperature ***,we present a novel investigation to quantify the effect of chemicalassisted MMP reduction on the oil recovery ***,we measured the interfacial tension(IFT)of the methane-oil system in the presence of chemical or CO_(2) to calculate the MMP reduction at a constant temperature(373K)using the vanishing interfacial tension(VIT)***,we performed three coreflooding experiments to quantify the effect of MMP reduction on the oil recovery factor under different injection *** interfacial tension measurements show that adding a small fraction(1.5 wt%)of the tested surfactant(sOLOTERRA ME-6)achieved 9%of MMP reduction,while adding 20 wt%of CO_(2) to the methane yields 13%of MMP ***,the coreflooding results highlight the significance of achieving miscibility during gas injection,as the ultimate recovery factor increased from 65.5%under immiscible conditions to 77.2%using chemical-assisted methane,and to 79%using gas mixture after achieving near miscible *** results demonstrate the promising potential of the MMP reduction to signifi-cantly increase the oil recovery factor during gas ***,these results will likely expand the application envelop of the miscible gas injection,in addition to the environmental benefits of utilizing the produced gas by re-injection/recycling instead of flaring which contributes to reducing the greenhouse gas emissions.

关键词： Gas injection Enhanced oil recovery Miscibility Coreflooding

Benchmarking YOLOv5 models for improved human detection in search and rescue missions

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Journal of Electronic science and Technology 2024年第1期22卷 70-80页

作者： Namat Bachir Qurban ali Memon Electrical Engineering department College of EngineeringUnited Arab Emirates UniversityAl Ain15551United Arab Emirates

drone or unmanned aerial vehicle(UAV)technology has undergone significant *** technology allows UAV to carry out a wide range of tasks with an increasing level of sophistication,since drones can cover a large area with ***,the increasing number of computer vision applications utilizing deep learning provides a unique insight into such *** primary target in UAV-based detection applications is humans,yet aerial recordings are not included in the massive datasets used to train object detectors,which makes it necessary to gather the model data from such *** only look once(YOLO)version 4,RetinaNet,faster region-based convolutional neural network(R-CNN),and cascade R-CNN are several well-known detectors that have been studied in the past using a variety of datasets to replicate rescue ***,we used the search and rescue(sAR)dataset to train the you only look once version 5(YOLOv5)algorithm to validate its speed,accuracy,and low false detection *** comparison to YOLOv4 and R-CNN,the highest mean average accuracy of 96.9%is obtained by *** comparison,experimental findings utilizing the sAR and the human rescue imaging database on land(HERIdAL)datasets are *** results show that the YOLOv5-based approach is the most successful human detection model for sAR missions.

关键词： Unmanned aerial vehicle(UAV) search and rescue(sAR) You look only once(YOLO)model You only look once version 5 (YOLOv5)

Effect of Rosmarinus officinalis and Origanum majorana extracts on stability of sunflower oil during storage and repeated heating

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Oil Crop science 2024年第1期9卷 29-37页

作者： ali sahunie department of Analytical and Food Chemistry Tishreen UniversityLattakiaSyria

Both rosemary(Rosmarinus officinalis)and marjoram(Origanum majorana)are abundant in phenolic compounds,exhibiting exceptional antioxidant *** study aims to assess the impact of rosemary and marjoram extracts on the stability of sunflower oil during storage and repeated *** oil supplemented with herbal extracts or butylated hydroxytoluene(BHA)at a concentration of 200 ppm was stored for six months under light and dark conditions at room *** value(PV),p-anisidine value(An-V),and total oxidation(TOTOX)value were measured to monitor lipid oxidation progression.A significant difference(Ps observed between light and dark storage for all studied samples regarding oxidation *** ethanolic extract of rosemary exhibited higher antioxidant activity compared to BHA and other ***,sunflower oil supplemented with the ethanolic extract of rosemary underwent weekly treatment at 100℃for 30 min over four consecutive *** all oxidation indicators increased during repeated heating,the addition of rosemary and marjoram extracts as well as BHA significantly reduced these *** findings demonstrate that both rosemary extracts and marjoram extracts can serve as natural antioxidants in edible oils.

关键词： Phenolic compounds BHA Marjoram extract Rosemary extract sunflower oil