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Modeling of fluid-induced vibrations and identification of hydrodynamic forces on flow control valves

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Journal of Central South University 2015年第7期22卷 2596-2603页

作者： Samad Mehrzad Ilgar Javanshir Ahmad Rahbar Ranji seyyed hadi taheri Department of Maritime Engineering Science and Research Branch Islamic Azad University Young Researchers and Elite Club Tabriz Branch Islamic Azad University Department of Maritime Engineering Amirkabir University

Dynamics and vibration of control valves under flow-induced vibration are analyzed. Hydrodynamic load characteristics and structural response under flow-induced vibration are mainly influenced by inertia, damping, elastic, geometric characteristics and hydraulic parameters. The purpose of this work is to investigate the dynamic behavior of control valves in the response to self-excited fluid flow. An analytical and numerical method is developed to simulate the dynamic and vibrational behavior of sliding dam valves, in response to flow excitation. In order to demonstrate the effectiveness of proposed model, the simulation results are validated with experimental ones. Finally, to achieve the optimal valve geometry, numerical results for various shapes of valves are compared. Rounded valve with the least amount of flow turbulence obtains lower fluctuations and vibration amplitude compared with the flat and steep valves. Simulation results demonstrate that with the optimal design requirements of valves, vibration amplitude can be reduced by an average to 30%.

关键词： flow-induced force hydrodynamic force finite element method(FEM) valve design fluid-structure interaction vibration

Faunal data and envenomation emergency first aid of cone snails (Conus spp.) in Qeshm Island, the Persian Gulf

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Asian Pacific Journal of Tropical Medicine 2017年第12期10卷 1167-1171页

作者： Mehdi Khoobdel hadi Dehghani Ali Mehrabi Tavana Mohammad Ghasemi seyyed Mohammad Dakhteh Majid Askari Hesni Mohsen Rezaie-Atagholipour Health Research Center Baqiyatallah University of Medical SciencesTehranIran Department of Marine Biology Faculty of ScienceUniversity of HormozganBandar AbbasIran Health Management Research Center Baqiyatallah University of Medical SciencesTehranIran Environmental Management Office Qeshm Free Area OrganizationQeshm IslandIran Department of Biology Faculty of ScienceShahid Bahonar University of KermanKermanIran

Objective: To investigate the fauna of a highly venomous marine species group, the cone snails(Family Conidae), in the shores of Qeshm Island, of evaluating the possibility of envenomation in the area and summarize recommendations for emergency first ***: Shores surrounding Qeshm Island were surveyed to collect cone snails during cold(February and March) and warm(May and June) seasons of 2017. Collected snails were identified to the species level. Abundance and species richness were estimated in shores of different structures, including muddy and sandy-rocky shores. Also, the most updated medical literature was reviewed to summarize related emergency first ***: Three cone snail species were recorded from southern sandy-rocky shores of the Island, in decreasing order of abundance, included crowned cone(Conus coronatus)(65%), feathered cone(Conus pennaceus)(28%), and frigid cone(Conus frigidus)(7%).Abundance of these species were significantly higher in cold season compared to the warm season(P < 0.05). No cone snails were recorded along the northern muddy shores of the ***: Envenomation can cause various symptoms ranging from minor local pain to systemic paralysis and death due to respiratory failure. We recommend an awareness programme for the seashore visiting public.

关键词： Envenomation symptoms Subtropical coastal waters Sandy shores Venom

Dynamic analysis, simulation, and control of a 6-DOF IRB-120 robot manipulator using sliding mode control and boundary layer method

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Journal of Central South University 2018年第9期25卷 2219-2244页

作者： Mojtaba hadi BARHAGHTALAB Vahid MEIGOLI Mohammad Reza GOLBAHAR HAGHIGHI seyyed Ahmad NAYERI Arash EBRAHIMI Department of Electrical Engineering School of Engineering Persian Gulf University Department of Mechanical Engineering School of Engineering Persian Gulf University Department of Communication School of Electrical and Computer Engineering Tehran University Institute of Electrical Power Engineering Faculty of Computer Science and Electrical Engineering IEFRostock University

Because of its ease of implementation,a linear PID controller is generally used to control robotic *** controllers cannot effectively cope with uncertainties and variations in the parameters;therefore,nonlinear controllers with robust performance which can cope with these are *** sliding mode control(SMC)is a robust state feedback control method for nonlinear systems that,in addition having a simple design,efficiently overcomes uncertainties and disturbances in the *** also has a very fast transient response that is desirable when controlling robotic *** most critical drawback to SMC is chattering in the control input *** solve this problem,in this study,SMC is used with a boundary layer(SMCBL)to eliminate the chattering and improve the performance of the *** proposed SMCBL was compared with inverse dynamic control(IDC),a conventional nonlinear control *** kinematic and dynamic equations of the IRB-120 robot manipulator were initially extracted completely and accurately,and then the control of the robot manipulator using SMC was *** validation,the proposed control method was implemented on a 6-DOF IRB-120 robot manipulator in the presence of *** results were simulated,tested,and compared in the MATLAB/Simulink *** further validate our work,the results were tested and confirmed experimentally on an actual IRB-120 robot manipulator.

关键词： robot manipulator control IRB-120 robot sliding mode control sliding mode control with boundary layer inverse dynamic control

The Herpetofauna of Iran: Checklist of Taxonomy, Distribution and Conservation Status

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Asian Herpetological Research 2015年第4期6卷 257-290页

作者： Barbod SAFAEI-MAHROO Hanyeh GHAFFARI hadi FAHIMI Siamak BROOMAND Mahtab YAZDANIAN Elnaz NAJAFI MAJD seyyed Saeed HOSSEINIAN YOUSEFKHANI Elham REZAZADEH Mahboubeh Sadat HOSSEINZADEH Reza NASRABADI Mehdi RAJABIZADEH Meysam MASHAYEKHI Alireza MOTESHAREI Alireza NADERI Seyed Mahdi KAZEMI Pars Herpetologists Institute Department of Environmental Sciences Faculty of Natural Resources University of Kurdistan Department of Biology Faculty of Science Ege University Department of Biology Faculty of Science Ferdowsi University of Mashhad Department of Biology Faculty of Scince Razi University Department of Biodiversity Institute of Science and High Technology and Environmental Sciences Graduate University of Advanced Technology Department of Environment Islamic Azad University Science and Research Natural History Museum of Iran Pardisan Nature Park Department of the Environment Department of Biology College of Sciences Qom Branch Islamic Azad University

We present an annotated checklist for a total 241 reptiles and 22 amphibians including 5 frogs, 9 toads, 7 newts and salamanders, 1 crocodile, 1 worm lizard, 148 lizards, 79 snakes and 12 turtles and tortoises, includes the most scientific literature up to August 2014 and also based on several field surveys conducted in different Provinces of Iran from 2009 to 2014. We present an up-to-dated checklist of reptiles and amphibians in Iran. We provide a comprehensive listing of taxonomy, names, distribution and conservation status of all amphibians and reptiles of Iran. This checklist includes all recognized named taxa, English names for classes, orders, families, species, subspecies along with Persian names for species, including indication of native and introduced species. For the first time we report two non-native introduced reptiles from natural habitats of Iran. Of the total 22 species of amphibians in Iran, 6（27.2%） are endemic and of the total 241 species of reptiles, 55（22.8%） are endemic. Of the 22 amphibians species in Iran, 3（13%） are Critically Endangered, 2（9%） are Vulnerable and of the 241 reptile species 3（1.2%） are Critically Endangered, 4（1.6%） are Endangered and 10（4.1%） are Vulnerable. Accordingly, this paper combines significant aspects of taxonomy, common names, conservation status and distribution of the Iranian herpetofauna.

关键词： Amphibians Anura Caudata Reptiles Crocodylia Squamata Testudines Persian common name

Assessing the Role of Environmental Factors in the Transmission of Infectious Diseases in Communal Spaces

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Journal of Architectural Environment & Structural Engineering Research 2023年第2期6卷 33-44页

作者： seyyed Mohammadmahdi Hosseinikia Negar Khiabanchian hadi Rezaei Rad Architecture Department Tabriz Islamic Art UniversityTabriz***Iran Architecture Department ACECRBranch of HamedanHamedan***Iran Urban Planning Department Buali Sina UniversityHamedan***Iran

Communal spaces provide different facilities for users while they are the primary place for the spread of diseases,especially *** is possible through human behaviors,the way they communicate with each other and breathe in an environment by airborne pathogenic *** from various fields have gained valuable experience and achievements regarding how to prevent these diseases by means of environmental *** to the spread of the corona virus in the past years,environmental planners and designers seriously considered the need to review the design and use of spatial *** study provides a framework for decision making and design of communal spaces based on how environmental components can be effective in preventing the spread of respiratory diseases such as coronavirus and *** research method used in this article is logical reasoning combined with ANP method and focus group *** to the results of this research,indoor air quality plays the most crucial role in preventing the transmission of viruses(contagious respiratory diseases)based on expert groups.

关键词： Well building Healthy building Contagious diseases respiratory Air borne transmission