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World Journal of Emergency Medicine 2023年第3期14卷 231-234页

作者： mehdi torabi Javad Darijani Moghaddameh Mirzaee Amin Honarmand Department of Emergency Medicine Clinical Research Development UnitShahid Bahonar HospitalKerman University of Medical SciencesKerman ***Iran Health Research Center Institute for Futures Studies in HealthKerman University of Medical SciencesKerman ***Iran

Due to the acute and terrible pain that patients with renal colic experience,the most essential therapeutic priority for these patients in the emergency department(ED)is to reduce pain.[1]Although numerous medications are utilized to reduce pain in patients with acute renal colic,no therapy has yet been developed to totally and quickly relieve pain.[2,3]Intravenous opioids and nonsteroidal anti-inflammatory drugs(NSAIDs)are commonly administered intravenously to control pain in these patients in the ED;however,the need for frequent monitoring for possible complications and relatively slow-acting features render these strategies undesirable.

关键词： pain acute drugs

Intensity measures for the seismic response evaluation of buried steel pipelines under near-field pulse-like ground motions

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Earthquake Engineering and Engineering Vibration 2019年第4期18卷 917-931页

作者： Alireza Kiani mehdi torabi S.Mohammad Mirhosseini Department of Civil Engineering Islamic Azad University Arak Branch Arak 12346 Iran Department of Civil Engineering Islamic Azad University Kangan Branch Kangan 12345 Iran Department of Civil Engineering Islamic Azad University Arak Branch Arak 34125 Iran

Ground-motion Intensity Measures (IMs) are used to quantify the strength of ground motions and evaluate the response of structures. IMs act as a link between seismic demand and seismic hazard analysis and therefore, have a key role in performance-based earthquake engineering. Many studies have been carried out on the determination of suitable IMs in terms of effi ciency, suffi ciency and scaling robustness. The majority of these investigations focused on ordinary structures such as buildings and bridges, and only a few were about buried pipelines. In the current study, the optimal IMs for predicting the seismic demand of continuous buried steel pipelines under near-fi eld pulse-like ground motion records is investigated. Incremental dynamic analysis is performed using twenty ground motion records. Using the results of the regression analysis, the optimality of 23 potential IMs are studied. It is concluded that specifi c energy density (SED) followed by VSI[ω1(PGD+RMSd )] are the optimal IMs based on effi ciency, suffi ciency and scaling robustness for seismic response evaluation of buried pipelines under near-fi eld ground motions.

关键词： continuous buried steel pipeline intensity measure scaling robustness pulse-like ground motion records performance-based earthquake engineering

An Experimental Investigation on the Stability of Foundation of Composite Vertical Breakwaters

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Journal of Marine Science and Application 2015年第2期14卷 175-182页

作者： Mohammad Amin torabi mehdi Shafieefar Department of Civil Engineering Tarbiat Modares University Tehran 14115-143 Iran

一系列 2D 模型测试被进行估计合成垂直防波提的基础稳定性。在这篇论文，从试验性的学习的结果与一个公式相连地被介绍估计基础的稳定性数字，它是为如此的结构的基础稳定性的评估的最重要的参数。有不同盔甲石头尺寸的合成防波提的稳... 详细信息

一系列 2D 模型测试被进行估计合成垂直防波提的基础稳定性。在这篇论文，从试验性的学习的结果与一个公式相连地被介绍估计基础的稳定性数字，它是为如此的结构的基础稳定性的评估的最重要的参数。有不同盔甲石头尺寸的合成防波提的稳定性上的波浪高度，波浪时期和城墙与外濠间之狭道宽度的影响被调查。45 测试被执行盖住这些参数的影响。根据现在的研究，城墙与外濠间之狭道宽度是有关盔甲基础的侵蚀的一个重要参数。作为城墙与外濠间之狭道宽度增加，城墙与外濠间之狭道侵蚀的数量减少。比较在现在的学习和 Kimura 等建议的估计的稳定性数字的结果之间被做。(1994 ) ，它是 Tanimoto 的扩展公式。结果证明以后的公式低估稳定性数字。然而，由使用一个改进因素大约 1.7 米到 Kimura 等。公式，结果与现在的试验性的结果相关……

关键词：地基稳定性防波堤实验复合垂直稳定性评价尺寸稳定性模型试验

Data-Based Filters for Non-Gaussian Dynamic Systems With Unknown Output Noise Covariance

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 866-877页

作者： Elham Javanfar mehdi Rahmani the Department of Electrical Engineering Imam Khomeini International UniversityQazvin ***Iran

This paper proposes linear and nonlinear filters for a non-Gaussian dynamic system with an unknown nominal covariance of the output noise.The challenge of designing a suitable filter in the presence of an unknown covariance matrix is addressed by focusing on the output data set of the system.Considering that data generated from a Gaussian distribution exhibit ellipsoidal scattering,we first propose the weighted sum of norms(SON)clustering method that prioritizes nearby points,reduces distant point influence,and lowers computational cost.Then,by introducing the weighted maximum likelihood,we propose a semi-definite program(SDP)to detect outliers and reduce their impacts on each cluster.Detecting these weights paves the way to obtain an appropriate covariance of the output noise.Next,two filtering approaches are presented:a cluster-based robust linear filter using the maximum a posterior(MAP)estimation and a clusterbased robust nonlinear filter assuming that output noise distribution stems from some Gaussian noise resources according to the ellipsoidal clusters.At last,simulation results demonstrate the effectiveness of our proposed filtering approaches.

关键词： Data-based filter maximum likelihood estimation unknown covariance weighted maximum likelihood estimation weighted sum-of-norms clustering

Reinforcement Learning-Empowered Graph Convolutional Network Framework for Data Integrity Attack Detection in Cyber-Physical Systems

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 797-806页

作者： Edeh Vincent mehdi Korki mehdi Seyedmahmoudian Alex Stojcevski Saad Mekhilef School of Science Computingand Engineering TechnologiesSwinburne University of TechnologyMelbourneAustralia

The massive integration of communication and information technology with the large-scale power grid has enhanced the efficiency, safety, and economical operation of cyber-physical systems. However, the open and diversified communication environment of the smart grid is exposed to cyber-attacks. Data integrity attacks that can bypass conventional security techniques have been considered critical threats to the operation of the grid. Current detection techniques cannot learn the dynamic and heterogeneous characteristics of the smart grid and are unable to deal with non-euclidean data types. To address the issue, we propose a novel Deep-Q-Network scheme empowered with a graph convolutional network (GCN) framework to detect data integrity attacks in cyber-physical systems. The simulation results show that the proposed framework is scalable and achieves higher detection accuracy, unlike other benchmark techniques.

关键词： Deep reinforcement learning graph convolutional network heterogeneous smart grid network

A novel mitigation measure for normal fault-induced deformations on pile-raft systems

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 15-33页

作者： Mohammadreza Jahanshahi Nowkandeh mehdi Ashtiani Faculty of Civil Engineering Babol Noshirvani University of TechnologyBabolIran

Evidence from recent earthquakes has shown destructive consequences of fault-induced permanent ground movement on structures.Such observations have increased the demand for improvements in the design of structures that are dramatically vulnerable to surface fault ruptures.In this study a novel connection between the raft and the piles is proposed to mitigate the hazards associated with a normal fault on pile-raft systems by means of 3D finite element(FE)modeling.Before embarking on the parametric study,the strain-softening constitutive law used for numerical modeling of the sand has been validated against centrifuge test results.The exact location of the fix-head and unconnected pile-raft systems relative to the outcropping fault rupture in the free-field is parametrically investigated,revealing different failure mechanisms.The performance of the proposed connection for protecting the pile-raft system against normal fault-induced deformations is assessed by comparing the geotechnical and structural responses of both types of foundation.The results indicate that the pocket connection can relatively reduce the cap rotation and horizontal and vertical displacements of the raft in most scenarios.The proposed connection decreases the bending moment response of the piles to their bending moment capacity,verging on a fault offset of 0.6 m at bedrock.

关键词： normal fault rupture failure mechanism pile-raft system pocket connection finite element modeling

Application of Radial Basis Function Learning Algorithm in Petroleum Engineering： Bottom-Hole Pressure Prediction

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材料科学与工程（中英文A版） 2011年第4X期1卷 586-591页

作者： mehdi Mohammadpoor Farshid torabi Petroleum Systems Engineering Faculty of Engineering and Applied Science University of Regina Regina Canada

On the occurrence of Neoplanorbulinella Matsumaru, 1976(Foraminifera) from the late Oligocene of Central Iran(Qom Formation):Palaeobiogeographic implications

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Journal of Palaeogeography 2024年第1期13卷 80-91页

作者： mehdi Sarfi Mohsen Yazdi-Moghadam School of Earth Sciences Damghan UniversityDamghan ***Iran National Iranian Oil Company Exploration Directorate Sheikh Bahaie SquareTehran ***Iran

The shallow marine carbonates of the upper Oligocene Qom Formation yielded several occurrences of the foraminiferan genus Neoplanorbulinella Matsumaru. Neoplanorbulinella saipanensis Matsumaru has so far been recorded from the late Eocene-early Miocene of Japan and late Oligocene of NE Italy whereas N. malatyaensis Gedik is only reported from the Oligocene from its type locality in the Malatya Basin, eastern Turkey. The new records reported here from the Qom Formation indicate that both species occur in the Dobaradar section, ca. 10 km south of the city of Qom in North-Central Iran. The palaeogeographic distribution of these two species therefore has to be extended as far as the palaeolongitude of current Central Iran.The accompanying larger benthic foraminifers, including Miogypsinoides complanatus(Schlumberger),M. formosensis Yabe and Hanzawa, Spiroclypeus margaritatus(Schlumberger), Operculina complanata(Defrance), and Risananeiza pustulosa Boukhary et al., indicate the upper Chattian SBZ 23 Zone. The coexistence of the N. saipanensis and N. malatyaensis points to suitable palaeobiogeographic conditions of Central Iran to host Western and Eastern Tethyan taxa.

关键词： Larger foraminifers Planorbulinids Biostratigraphy Qom Formation Central Iran

Evaluating innovation ecosystem resiliency using agent-based modeling and systems dynamics

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Journal of Safety Science and Resilience 2024年第2期5卷 204-221页

作者： Soheila Abdi mehdi Yazdani Esmaeil Najafi Department of Industrial Engineering Science and Research BranchIslamic Azad UniversityTehranIran Department of Industrial Engineering Qazvin BranchIslamic Azad UniversityQazvinIran

Evaluating the resilience of the innovation ecosystem to maintain its performance,in the sense of resistance to disruption and recovery after it,has recently received more attention.Several studies have been conducted to model different ecosystems and evaluate their resilience.However,modeling the innovation ecosystem from a holistic perspective and performing a quantitative assessment of its resilience have received less attention.This paper models the innovation ecosystem holistically and evaluates its resilience index using a quantitative approach through five main steps.In the first step,a case study related to the innovation ecosystem of Iran's Ministry of Energy,called the Power Innovation Ecosystem,is modeled by combining system dynamics and agent-based modeling.Upon validating the model in the second step,the disruption of the loss of experts is investigated in the third step,and all possible actions to recover each actor are analyzed.In the fourth step,the performance of the ecosystem is simulated before and after the disruption using the data gathered in the previous steps.Finally,resilience is calculated in two different ways in the fifth step.Several improvement solutions are also suggested when considering that the resilience index of the innovation ecosystem is at a medium level.This research may assist policymakers in observing the resilience level of the innovation ecosystem based on the proposed model.By applying strategic changes to this model,they can determine the effects of their policies and make the most appropriate decisions to increase the resilience of the innovation ecosystem.

关键词： Resilience index innovation ecosystem System dynamics Agent-based modeling

Coupling of RANS and BEM Solvers for Simulation of Propeller Behind the Hull in Full Appended Model

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China Ocean Engineering 2024年第3期38卷 424-438页

作者： Saeed NAJAFI mehdi POURMOSTAFA LIU Peng-fei Iranian National Institute for Oceanography and Atmospheric Science(INIOAS) Tehran 14155-4781Iran Department of Maritime Engineering Amir Kabir University of TechnologyTehran 15875-4413Iran Marine Offshore and Subsea TechnologySchool of EngineeringNewcastle UniversityNewcastle upon TyneNE17RUUK

To design a propeller for ship power plant,the interaction between ship hull and propeller must be taken into account.The main concern is to apply the wake effect of ship stern on the propeller performance.In this paper,a coupled BEM(Boundary Element Method)/RANS(Renolds-Averaged Navier−Stokes)solver is used to simulate propeller behind the hull in the self-propulsion test.The motivation of this work is to develop a practical tool to design marine propulsion system without suffering long computational time.An unsteady boundary element method which is also known as panel method is chosen to estimate the propeller forces.Propeller wakes are treated using a time marching wake alignment method.Also,a RANS code coupled with VoF equation is developed to consider the ship motions and wake field effects in the problem.A coupling algorithm is developed to interchange ship wake field to the potential flow solver and propeller thrust to the RANS code.Based on the difference between hull resistance and the propeller thrust,a PI controller is developed to compute the propeller RPM in every time step.Verification of the solver is carried out using the towing tank test report of a 50 m oceanography research vessel.Wake factor and trust deduction coefficient are estimated numerically.Also,the wake rollup pattern of the propeller in open water is compared with the propeller in real wake field.

关键词： RANS BEM coupled method ship propeller self-propulsion wake sheet pattern