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Journal of Mountain Science 2009年第1期6卷 1-13页

作者： md.rafiqul islam Department of Physics and Earth Sciences University of the RyukyusOkinawa 903-0213 Japan

The Liquine-Ofqui Fault Zone(LOFZ) of southern Chilean Andes is one of the largest active strike-slip fault *** is an ongoing debate regarding the origin of the stress field along the LOFZ due to its complex *** paper represents a study of the origins of the LOFZ regional stress *** fields are calculated by finite element(FE) *** two possible stress origins, i.e., oblique plate convergence and ridge collision/indenter tectonics of Chile ridge against Peru-Chile trench, have been emphasized in the present *** types of boundary conditions for the three particular models have been applied to calculate stress *** are assumed to be elastic and plane stress *** results are presented in terms of four parameters, i.e., orientation of maximum horizontal stress(σ H max ), displacement vector, s train distribution, and maximum shear stress(τmax ) contour line within the *** results of the first model with oblique plate convergence show inconsistency between the geometric shape of the LOFZ and the distribution of the four *** more realistic results are obtained from the second model with normal ridge collision, there are few coincident in the LOFZ geometry and regional stress *** third model with normal and oblique ridge collision is reasonable in understanding the origin of stress field and geometrical condition in the lithosphere of the LOFZ.

关键词： Liquine-Ofqui Fault Zone FE analysis Elastic rheology Oblique plate convergence Ridgecollision.

Optimization of Slope Angle and Its Seismic Stability: A Case Study for the Proposed Open Pit Coalmine in Phulbari,NW Bangladesh

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Journal of Mountain Science 2013年第6期10卷 976-986页

作者： md.rafiqul islam Mohammed Omar FARUQUE Department of Petroleum & Mining Engineering Shahjalal University of Science & Technology

The present study reflects upon the results of substantial program of two-dimensional Finite Element Method （FEM） numerical analyses of the open pit that links to slope angle optimization associated with the safety factor of the pit slope of a coal mine in Bangladesh. In the present analyses, two types of models have been presented. The first model estimates safety factor without seismic effect on the overall pit slope of the model; the second model incorporates safety factor with seismic stability of the model. The calculated optimum slope angle of the first model is 31% with a rational safety factor of 1.51, prior to the seismic effect. However, the value is reduced to 0.93, 0.82, and 0.72, after we applies the seismic effect in the second model with M6, M6.5, and M7, respectively. Finally, our modeling results emphasize that for the case of the proposed Phulbari coalmine, there is extremely high prospect for causing massive slope failure along the optimum pit slope angle with 31% if the mine area felt seismic shaking, like the Sikkim （in northern India） earthquake with M6.9 on September 18, 2011.

关键词： Open pit coalmine Optimum slope angle Safety factor Seismic stability

Improved voltage tracking of autonomous microgrid technology using a combined resonant controller with lead-lag compensator adopting negative imaginary theorem

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Protection and Control of Modern Power Systems 2022年第1期7卷 149-164页

作者： md.Yah-Ya Ul Haque md.Rashidul islam Tanvir Ahmed md.rafiqul islam Sheikh Department of Electrical and Electronic Engineering Varendra UniversityRajshahi 6204Bangladesh Department of Electrical and Electronic Engineering Rajshahi University of Engineering&TechnologyRajshahi 6204Bangladesh

Growing application of distributed generation units at remote places has led to the evolution of microgrid(MG)*** an MG system functions independently,i.e.,in autonomous mode,unpredictable loads and uncertainties emerge throughout the *** obtain stable and flexible operation of an autonomous MG,a rigid control mechanism is *** this paper,a robust high-performance controller is introduced to improve the performance of voltage tracking of an MG system and to eliminate stability problems.A combination of a resonant controller and a lead-lag compensator in a positive position feedback path is designed,one which obeys the negative imaginary(NI)theorem,for both single-phase and three-phase autonomous MG *** controller has excellent tracking *** is investigated through considering various uncertainties with different load *** feasibility and effectiveness of the controller are also determined with a comparative analysis with some well-known controllers,such as linear quadratic regulator,model predictive and NI approached resonant *** confirms the superi-ority of the designed controller.

关键词： Negative imaginary theorem Resonant controller Lead-lag compensator Autonomous microgrid Voltage tracking

Development of Wi-Fi Based Home Energy Monitoring System for Green Internet of Things

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Journal of Electronic Science and Technology 2016年第3期14卷 249-256页

作者： Mohamed Hadi Habaebi Qazi Mamoon Ashraf Amir Alif Bin Azman md.rafiqul islam the Department of Electrical and Computer Engineering International Islamic University MalaysiaKuala Lumpur 50728Malaysia the Digital Communication Lab Telekom Research and DevelopmentCyberjaya 63000Malaysia

Green Internet of things （loT） has been heralded as the ＂next big thing＂ waiting to be realized in energy-efficient ubiquitous computing. Green IoT revolves around increased machine-to-machine communications and encompasses energy-efficient wireless embedded sensors and actuators that assist in monitoring and controlling home appliances. Energy efficiency in home applications can be achieved by better monitoring of the specific energy consumption by the appliances. There are many wireless standards that can be adopted for the design of such embedded devices in loT. These communication technologies cater to different requirements and are classified as the short-range and long-range ones. To select the best communication method, this paper surveys various loT communication technologies and discusses the advantages and disadvantages to develop an energy monitoring system. An IoT device based on the Wi-Fi technology system is developed and tested for usage in the home energy monitoring environment. The performance of this system is then evaluated by the measurement of power consumption metrics. In the efficient deep-sleep mode, the system saves up to 0.3 W per cycle with an average power dissipation of less than 0.1 W/s.

关键词： Index Terms- Energy efficiency energy monitoring Internet of things.

Impact of Action Observation Therapy along with Usual Physiotherapy Intervention of Individual with Alzheimer’s Disease

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Advances in Alzheimer's Disease 2024年第1期13卷 1-10页

作者： Zahid Bin Sultan Nahid Faruq Ahmed Tuhin Ahammed md Kutub Uddin md Sirazul islam S M Maruf Hossain Sajib md.rafiqul islam Department of Physiotherapy Saic College of Medical Science and Technology Mirpur Bangladesh Department of Physiotherapy Centre for the Rehabilitation of the Paralysed (CRP) Savar Bangladesh Department of Physiotherapy Centre for the Rehabilitation of the Paralysed (CRP) Mymensingh Bangladesh Department of Physiotherapy Centre for the Rehabilitation of the Paralysed (CRP) Mirpur Bangladesh Department of Physiotherapy State College of Health Sciences Dhaka Bangladesh

Alzheimer’s disease (AD) is a neurodegenerative disorder characterized by cognitive impairments in the initial stage, which lead to severe cognitive dysfunction in the later stage. Action observation therapy (AOT) is a multisensory cognitive rehabilitation technique where the patient initially observes the actions and then tries to perform. The study aimed to examine the impact of AOT along with usual physiotherapy interventions to reduce depression, improve cognition and balance of a patient with AD. A 67 years old patient with AD was selected for this study because the patient has been suffering from depression, dementia, and physical dysfunction along with some other health conditions like diabetes and hypertension. Before starting intervention, a baseline assessment was done through the Beck Depression Inventory (BDI) tool, the Mini-Cog Scale, and the Berg Balance Scale (BBS). The patient received 12 sessions of AOT along with usual physiotherapy interventions thrice a week for four weeks, which included 45 minutes of each session. After four weeks of intervention, the patient demonstrated significant improvement in depression, cognition, and balance, whereas the BDI score declined from moderate 21/63 to mild 15/63 level of depression. The Mini-Cog score improved from 2/5 to 4/5, and the BBS score increased from 18/56 to 37/56. It is concluded that AOT along with usual physiotherapy intervention helps to reduce depression, improve cognition and balance of people with AD.

关键词： Alzheimer’s Disease Action Observation Therapy Physiotherapy Intervention

Cohesive Strength and Seismogenic Stress Pattern along the Active Basement Faults of the Precordillera-Sierras Pampeanas Ranges,Western Argentina:An Experimental Analysis by Means of Numerical Model

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Journal of Mountain Science 2009年第4期6卷 331-345页

作者： md. rafiqul islam Department of Physics and Earth Sciences Faculty of ScienceUniversity of the Ryukyus

A two-dimensional finite element method （FEM） model that incorporates faults, elastic rock physical properties, topographical load due to gravity and far-field plate velocity boundary conditions was used to recognize the seismogenic stress state along the fold-and-thrust belt of the Precordillera-Sierras Pampeanas ranges of western Argentina. A plane strain model with nine experiments was presented here to examine the fault strength with two major rock phyical properties： cohesion and angle of internal friction. Mohr-Coulomb failure criterion with bulk rock properties were applied to analyse faults. The stress field at any point of the model was assumed to be comprised of gravitational and tectonic components. The analysis was focused to recognize the seismogenic shear strain concentrated in the internal-cristaline domain of the orogene shown by the modeling. Modeling results are presented in terms of four parameters, i. e., （i） distributions, orientations, and magnitudes of principal stresses （σ1 and σ3）, （ii） displacement vector1 （iii） strain distribution, and （iv） maximum shear stress （τmax） contour line within the model. The simulation results show that the compressive stress is distributed in and around the fault systems. The overall orientation of of σ1 is in horizontal directions, although reorientations do occur within some stress weaker parts, especially subsequent to the faults. A large-scale shear stress is accumulating along the active faults of Tapias-Villicum Fault （TVF）, Salinas-Berros Fault （SBF）, Ampacama-Niquizanga Fault （ANF） and Las Charas Fault （CF）, which could act as local stress and strain modulators to localize the earthquakesoccurrence.

关键词： Finite element method Rock physical property Fold-and-thrust belt Fault strength Seismogenic shear stress pattern

MOVPE Growth of In_xGa_(1-x)N(x～0.4) and Fabrication of Homo-junction Solar Cells

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Journal of Materials Science & Technology 2013年第2期29卷 128-136页

作者： md. rafiqul islam md. Rejvi Kaysir md. Jahirul islam A. Hashimoto A. Yamamoto Department of Electrical and Electronic Engineering KUETKhulna 9203 Bangladesh Graduate School of Engineering University of Fukui 3-9-1 BunkyoFukui 910-8507 Japan

The metal organic vapor phase epitaxy （MOVPE） growth of indium gallium nitride （InGaN） has been discussed in detail towards the fabrication of solar cell. The InGaN film with In contents up to 0.4 are successfully grown by controlling the fundamental growth parameters such as the precursor gas flow rates, temperature etc. The formation of metallic In originates from the higher value （0.74） of trimethylindium/ （trimethylindium ＋ triethylgallium）（TMI/（TMI ＋ TEG）） molar ratio with low （4100） V/lll weight molar ratio while the lower value （0.2） of TMI/（TMI ＋ TEG） causes the phase separation. It is also necessary to control the growth rate and epitaxial film thickness to suppress the phase separation in the material. The crystalline quality of grown films is studied and it is found to be markedly deteriorated with increasing In content. The lattice parameters as well as the thermal expansion coefficient mismatch between GaN template and InGaN epi-layer are primarily considered as the reasons to deteriorate the film quality for higher In content. By using Ino.16Ga0.84N films, an n＋-p homo-junction structure is fabricated on 0.65 μm GaN template. For such a device, the response to the light illumination （AM 1.5） is observed with an open circuit voltage of 1.4 V and the short circuit current density of 0.25 mA/cm2. To improve the performance as well as increase solar photon capturing, the device is further fabricated on thick GaN template with higher In content. The In0.25Ga0.75N n＋-p junction solar cell is found better performance with an open circuit voltage of 1.5 V and the short circuit current density of 0.5 mA/cm2. This is the InGaN p-n homo-junction solar cell with the highest In content ever reported by MOVPE.

关键词： InGaN Metal organic vapor phase epitaxy (MOVPE) Growth Film quality Doping p-n junction

Determining asphalt surface temperature using weather parameters

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Journal of Traffic and Transportation Engineering(English Edition) 2019年第6期6卷 577-588页

作者： Zafrul H.Khan md Rashadul islam rafiqul A.Tarefder Department of Civil Engineering University of New MexicoAlbuquerqueNM 87131USA Civil Engineering Technology Colorado State University-PuebloPuebloCO 81001USA

Temperature affects the structural response of asphalt concrete(AC) pavement To evaluate the performance,it is important to accurately predict the pavement surface *** study develops three regression models to determine the surface temperature of an asphalt pavement using field measured data such as air temperature,wind speed,wind direction,relative humidity,and solar *** models namely,24-h model,day-time model and night-time model were developed based on one-year continuous *** weather data were measured from October 2012 to October 2013 at an instrumented pavement section on Interstate I-40 near Albuquerque,New *** developed regression models were validated using October 2014 to June 2015 weather data,which were not used in developing the regression *** temperatures predicted using the developed regression models were then compared to those predicted using the pavement mechanistic-empirical(ME) software’s default *** is observed that the regression models are better predictors of pavement surface temperatures than the ME default models.A parametric study was also performed in this study to identify the effects of weather parameters on the pavement surface temperature *** authors of this study expect that this study will be useful in pavement design especially in cold regions.

关键词： Asphalt pavement Air temperature Surface temperature Wind Relative humidity Solar radiation

Anomaly Detection in ICS Datasets with Machine Learning Algorithms

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Computer Systems Science & Engineering 2021年第4期37卷 33-46页

作者： Sinil Mubarak Mohamed Hadi Habaebi md.rafiqul islam Farah Diyana Abdul Rahman Mohammad Tahir International islamic University Malaysia Jalan Gombak53100Malaysia Sunway University Selangor47500Malaysia

An Intrusion Detection System (IDS) provides a front-line defensemechanism for the Industrial Control System (ICS) dedicated to keeping the process operations running continuously for 24 hours in a day and 7 days in a week.A well-known ICS is the Supervisory Control and Data Acquisition (SCADA)system. It supervises the physical process from sensor data and performs remotemonitoring control and diagnostic functions in critical infrastructures. The ICScyber threats are growing at an alarming rate on industrial automation applications. Detection techniques with machine learning algorithms on public datasets,suitable for intrusion detection of cyber-attacks in SCADA systems, as the firstline of defense, have been detailed. The machine learning algorithms have beenperformed with labeled output for prediction classification. The activity trafficbetween ICS components is analyzed and packet inspection of the dataset is performed for the ICS network. The features of flow-based network traffic areextracted for behavior analysis with port-wise profiling based on the data baseline,and anomaly detection classification and prediction using machine learning algorithms are performed.

关键词： Industrial control system SCADA intrusion detection system machine learning anomaly detection

Characterization of subgrade soil mixed with recycled asphalt pavement

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Journal of Traffic and Transportation Engineering(English Edition) 2018年第3期5卷 207-214页

作者： md Mehedi Hasan md Rashadul islam rafiqul A.Tarefder Department of Civil Engineering University of New Mexico Civil Engineering Technology Colorado State University-Pueblo

Due to awareness to greener environment, use of recycled asphalt material has become popular in asphalt pavement industry. The use of recycled asphalt pavement （RAP） ma- terials in subgrade soil can be an additional scope of utilizing RAP. This study investigates the effect of RAP on the resilient modulus （MR） of subgrade soils mixed with RAP materials. Note that MR is the principal material input parameter for designing asphalt pavement using the recent mechanistic-empirical pavement design software. As a first step of the current study, different percentages of RAP and moisture were thoroughly mixed with subgrade soils. Then, the MR of these RAP mixed soils were determined using the AASHTO T 307 （1999） at different stress levels in the laboratory. Results show that the MR of RAP mixed soil increases with the applied deviatoric and bulk stresses, however, it is less sensitive to applied confining pressure. Use of RAP materials has made the soils stiff enough not to respond to the confining pressure. As expected, the MR value reaches a maximum at the optimum moisture content and increases linearly with RAP content. The MR values and characteristics of the RAP mixed subgrade soils, as determined by the current study, can be used for subgrade design and stabilization using RAP for better pavement design.

关键词： Subgrade Recycled asphalt pavement Moisture Resilient modulus Stress