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Field experiments to improve the efficacy of gargoor (fish trap) fishery in Kuwait's waters

Chinese Journal of Oceanology and Limnology 2012年第4期30卷 535-546页

作者：陈卫忠 al-BAZ ali BISHOP James M. al-husaini mohsen Mariculture and Fisheries Department Kuwait Institute for Scientific Research P. O. Box 1638Salmiya 22017Kuwait

Fish traps were investigated to understand the effects of season, bait type, trap size, and trap soak time on catch rates, catch composition, and trap loss rates from March 2004 to September 2005, to improve the performance and management of Kuwait＇s gargoor （cage style fish trap） fishery, which used to be the nation＇s most important one in terms of value and landings volume. Catch rates were the highest in April/May （5 8 kg/trap haul） and again in December （7 kg/trap haul）. Bait type and trap size also affected catch rates and species composition. Of the seven baits tested, the best catch rates, 〉5 kg/trap haul, occurred with cuttlefish （Sepia pharaonis）, but wolf-herring （Chiroeentrus dorab） and mullet （Liza klunzingeri） also produced good results （4-5 kg/trap haul）. Within the five tested sizes, the two largest-sized traps captured more fish and larger size fish. Analysis of variance （ANOVA） showed significant differences of catch rate among traps with different baits as well as among traps of different sizes. Duncan test further revealed these differences between two specific baits and sizes. Cluster Analysis of species composition showed more differences among different baits than among different trap sizes. Longer soak times did not result in larger catch rates, but increased trap loss. About 10-day soak time resulted in trap loss 7%, while 40-day soak time could result in a loss of around 20%. Consequently, it is recommended that the gargoor be checked every 10 or fewer days. The average overall catch rate during the study period was lower than that of 1980s （4.5 vs. 5.8 kg/trap haul）, indicating a possible decline offish abundance in Kuwait＇s waters. It is recommended that the number of gargoor fishing boats and gargoors from each boat should be limited to allow stock rehabilitation.

关键词： field experiment fish trap improvement of efficacy catch rate Kuwait

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Speak-Correct: A Computerized Interface for the Analysis of Mispronounced Errors

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Computer Systems Science & Engineering 2022年第12期43卷 1155-1173页

作者： Kamal Jambi Hassanin al-Barhamtoshy Wajdi al-Jedaibi mohsen Rashwan Sherif Abdou Faculty of Computing&Information Technology King Abdulaziz UniversitySaudi Arabia Faculty of Engineering Cairo UniversityEgypt Faculty of Computers Cairo UniversityEgypt

Any natural language may have dozens of *** though the equivalent phonemic formation of the word,if it is properly called in different accents,humans do have audio signals that are distinct from one *** the most common issues with speech,the processing is discrepancies in pronunciation,accent,and *** research study examines the issues of detecting,fixing,and summarising accent defects of average Arabic individuals in English-speaking *** article then discusses the key approaches and structure that will be utilized to address both accent flaws and pronunciation *** proposed SpeakCorrect computerized interface employs a cuttingedge speech recognition system and analyses pronunciation errors with a speech *** a result,some of the most essential types of changes in pronunciation that are significant for speech recognition are performed,and accent defects defining such differences are ***,the suggested technique increases the Speaker’s *** uses 100 h of phonetically prepared individuals to construct a pronunciation instruction *** prerecorded sets are used to train Hidden Markov Models(HMM)as well as weighted graph *** speeches are quite clear and might be considered *** proposed interface is optimized for use with an integrated phonetic pronounced dataset,as well as for analyzing and identifying speech faults in Saudi and Egyptian *** proposed interface detects,analyses,and assists English learners in correcting utterance faults,overcoming problems,and improving their pronunciations.

关键词： Speech recognition computerized interface arabic dialects accent defects acoustic error

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Improving TC drill bit's efficiency and resistance to wear by graphene coating

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Petroleum Research 2022年第4期7卷 430-436页

作者： Reza Taheri mohsen Jalali Ahmed al-Yaseri George Yabesh Petroleum Engineering Department University of WyomingWYUSA Petroleum Engineering Department Tehran Azad UniversityTehranIran Petroleum Engineering Discipline Engineering SchoolEdith Cowan UniversityAustralia

Displaying a two-dimensional pure crystal carbon structure,Graphene is the strongest,yet thinnest substance discovered by *** tungsten carbide(TC)drill bits with graphene to evaluate the effect of graphene on the wear,as well as the rate of penetration of the drilling bit was examined in this *** evaluation approaches were employed:one with employing ANSYS Software and the second by employing atomic pressure chemical vapor deposition(APCVD synthesis)in the laboratory to produce a monolayer graphene *** simultaneous software-based and lab-based testing were performed to increase the credibility of the results and minimize the potential *** the simulation using ANSYS,the maximum shear elastic strain,equivalent elastic strain,equivalent(von mises)stress,total deformation and maximum shear stress were investigated prior and after the gra-phene coating was applied on TC simulated *** deformation was only slightly increased,while the maximum shear elastic strain was almost doubled,reflecting that the bit's wear was significantly reduced after the ***-based APCVD synthesis results showed 34%increase in compressive strength of the coated bit,in comparison to the uncoated *** failure occurred for uncoated bit at 35 MPa,where the coated bit experienced failure at 46.9 *** Von Mises stress test conducted on the coated and uncoated samples also indicated that this stress was 41%less for the coated bit,in comparison to the uncoated ***,two small-scale drilling operations,one using a 1inch graphene-coated TC bit and the other using a 1inch non-coated TC bit,were performed on a granite block,to evaluate the performance of the graphene-coated bit in *** a chosen 120-min time frame,27 consecutive holes could be drilled by the graphene-coated TC bit,while 19 consecutive holes could be drilled by the uncoated TC bit,in identical drilling *** implies a 42%increase in ROP.

关键词： Drill bit's efficiency Graphene-coated ANSYS APCVD Wear reduction Penetration rate

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Optimum allocation of FACTS devices in Fars Regional Electric Network using genetic algorithm based goal attainment

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第4期10卷 478-487页

作者： mohsen GITIZADEH mohsen KalANTAR Center of Excellence for Power System Automation and Operation Department of Electrical Engineering Iran University of Science and TechnologyTehran 16844 Iran

This paper presents a novel approach to find optimum locations and capacity of flexible alternating current transmission system (FACTS) devices in a power system using a multi-objective optimization function. Thyristor controlled series compensators (TCSCs) and static var compensators (SVCs) are the utilized FACTS devices. Our objectives are active power loss reduction, newly introduced FACTS devices cost reduction, voltage deviation reduction, and increase on the robustness of the security margin against voltage collapse. The operational and controlling constraints, as well as load constraints, were considered in the optimum allocation. A goal attainment method based on the genetic algorithm (GA) was used to approach the global optimum. The estimated annual load profile was utilized in a sequential quadratic programming (SQP) optimization sub-problem to the optimum siting and sizing of FACTS devices. Fars Regional Electric Network was selected as a practical system to validate the performance and effectiveness of the proposed method. The entire investment of the FACTS devices was paid off and an additional 2.4% savings was made. The cost reduction of peak point power generation implies that power plant expansion can be postponed.

关键词： Flexible alternating current transmission system (FACTS) devices allocation Multi-objective optimization Geneticalgorithm (GA) Goal attainment

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Effects of porous material on transient natural convection heat transfer of nano-fluids inside a triangular chamber

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Chinese Journal of Chemical Engineering 2020年第5期28卷 1203-1213页

作者： mohsen Izadi Mechanical Engineering Department Faculty of EngineeringLorestan UniversityKhorramabadIran

This study numerically investigates the impact of porous materials,nano-particle types,and their concentrations on transient natural convection heat transfer of nano-fluid inside a porous chamber with a triangular *** governing equations of the two-phase mixture model are separated on the computational domain and solved using the Finite Volume Method,taking into account the Darcy–Brinkman model for porous *** was observed that convection heat transfer inside the triangular chamber consists of three stages named initial,transient,and *** features of each step are provided in *** results suggested that the use of a hybrid nano-fluid(water/aluminum oxide-cooper)inside a porous glass material and an increase in volume fraction of nano-particles have adverse effects on heat transfer *** contrast,as the nano-particle volume fraction of the single nano-fluid(water/aluminum oxide)inside the chamber increased,convection heat transfer rate *** the same time,it was observed that the use of both nano-fluids(single and hybrid)in the porous environment of the aluminum foam could improve convection.

关键词： Transient natural convection Mixture model Darcy-Brinlanan model Rayleigh-Benard instability Triangular chamber

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Orbital electronic heat capacity of hydrogenated monolayer and bilayer graphene

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Chinese Physics B 2017年第2期26卷 375-381页

作者： mohsen Yarmohammadi Young Researchers and Elite Club Kermanshah Branch Islamic Azad University Kermanshah Ira

The tight-binding Harrison model and Green＇s function approach have been utilized in order to investigate the contribution of hybridized orbitals in the electronic density of states（DOS） and electronic heat capacity（EHC） for four hydrogenated structures, including monolayer chair-like, table-like, bilayer AA- and finally AB-stacked graphene. After hydrogenation, monolayer graphene and bilayer graphene are behave as semiconducting systems owning a wide direct band gap and this means that all orbitals have several states around the Fermi level. The energy gap in DOS and Schottky anomaly in EHC curves of these structures are compared together illustrating the maximum and minimum band gaps are appear for monolayer chair-like and bilayer AA-stacked graphane, respectively. In spite of these, our findings show that the maximum and minimum values of Schottky anomaly appear for hydrogenated bilayer AA-stacked and monolayer table-like configurations, respectively.

关键词： hydrogenated monolayer and bilayer graphene Harrison model electronic heat capacity density of states Green's function

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Adaptive Output Feedback Regulation for a Class of Uncertain Feedforward Time-Delay Nonlinear Systems

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Journal of Systems Science & Complexity 2020年第3期33卷 604-621页

作者： BELFEKI mohsen University of Sfax IPEISRoute Menzel ChakerKM 0.5B.P.1172Sfax 3018Tunisia Department of mathematics Alkurmah University collegeTaif UniversitySaudi Arabia

This paper addresses the global output feedback regulation problem for a class of uncertain feedforward time-delay nonlinear *** to the previous works,the nonlinear functions in the class of systems under consideration are dominated by an input-output function multiplied by an unknown parameter and linear unmeasured *** using only one dynamic gain and an appropriate Lyapunov-Krasovskii functionals,it is shown that the closed-loop system is globally asymptotically ***,a numerical example is provided to illustrate the effectiveness of the proposed design scheme.

关键词： Adaptive regulation dynamic gain output feedback uncertain feedforward time-delay systems

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Robust Hybrid Control for Ballistic Missile Longitudinal Autopilot

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Chinese Journal of Aeronautics 2011年第6期24卷 777-788页

作者： WAEL mohsen Ahmeda WAEL mohsen Ahmed QUAN Quan Department of Automatic Control School of Automation Science and Electrical Engineering Beihang University Beijing 100191 China State Key Laboratory of Virtual Reality Technology and Systems Beihang University Beijing 100191 China

This paper investigates the boost phase＇s longitudinal autopilot of a ballistic missile equipped with thrust vector control. The existing longitudinal autopilot employs time-invariant passive resistor-inductor-capacitor （RLC） network compensator as a control strategy, which does not take into account the time-varying missile dynamics. This may cause the closed-loop system instability in the presence of large disturbance and dynamics uncertainty. Therefore, the existing controller should be redesigned to achieve more stable vehicle response. In this paper, based on gain-scheduling adaptive control strategy, two different types of optimal controllers are proposed. The first controller is gain-scheduled optimal tuning-proportional-integral-derivative （PID） with actuator constraints, which supplies better response but requires a priori knowledge of the system dynamics. Moreover, the controller has oscillatory response in the presence of dynamic uncertainty. Taking this into account, gain-scheduled optimal linear quadratic （LQ） in conjunction with optimal tuning-compensator offers the greatest scope for controller improvement in the presence of dynamic uncertainty and large disturbance. The latter controller is tested through various scenarios for the validated nonlinear dynamic flight model of the real ballistic missile system with autopilot exposed to external disturbances.

关键词： ballistic missiles attitude control gain-scheduling optimal tuning-control LQ optimal regulators

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Assessment of mobile and potential mobile trace elements extractability in calcareous soils using different extracting agents

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Frontiers of Environmental Science & Engineering 2020年第1期14卷 109-125页

作者： mohsen Jalali Ziba Hurseresht Department of Soil Science College of AgricultureBu_Ali Sina UniversityHamedanIran

Understanding trace elements mobility in soils,extracting agents,and their relationships with soil components,are essential for predicting their movement in soil profile and availability to plants.A laboratory study was conducted to evaluate extractability of cadmium(Cd),cobalt(Co),copper(Cu),nickel(Ni),and zinc(Zn)from calcareous soils utilizing various extracting agents to be specific CaCU,DTPA,EDTA,HNO3,MgCl2,NaN03,NH4NO3,and *** analysis indicated that DTPA and NH4OAc,HN03 and EDTA,and M gCl2 and NH4NO3 extracting agents yielded comparative values,whereas NaN03 and CaCl2 have shown different behavior than other extracting agents for all studied trace *** speciationof extracted trace elements in solutions indicated that in the CaCl2,NaN03,NH4NO3,and MgCl2 extracting agents most extracted Cd,Co,Ni,Zn,and part f Cu were as free ions and may be re-adsorbed on soils,leading to lower extractability,whereas,in the caseof HNO3 extracting agent,the likelihoodof re-adsorptionof trace elements may be *** resultsof speciationof trace elements using NH4OAc DTPA,and EDTA extracting agents showed that Me-(Acetate)3,Me-(Acetate)2(aq),Me(DTPA)3-3-,Me(EDTA)2-.and MeH(EDTA)-complexes dominated in solutions indicating that the extracted trace elements may not be re-adsorbed on soils,leading to higher *** resultsof this study are useful for short and long-term evaluationsof trace elements mobility and further environmental impacts.

关键词： Mobility Calcareous soils Extracting agents Trace elements

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Overview of grid-connected two-stage transformer-less inverter design

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Journal of Modern Power Systems and Clean Energy 2018年第4期6卷 642-655页

作者： mohsen SHAYESTEGAN Department of Electric Electronic and system EngineeringFaculty of Engineering and Built Environment Universiti Kebangsaan Malaysia

This paper gives an overview of previous studies on photovoltaic(PV) devices, grid-connected PV inverters,control systems, maximum power point tracking(MPPT)control strategies, switching devices and transformer-less inverters. The literature is classified based on types of PV systems, DC/DC boost converters and DC/AC inverters,and types of controllers that control the circuit to ensure maximum power tracking and stabilization of load and input voltage. This is followed by the theoretical background of PV devices, an overview of MPPT controllers and common mode leakage current, and a detailed investigation of different inverter topologies regarding the ground leakage current. Furthermore, design principles of power converters, such as DC/DC boost converters, and single-phase inverters are discussed. The paper also discusses limitations and benefits in addition to the basic operating principles of several topologies. Finally, the proposed system is derived and its simulation results are discussed to offer the next generation of grid connected PV systems.

关键词： Transformer-less inverter DC/DC boost converter Maximum power point tracking(MPPT) controller Grid connected photovoltaic(PV) system

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