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On subsurface box-shaped lined tunnel under incident SH-wave propagation

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Frontiers of Structural and Civil Engineering 2021年第4期15卷 948-960页

作者： Mehdi PANJI saeed MOJTABAZADEH-HASANLOUEI Department of Civil Engineering Zanjan BranchIslamic Azad UniversityZanjan45156-58145Iran

In this paper,a half-plane time-domain boundary element method is applied to obtain the seismic ground response,including a subsurface box-shaped lined tunnel deployed in a linear homogenous elastic medium exposed to obliquely incident *** the boundary around the tunnel is required to be *** prepare an appropriate model by quadratic elements,a double-node procedure is used to receive dual boundary fields at corners as well as change the direction of the normal *** encoding the method in a previously confirmed computer program,a numerical study is carried out to sensitize some effective parameters,including frequency content and incident wave angle for obtaining a surface *** depth and impedance ratio of the lining are assumed to be *** responses are illustrated in the time and frequency domains as two/three-dimensional *** results showed that subsurface openings with sharp corners distorted the propagation path of the anti-plane waves to achieve the critical states on the ground *** present approach can be proposed to civil engineers for preparing simple underground box-shaped models with angular boundaries.

关键词： box-lined tunnel half-plane BEM surface response SH-wave time-domain

An Efficient Cyber Security and Intrusion Detection System Using CRSR with PXORP-ECC and LTH-CNN

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Computers, Materials & Continua 2023年第8期76卷 2061-2078页

作者： Nouf saeed Alotaibi Department of Computer Science College of Science and Humanities Al DawadmiShaqra UniversityShaqra11961Saudi Arabia

Intrusion Detection System(IDS)is a network security mechanism that analyses all users’and applications’traffic and detectsmalicious activities in *** existing IDSmethods suffer fromlower accuracy and lack the required level of security to prevent sophisticated *** problem can result in the system being vulnerable to attacks,which can lead to the loss of sensitive data and potential system ***,this paper proposes an Intrusion Detection System using Logistic Tanh-based Convolutional Neural Network Classification(LTH-CNN).Here,the Correlation Coefficient based Mayfly Optimization(CC-MA)algorithm is used to extract the input characteristics for the IDS from the input ***,the optimized features are utilized by the LTH-CNN,which returns the attacked and non-attacked *** that,the attacked data is stored in the log file and non-attacked data is mapped to the cyber security and data security *** prevent the system from cyber-attack,the Source and Destination IP address is converted into a complex binary format named 1’s Complement Reverse Shift Right(CRSR),where,in the data security phase the sensed data is converted into an encrypted format using Senders Public key Exclusive OR Receivers Public Key-Elliptic Curve Cryptography(PXORP-ECC)Algorithm to improve the data *** Security Laboratory-Knowledge Discovery inDatabases(NSLKDD)dataset and real-time sensor are used to train and evaluate the proposed *** suggested model is evaluated based on accuracy,sensitivity,and specificity,which outperformed the existing IDS methods,according to the results of the experiments.

关键词： Intrusion detection system logistic tanh-based convolutional neural network classification(LTH-CNN) correlation coefficient based mayfly optimization(CC-MA) cyber security

A novel approach for constructing a 3D model based on registering a mono image on a 3D model, applicable in Digital Earth

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International Journal of Digital Earth 2012年第2期5卷 91-105页

作者： Amir saeed Homainejad Independent Research Group on Geospatial TehranIran

The effect of Digital Earth on our life is *** and updating Geospatial data in Digital Earth is also *** paper presents the application of a new approach of image registration in Digital *** approach was developed based on registering a mono photograph on a master 3D *** result is a 3D vector model,which can be broadly applied in visualisation,mapping,geographic information system(GIS),planning,change detection,as well as Digital *** approach does not require parameters of correction for *** accuracy of the output depends on the accuracy of the master *** approach is very versatile and able to register any image on the digital elevation model,digital surface model and topographic 3D model.

关键词： Digital Earth image registration 3D model

Simulation of the Galactic Cosmic Ray Shadow of the Sun

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Chinese Physics Letters 2017年第12期34卷 79-83页

作者： Mohsin saeed 查敏曹臻 Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of Sciences University of Chinese Academy of Sciences State Key Laboratory of Space Weather Chinese Academy of Sciences

The cosmic-ray particles of TeV-regime, outside the solar system are blocked in their way to the Earth, a deficit of particles is observed corresponding to the location of the Sun known as the Sun shadow. The center of the Sun shadow is shifted from its nominal position due to the presence of magnetic fields in interplanetary space,and this shift is used indirectly as a probe to study the solar magnetic field that is difficult to measure otherwise.A detailed Monte Carlo simulation of galactic cosmic-ray propagation in the Earth-Sun system is carried out to disentangle the cumulative effects of solar, interplanetary and geomagnetic fields. The shadowing effects and the displacements results of the Sun shadow in different solar activities are reproduced and discussed.

关键词： Simulation of the Galactic Cosmic Ray Shadow of the Sun LHAASO IMF

Propulsion Performance of Spanwise Flexible Wing Using Unsteady Panel Method

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Journal of Ocean University of China 2020年第3期19卷 505-518页

作者： NAJAFI saeed LIU Pengfei Ocean Engineering and Technology Department Iranian National Institute for Oceanography(INIO)Tehran ***Iran Marine Offshore and Subsea TechnologySchool of EngineeringNewcastle UniversityNewcastle upon TyneNE17RUUK

In this paper, the propulsion performance of a spanwise flexible oscillating wing, which is broadly similar to the undulation of a fin fluke, is investigated. The geometry of the fluke underwent three prescribed harmonic oscillating motions simultaneously while surging with constant velocity. The effect of deflection phase angle, flexibility parameter, and wing tip deflection amplitude on thrust coefficient and swimming efficiency was studied. A low-order unsteady panel method coupled with a time stepping algorithm for free wake alignment is implemented in a computer program to estimate the propulsion efficiency of lifting bodies. A novel approach is introduced to evaluate the singular integrals of line vortices by using an adaptive mollifier function. This method is an efficient way to accelerate computational speed by reducing the order of problem from R^3 to body boundaries. Results present the significant effect of phase angle on the propulsion characteristics of oscillating fluke.

关键词： propulsion performance fin whale fluke flexible wing panel method wake alignment

Lead and zinc geochemical behavior based on geological characteristics in Parkam Porphyry Copper System, Kerman, Iran

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Journal of Central South University 2015年第11期22卷 4274-4290页

作者： Seyyed saeed Ghannadpour Ardeshir Hezarkhani Department of Mining & Metallurgical Engineering Amirkabir University of Technology(Tehran Polytechnic)

Parkam(Sarah) porphyry system is located on the metallogenic belt of Kerman, Iran. Due to existence of some copper-rich resources in this region, finding out the exact statistical characteristics such as distribution of data population, mean, variance and data population behavior of elements like Cu, Mo, Pb and Zn is necessary for interpreting their geological behavior. For this reason, precise calculation of statistical characteristics of Pb and Zn grade datasets was performed and results were interpreted geologically. The natures of Pb and Zn distributions were initially identified and their distributions were normalized through statistical treatment. Subsequently, the variograms were calculated for each exploration borehole and show that both Pb and Zn geochemical variates are spatially correlated. According to the similarity of the behavior of Pb and Zn in these calculations, it is decided to measure their exact behavior applying K-means clustering method. K-means clustering results show that the Zn grade varies linearly relative to that of Pb values and their behavior is similar. Based on the geochemical behavior similarity of Pb and Zn, throughout the pervasive secondary hydrothermal activity, they are remobilized in the similar manner, from the deep to the shallow levels of the mineralization zones. However, statistical analysis suggests that hydrothermal activity associated with secondary waters in Parkam is effective in remobilizing and enriching both Pb and Zn since they have similar geochemical characteristics. However, the process does not result in generation of economic concentrations.

关键词： Parkam porphyry copper Pb Zn statistical analysis

The plurality effect of topographical irregularities on site seismic response

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Earthquake Engineering and Engineering Vibration 2019年第3期18卷 521-534页

作者： saeed Ghaffarpour Jahromi Sama Karkhaneh Department of Civil Engineering Shahid Rajaee Teacher Training University

Topography can have signifi cant eff ects on seismic ground response during an earthquake because topographic irregularities cause considerable diff erences between the seismic waves emitted by the source and the waves reaching the ground surface. When a seismic motion happens in a topographically irregular area, seismic waves are trapped and refl ected between the topographic features. Therefore, the interaction between topographies can amplify seismic ground response. In order to reveal how interaction between topographies infl uences seismic response, several numerical fi nite element studies have been performed by using the ABAQUS program. The results show that topographic features a greater distance between the seismic source and the site would cause greater seismic motion amplifi cation and is perceptible for the hills far away from the source and the ridges. Also, site acceleration response is impacted by surrounding topography further than site velocity and displacement response.

关键词： Topography eff ects surrounding topography site seismic response ABAQUS Program and PLAXIS Program

Evaluation of sediment contamination in the Red Sea coastal area combining multiple pollution indices and multivariate statistical techniques

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International Journal of Sediment Research 2021年第2期36卷 243-254页

作者： Yousef saeed Saleh Biology Department Faculty of Science Taiz University

In the recent years, the Red Sea coast of Yemen has been severely affected by intensive anthropogenic activities. The current study constitutes a thorough inquiry to evaluate the extent of heavy metals pollution in Yemen’s Red Sea coast sediment and identifies the possible sources of pollution. The concentrations of five metals(copper(Cu), zinc(Zn), cadmium(Cd), lead(Pb), and nickel(Ni)) collected from nine sites along the Red Sea coast of Yemen were assessed using an atomic absorption spectrophotometer(ASS). Sediment quality indices, such as the sediment quality guidelines(SQGs), potential ecological risk(RI), contamination factor(CF), pollution load index(PLI), geoaccumulation index(Igeo), and modified degree of contamination(m Cd) were computed. In addition, multivariate statistical techniques(principal component analysis(PCA),hierarchical cluster analysis, and Pearson’s correlation analysis) were applied to identify the potential sources of metals. The mean concentrations of Cu, Zn, Cd, Pb, and Ni were 51.3, 61.9, 4.02, 9.9, and 33.4 mg/kg dry wt, respectively. The spatial distribution revealed that the metals concentrations were high at the middle zone and low southward of Hodeida city. According to the SQGs, the adverse biological effects of metals were occasionally associated with Cu and Cd, frequently associated with Ni, and not expected to occur with Zn and Pb. The RI indicated that the sediment of the studied sites pose low(RI Ni > Pb > Cd > Cu,whereas the PLI and m Cd indicated that Ras Isa(Site 5) and Urj village(Site 6) were the most polluted ***, cluster analysis, and correlation analysis found that Cd, Pb, and Ni mostly originated from anthropogenic

关键词： Red Sea Heavy metals Pollution Spatial distribution Sediment quality

Effect of hot rolling and annealing temperatures on the microstructure and mechanical properties of SP-700 alloy

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International Journal of Minerals,Metallurgy and Materials 2020年第3期27卷 374-383页

作者： Parnia Parvizian Maryam Morakabati saeed Sadeghpour Metallic Materials Research Center Malek Ashtar University of Technology

The effect of rolling temperature on both two-and single-phase regions and annealing in a temperature range of 700–950°C on the microstructure and mechanical properties of Ti-5 Al-4 V-2 Fe-1 Mo alloy was investigated. The results indicated that the best balance of strength and ductility is obtained by rolling in the two-phase region due to the globularization of the alpha phase and increase in its volume fraction. After rolling in the two-phase region, the ductility of the specimens annealed at 700 to 800°C increased because of the finer size and globularized alpha phase, while the reduction in strength was attributed to a decrease in the alpha phase volume fraction. However, at 950°C, the strength increased and ductility dropped by the formation of acicular alpha phase due to an increase in the phase boundary area. Annealing and aging after rolling in the beta-phase region increased the strength and decreased the ductility, which is attributed to the formation of a secondary alpha phase. A combination of favorable yield strength(1113 MPa) and elongation(13.3%) was obtained through rolling at 850°C followed by annealing at 750°C and aging at 570°C.

关键词： beta-rich two phase Ti alloy thermomechanical processing tensile properties microstructure