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Chaos suppression of uncertain gyros in a given finite time

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Chinese Physics B 2012年第11期21卷 126-131页

作者： mohammad Pourmahmood Aghababa hasan Pourmahmood Aghababa Electrical Engineering Department Urmia University of Technology Department of Mathematics University of Tabriz Research Center for Industrial Mathematics of University of Tabriz

The gyro is one of the most interesting and everlasting nonlinear dynamical systems, which displays very rich and complex dynamics, such as sub-harmonic and chaotic behaviors. We study the chaos suppression of the chaotic gyros in a given finite time. Considering the effects of model uncertainties, external disturbances, and fully unknown parameters, we design a robust adaptive finite-time controller to suppress the chaotic vibration of the uncertain gyro as quickly as possible. Using the finite-time control technique, we give the exact value of the chaos suppression time. A mathematical theorem is presented to prove the finite-time stability of the proposed scheme. The numerical simulation shows the efficiency and usefulness of the proposed finite-time chaos suppression strategy.

关键词： chaos suppression chaotic gyro finite-time stability robustness

Hormone replacement therapy for menopausal mood swings and sleep quality:The current evidence

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World Journal of Psychiatry 2024年第10期14卷 1605-1610页

作者： Sanja Borozan Abul Bashar M Kamrul-hasan Joseph M Pappachan Department of Endocrinology Clinical Centre of MontenegroPodgorica 81000Montenegro Faculty of Medicine University of MontenegroPodgorica 81000Montenegro Department of Endocrinology Mymensingh Medical College HospitalMymensingh 2200DhakaBangladesh Department of Endocrinology and Metabolism Lancashire Teaching Hospitals NHS TrustPreston PR29HTUnited Kingdom Faculty of Science Manchester Metropolitan UniversityManchester M156BHUnited Kingdom Department of Endocrinology Kathmandu Medical CollegeManipal UniversityManipal 576104India

Marked alterations in the normal female hormonal milieu in the perimenopausal period significantly affect women’s health,leading to decreased well-being,psychological distress,and impaired quality of *** menopausal symp-toms include hot flashes,sleep and mood changes,fatigue,weight gain,and urogenital *** often neglect mood swings and disrupted sleep,although those can significantly limit the productivity of women and impair their cognitive function and mental ***-based management should include a personalized,holistic approach to alleviate symptoms and careful consideration of the risks vs benefits of hormone replacement therapy(HRT),with due consideration of personal preferences.A research paper in the recent issue of the World Journal of Psychiatry by Liu et al investigated the role of HRT in altering mood changes and impaired sleep quality in menopausal women,which helps us to understand the benefits of this treatment approach.

关键词： Menopausal symptoms Mood changes Sleep quality Hormone replacement therapy Quality of life

Impact of climate change on hydropower generation in Rio Jubones Basin, Ecuador

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Water Science and Engineering 2018年第2期11卷 157-166页

作者： mohammad Mehedi hasan Guido Wyseure Hydraulic Research Directorate River Research Institute Department of Earth and Environmental Sciences KU Leuven

This study attempted to use the soil and water assessment tool(SWAT), integrated with geographic information systems(GIS), for assessment of climate change impacts on hydropower generation. This methodology of climate change impact modeling was developed and demonstrated through application to a hydropower plant in the Rio Jubones Basin in Ecuador. ArcSWAT 2012 was used to develop a model for simulating the river flow. The model parameters were calibrated and validated on a monthly scale with respect to the hydro-meteorological inputs observed from 1985 to 1991 and from 1992 to 1998, respectively. Statistical analyses produced Nash-Sutcliffe efficiencies(NSEs) of 0.66 and 0.61 for model calibration and validation, respectively, which were considered acceptable. Numerical simulation with the model indicated that climate change could alter the seasonal flow regime of the basin, and the hydropower potential could change due to the changing climate in the *** analysis indicates that, though the hydropower generation will increase in the wet season, the plant will face a significant power shortage during the dry season, up to 13.14% from the reference scenario, as a consequence of a 17% reduction of streamflow under an assumption of a 2.9℃ increase in temperature and a 15% decrease in rainfall. Overall, this study showed that hydrological processes are realistically modeled with SWAT and the model can be a useful tool for predicting the impact of climate change.

关键词： SWAT Hydropower generation Climate change Sensitivity analysis Nash-Sutcliffe efficiency(NSE)

Plant Nitrogen Metabolism: Balancing Resilience to Nutritional Stress andAbiotic Challenges

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Phyton-International Journal of Experimental Botany 2024年第3期93卷 581-609页

作者： Muhammad Farhan Manda Sathish Rafia Kiran Aroosa Mushtaq Alaa Baazeem Ammarah Hasnain Fahad Hakim Syed Atif hasan Naqvi Mustansar Mubeen Yasir Iftikhar Aqleem Abbas Muhammad Zeeshan Hassan Mahmoud Moustafa Department of Plant Pathology Faculty of Agricultural Sciences&TechnologyBahauddin Zakariya UniversityMultan60800Pakistan Centro de Investigación de Estudios Avanzados del Maule(CIEAM) Vicerrectoría de Investigación y PostgradoUniversidad Católica del MauleTalca3460000Chile College of Food Science and Nutritional Engineering China Agricultural UniversityBeijingChina Department of Biology College of ScienceTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Department of Biotechnology Faculty of Biological SciencesLahore University of Biological and Applied SciencesLahorePakistan Department of Plant Pathology College of AgricultureUniversity of SargodhaSargodha40100Pakistan Department of Agriculture and Food Technology Karakorum International UniversityGilgitPakistan Department of Biology Faculty of ScienceKing Khalid UniversityAbhaSaudi Arabia

Plant growth and resilience to abiotic stresses,such as soil salinity and drought,depend intricately on nitrogen *** review explores nitrogen’s regulatory role in plant responses to these challenges,unveiling a dynamic interplay between nitrogen availability and abiotic *** the context of soil salinity,a nuanced rela-tionship emerges,featuring both antagonistic and synergistic interactions between salinity and nitrogen ***-induced chlorophyll depletion in plants can be alleviated by optimal nitrogen supplementation;however,excessive nitrogen can exacerbate salinity *** delve into the complexities of this interaction and its agri-cultural ***,a vital element within essential plant structures like chloroplasts,elicits diverse responses based on its *** review comprehensively examines manifestations of nitrogen deﬁciency and toxicity across various crop types,including cereals,vegetables,legumes,and ***,we explore the broader consequences of nitrogen products,such as N_(2)O,NO_(2),and ammonia,on human ***-ing the intricate relationship between nitrogen and salinity,especially chloride accumulation in nitrate-fed plants and sodium buildup in ammonium-fed plants,is pivotal for optimizing crop nitrogen ***,prudent nitrogen use is essential,as overapplication can exacerbate nitrogen-related *** Use Efﬁ-ciency(NUE)is of paramount importance in addressing salinity challenges and enhancing sustainable crop *** this goal requires advancements in crop varieties with efﬁcient nitrogen utilization,pre-cise timing and placement of nitrogen fertilizer application,and thoughtful nitrogen source selection to mitigate losses,particularly urea-based fertilizer *** review article delves into the multifaceted world of plant nitrogen metabolism and its pivotal role in enabling plant resilience to nutritional stress and abiotic chall

关键词： Synthetic nitrogen nitrogen signaling sustainable agriculture eutrophication ammonium nitrate

Role of Double Oxide Film Defects in the Formation of Gas Porosity in Commercial Purity and Sr-containing Al Alloys

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Journal of Materials Science & Technology 2014年第2期30卷 154-162页

作者： Batool Farhoodi Ramin Raiszadeh mohammad-hasan Ghanaatian Department of Metallurgy and Materials Science and Mineral Industries Research Centre Shahid Bahonar University of Kerman

The role of double oxide film （bifilm） defects in the formation of gas porosity in commercial purity and Srcontaining AI alloys was investigated by means of a reduced pressure test （RPT） technique. The liquid metal was poured from a height into a crucible to introduce oxide defects into the melt. The melt was then subjected to different ＂hydrogen addition＂ and ＂holding in liquid state＂ regimes before RPT samples were taken. The RPT samples were then characterized by determining their porosity parameters and examining the internal surfaces of the pores formed in them by scanning electron microscopy. The results indicated oxide defects as the initiation sites for the growth of gas porosity, both in commercial purity and Sr-containing AI alloys. The results also rejected reduction of the surface tension of the melt, increase in the volumetric shrinkage and reduction in interdendritic feeding as the possible causes of an increase in the porosity content of the AI castings modified with strontium. The change in the composition of the oxide layers of double oxide film defects was suggested to be responsible for this behaviour.

关键词： Double oxide film defects Bifilm Strontium Modification Porosity Aluminium casting

Crack Propagation in Pipelines Under Extreme Conditions of Near-Neutral PH SCC

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Computers, Materials & Continua 2022年第12期73卷 5315-5329页

作者： Abdullah Alsit mohammad Alkhedher hasan Hamdan Mechanical Engineering Department College of EngineeringAbu Dhabi UniversityAbu Dhabi59911United Arab Emirates

Stress Corrosion Cracking(SCC)process through which cracks occur in a variety of susceptible materials is a result of a combination of residual or applied stresses and *** oil and gas field,buried pipeline steels are made of low-alloy steels with a ferritic-pearlitic structure,such as *** dilute solutions,these materials are prone to SCC *** Near-neutral simulated soil solution(NS4)solution is established to imitate SCC conditions and subsequently became the industry requirement for crack growth experiments in the majority of *** strainassisted active crack pathways are considered while modelling SCC growth as an oxide film rupture and anodic dissolution ***’s been hypothesized that increasing the strain concentration can help with dissolution at the filmfree crack *** research focuses on estimating the SCC crack growth rate under various environmental conditions in oil and gas pipelines using finite element *** simulation is carried out using the J-integral theory in the COMSOL Multiphysics *** are performed to model the crack growth rate(CGR)using slip anodic dissolution(film rupture)*** plastic strain gradient is required to compute the SCC CGR(da/dt).Because the plastic strain located at crack tip increases proportionally to the crack length as it propagates,the CGR increases as the stress intensity factor(SIF)*** crack growth rates increase when constant loads are applied and as the temperature rises,and elevating the cathodic potential has a minimal influence on the propagation rate of cracks but raises the material yield strength and imparts brittle behavior to it.

关键词： Stress corrosion cracking SCC oxide film rupture and anodic dissolution crack growth rate CGR J-integral stress intensity factor SIF

Heat and Mass Transfer on Non-Newtonian Peristaltic Flow in a Channel in Presence of Magnetic Field: Analytical and Numerical Analysis

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Applied Mathematics 2024年第8期15卷 568-583页

作者： Md. Maruf hasan Md. Enamul Karim Md. Abdus Samad Department of Mathematics Comilla University Comilla Bangladesh Department of Applied Mathematics University of Dhaka Dhaka Bangladesh

A study has been arranged to investigate the flow of non-Newtonian fluid in a vertical asymmetrical channel using peristalsis. The porous medium allows the electrically conductive fluid to flow in the channel, while a uniform magnetic field is applied perpendicular to the flow direction. The analysis takes into account the combined influence of heat and mass transfer, including the effects of Soret and Dufour. The flow’s non-Newtonian behavior is characterized using a Casson rheological model. The fluid flow equations are examined within a wave frame of reference that has a wave velocity. The analytic solution is examined using long wavelengths and a small Reynolds number assumption. The stream function, temperature, concentration and heat transfer coefficient expressions are derived. The bvp4c function from MATLAB has been used to numerically solve the transformed equations. The flow characteristics have been analyzed using graphs to demonstrate the impacts of different parameters.

关键词： Stream Function Mass Transfer Vertical Channel Casson Fluid

Innovative Developments in HCI and Future Trends

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International Journal of Automation and computing 2017年第1期14卷 10-20页

作者： mohammad S.hasan Hongnian Yu Faculty of Computing Engineering and Sciences Staffordshire University Faculty of Science and Technology Bournemouth University

The recent developments in technology have made noteworthy positive impacts on the human-computer interaction （HCI）. It is now possible to interact with computers using voice commands, touchscreen, eye movement, hand gesture, etc. This paper compiles some of the innovative HCI progresses in various areas, e.g., specialised input/output devices, virtual or augmented reality, wearable technology, etc. It also identifies some future research directions.

关键词： Human-computer interaction (HCI) virtual reality augmented reality haptic feedback controller smart-home.

Artinianness and Attached Primes of Formal Local Cohomology Modules

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Algebra Colloquium 2014年第2期21卷 307-316页

作者： mohammad hasan Bijan-Zadeh Shahram Rezaei Department of Mathematics Faculty of Science Payame Noor University Iran

Let a be an ideal of a local ring （R, m） and A4 a finitely generated R-modu｜e. In this paper we study the Artinianness properties of formal local cohomology modules and we obtain the lower and upper bounds for Artinianness of formal local cohomology modules. Additionally, we determine the set AttR a dim M（M） and we show that the set of all non-isomorphic formal local cohomology modules a dim M（M） is finite.

关键词： Artinianness properties attached primes formal local cohomology local co-homology