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Precise Measurement of Moving Object by Moiré-Based Image Processing Technique

Open Journal of Fluid Dynamics 2012年第4期2卷 202-207页

作者： md. Tawhidul Islam Khan Maeda Kazuhiko Kenbu Teramoto md. mahbub hasan Department of Advanced Technology Fusion Saga University Saga Japan Faculty of Science and Engineering Saga University Saga Japan Graduate School of Science and Engineering Saga University Saga Japan

Moiré images that are generally termed as moiré fringes have been generated due to the interference of two repetitive gratings. These patterns can be applied to many uses in metrology such as the measurements of surface profilometry of aerofoil, stress-strain effects, thermal deformation and so on. Moreover, 3D surface reconstruction as well as movement characterization of linearly and rotary moving objects can be visualized and identified by the moiré imaging technique. Recently it is approached as an emerging tool in the fields of biotechnology-particularly in biomechanics, nanotechnology, broadband communication and optoelectronics as well. Conventional Moiré interferometry evaluates the interference of two light waves being reflected on a reference surface and the object to be profiled. However, satisfactions in the requirements for the current significant issues in obtaining accurate measurements regarding the information of the movements as well as the dimensional deformations of objects dealing with the online inspection in micro-level and nano-level are still challenging. Particularly, for the demand of the present real-time auto-inspection of different precise information of movements objects statistically and dynamically. In that case single light wave system makes the moiré sensing system easier and applicable in real-time imaging. Furthermore, avoiding the employment of expensive conventional imaging facilities in 3-D measurement in mechanical as well as bio-mechanical systems has become a critical problem to be tackled. Therefore, research has been conducted focusing on the objective of developing a simple but precise measuring tool based on a single wave moiré imaging technique for multidimensional motion sensing by employing simple image processing approaches. An experimental set-up with a small CMOS camera has been developed capable of measuring the motion of an object by using a simply ink-printed straight optical grating lines attached to the movin

关键词： Moiré Imaging Single Grating Method Precise Measurement

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Energy Harvesting in the Wake of An Inverted C-Shaped Bluff Body

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China Ocean Engineering 2024年第1期38卷 68-80页

作者： WANG Jun-lei LI Shen-fang md.mahbub ALAM ZHU Hong-jun HU Guo-biao School of Mechanical and Power Engineering Zhengzhou UniversityZhengzhou 450000China Center for Turbulence Control Harbin Institute of Technology(Shenzhen)Shenzhen 518055China State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu 610500China Internet of Things Thrust The Hong Kong University of Science and Technology(Guangzhou)Guangzhou 511400China

This paper proposes a novel wake-induced vibration(WIV)-based energy harvesting system consisting of two bluff *** inverted C-shaped bluff body is stationary installed at the upstream position to generate an interference wake street,and a cylinder bluff body equipped with a transducer is elastically suspended at the downstream position to harness WIV *** hydrodynamics and energy harvesting(EH)performance of the proposed system are investigated via experimental *** reduced velocity(U*)ranging from 2 to 14(the corresponding Reynolds number ranging from 15100 to 106200)is considered in the present *** is found that the wake generated by the inverted C-shaped bluff body significantly affects the EH *** the opening angle(α)of the C-shaped bluff body increases the vibration amplitude of the downstream cylinder,thereby increasing the harvested *** the spacing(L)between two bluff bodies is two times the cylinder diameter(D),the wake-induced vibration(WIV)mode is observed,while the combined WIV and wake galloping(WG)mode occurs whenαis 150°,and L equals 3D or *** average drag coefficient becomes negative when L is 2D,3D,or *** carefully configuring a C-shaped bluff body,the wake generated by it can bring an augmenting effect on the vibration of the downstream EH *** example,the RMS power output of the proposed EH system reaches a maximum of 0.31 W at U*=8 and L=4D,which is 300%greater than that of its traditional ***,after a number of case stud-ies,it is identified that the proposed EH system can achieve the best performance whenαis 150°and L=2D.

关键词： wake-induced vibration vortex-induced vibration galloping energy harvesting bluff body

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Design and analysis of high birefringence and nonlinearity with small confinement loss photonic crystal fiber

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Frontiers of Optoelectronics 2019年第2期12卷 165-173页

作者： Rekha SAHA md.mahbub HOSSAIN md. Ekhlasur RAHAMAN Himadri Shekhar MONDAL Electronics and Communication Engineering Discipline Khulna UniversityKhulna 9208Bangladesh

High birefringence with low confinement loss photonic crystal fiber (PCF) has significant advantages in the field of sensing, dispersion compensation devices, nonlinear applications, and polarization filter. In this report, two different models of PCFs are presented and compared. Both the models contain five air holes rings with combination of circular and elliptical air holes arrangement. Moreover, the elliptical shaped air holes polarization and the third ring air holes rotational angle are varied. To examine different guiding characteristics, finite element method (FEM) with perfectly matched layer (PML) absorbing boundary condition is applied from 1.2 to 1.8 |im wavelength range. High birefringence, low confinement loss, high nonlinearity, and moderate disper-sion values are successfully achieved in both the PCFs models. Numeric analysis shows that model-1 gives higher birefringence (2.75 ×10^-2) and negative dispersion (-540.67 ps/(nm ·km)) at 1.55 |im wavelength. However, model-2 gives more small confinement loss than model-1 at the same wavelength. In addition, the proposed design demonstrates the variation of rotation angle has great impact to enhance guiding properties especially the birefringence.

关键词： birefringence dispersion polarization main-taining photonic crystal fiber (PCF) polarization-selective devices polarization

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Structural, Dielectric, and Magnetic Properties of Ba-Doped Multiferroic Bismuth Ferrite

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Acta Metallurgica Sinica(English Letters) 2015年第8期28卷 958-964页

作者： Rubayyat mahbub Takian Fakhrul.md.Fakhrul Islam Mehedi hasan Arman Hussain M.A.Matin M.A.Hakim Department of Glass and Ceramic Engineering Bangladesh University of Engineering and Technology Department of Materials and Metallurgical Engineering Bangladesh University of Engineering and Technology

The main focus of the research was to correlate the microstructure with dielectric and magnetic properties of Bi1-xBaxFeO3 samples. Bi1-xBaxFeO3 samples（x = 0.1, 0.2 and 0.3） were synthesized by the conventional solid-state reaction method using nano-powders of Bi2O3, Fe2O3, and BaCO3. Thereafter, field emission scanning electron microscope and X-ray diffraction（XRD） techniques were used to examine the structure and phase of the samples. Phase analysis by XRD indicated that the single-phase perovskite structure was formed with possible increment in lattice parameter with increasing Ba doping. Complex permeability（u＇iand u＇＇i） measured using impedance analyzer confirmed the increase in magnetic property with increasing Ba doping. Finally, dielectric constant（k） was analyzed as a function of temperature at different frequencies. Dielectric constant as high as 2900 was attained in this research for Bi0.8Ba0.2FeO3 sample due to reduction in leakage current at this composition.

关键词： Multiferroic Bismuth ferrite Dielectric Complex permeability

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Rainfall Prediction Model Improvement by Fuzzy Set Theory

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Journal of Water Resource and Protection 2013年第1期5卷 1-11页

作者： mahbub hasan Xingzhong (Frank) Shi Teferi Tsegaye Nesar U. Ahmed Salam md. mahbubush Khan College of Agriculture Food Sciences and Sustainable Systems Kentucky State University Frankfort USA Department of Civil Engineering Alabama Agricultural and Mechanical University Normal USA Department of Mathematics Alabama Agricultural and Mechanical University Normal USA Department of Computer Science Alabama Agricultural and Mechanical University Normal USA

This paper presents the improvement of the fuzzy inference model primarily developed for predicting rainfall with data from United States Department of Agriculture (USDA) Soil Climate Analysis Network (SCAN) Station at the Alabama Agricultural and Mechanical University (AAMU) Campus for the year 2004. The primary model was developed with Fuzzy variables selected based on the degree of association of different factors with various combinations causing rainfall. An increase in wind speed (WS) and a decrease in temperature (TP) when compared between the ith and (i-1)th day were found to have a positive relation with rainfall. Results of the model showed better performance after introducing the threshold values of 1) relative humidity (RH) of the ith day;2) humidity increase (HI) when compared between the ith and (i-1)th day;and 3) product (P) of increase in wind speed (WS) and decrease in temperature (TP) when compared between the ith and (i-1)th day. In case of the improved model, errors between actual and calculated amount of rainfall (RF) were 1.20%, 2.19%, and 9.60% when using USDA-SCAN data from AAMU campus for years 2003, 2004 and 2005, respectively. The improved model was tested at William A. Thomas Agricultural Research Station (WTARS) and Bragg farm in Alabama to check the applicability of the model. The errors between the actual and calculated amount of rainfall (RF) were 3.20%, 5.90%, and 1.66% using USDA-SCAN data from WATARS for years 2003, 2004, and 2005, respectively. Similarly, errors were 10.37%, 11.69%, and 25.52% when using SCAN data from Bragg farm for years 2004, 2005, and 2006, respectively. The primary model yielded the value of error equals 12.35% using USDA- SCAN data from AAMU campus for 2004. The present model performance was proven to be better than the primary model.

关键词： Fuzzy Sets Prediction Rainfall Water Resources

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Predicting Rainfall Using the Principles of Fuzzy Set Theory and Reliability Analysis

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American Journal of Computational Mathematics 2013年第4期3卷 337-348页

作者： mahbub hasan Salam md. mahbubush Khan Chandrasekhar Putcha Ashraf Al-Hamd.n Chance M. Glenn College of Engineering Technology and Physical Sciences Alabama Agricultural and Mechanical University Normal USA Department of Civil & Environmental Engineering University of Alabama Huntsville USA Department of Civil and Environmental Engineering California State University Fullerton USA Department of Civil Engineering Alabama Agricultural and Mechanical University Normal USA Department of Mathematics Alabama Agricultural and Mechanical University Normal USA

The paper presents occurrence of rainfall using principles of fuzzy set theory and principles of reliability analysis. Both the abstract and the rest of the paper are discussed from these two points of view. First, a fuzzy inference model for predicting rainfall using scan data from the USDA Soil Climate Analysis Network Station at Alabama Agricultural and Mechanical University (AAMU) campus for the year 2004 is presented. The model further reflects how an expert would perceive weather conditions and apply this knowledge before inferring a rainfall. Fuzzy variables were selected based on judging patterns in individual monthly graphs for 2003 and 2004 and the influence of different variables that caused rainfall. A decrease in temperature (TP) and an increase in wind speed (WS) when compared between the ith and (i ? 1)th day were found to have a positive relation with a rainfall (RF) occurrence in most cases. Therefore, TP and WS were used in the antecedent part of the production rules to predict rainfall (RF). Results of the model showed better performance when threshold values for 1) Relative Humidity (RH) of ith day;2) Humidity Increase (HI) between the ith and (i ? 1)th day;and 3) Product (P) of decrease in temperature (TP) and an increase in wind speed (WS) were introduced. The percentage of error was 12.35 when compared the calculated amount of rainfall with actual amount of rainfall. This is followed by prediction of rainfall using principles of reliability analysis. This is done by comparing theoretical probabilities with experimental probabilities for the occurrence of two main events, namely, Relative Humidity (RH) and Humidity Increase (HI) being in between specified threshold values. The experimental values of probability are falling in between μ ? σ and μ + σ for both RH and HI parameters, where μ is the mean value and σ is the standard deviation.

关键词： Fuzzy Sets Prediction Reliability Rainfall Water Resources

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Groundwater Depletion with Expansion of Irrigation in Barind Tract: A Case Study of Tanore Upazila

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Journal of Water Resource and Protection 2012年第8期4卷 567-575页

作者： md. Marufur Rahman A. Q. M. mahbub University of Dhaka

In this paper successive depletion of groundwater level with expansion of groundwater irrigation in Barind Tract has been discussed from mid 1960s to 2010 in the context of Tanore Upazila, which is located in severely drought prone area of northwest Bangladesh. After starting of groundwater irrigation in Bangladesh, it spread rapidly all over the country, and about 80% of agricultural land is now supplied irrigation from groundwater. Availability of irrigation in Barind Tract has revolutionized its agriculture, but groundwater level is successively falling all over the country due to excessive withdrawal, and this process is accelerating due to water withdrawal from major rivers by upstream countries. In northwestern part of Bangladesh groundwater depletion problem is severe because this part is free from seasonal flooding. Only source of recharging of groundwater aquifer in this area is rainfall, but rainfall is also lowest here among the country. In this context, this paper presents the change of groundwater level with the spreading of groundwater irrigation in Barind Tract. Hydrograph analysis, groundwater level mapping, groundwater depletion rate calculation are done from groundwater level observation well data of Bangladesh Water Development Board (BWDB) and Barind Multipurpose Development Authority (Bmd.). Climatic condition is analyzed by calculation of rainfall deviation from the data of Bangladesh Meteorological Department (Bmd.. Focus Group Discussion (FGD) and interviews with farmers and experts of different branches are conducted to understand the nature of problems in the study area. Agricultural pattern, cropping intensity (262% in study area and national intensity is 180%), methods of cultivation, crop variety and yields all show a positive change after starting of groundwater irrigation in mid 1980s, but water level is continuously lowering at the rate of 1.37 ft/y in wet season and 0.72 ft/y in dry season. Water is the main input for agriculture but

关键词： Groundwater Depletion Irrigation Barind Tract Tanore

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Lithological Study and Mapping of Barind Tract Using Borehole Log Data with GIS: In the Context of Tanore Upazila

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Journal of Geographic Information System 2012年第4期4卷 349-357页

作者： md. Marufur Rahman A. Q. M. mahbub Geography and Environment University of Dhaka Dhaka Bangladesh

In this paper the lithological study and mapping of Barind Tract is done by using irrigation boreholes log data in the context of an upazila under Barind Tract in northwest Bangladesh. Northwestern part of Bangladesh is severely drought prone area with lowest yearly rainfall in the country. Before groundwater irrigation only one crop was cultivated in this area in rainy season. After spreading of groundwater irrigation agriculture is flourished here, but groundwater level is severely going down, which is making this area risky for several adverse effect like land subsidence, biodiversity loss etc. Lithology is one of the important factors that affect the recharging of groundwater aquifer of any area. This research mainly based on secondary data. Irrigation boreholes log data are collected from Barind Multipurpose Development Authority (Bmd.), a local authority under the Ministry of Agriculture of Bangladesh government provide irrigation in Barind Tract. A GPS survey is conducted to locate the boreholes in the study area. From the study highest thickness of clay layer found 90 ft and lowest 20 ft, and thickness gradually increase from eastern to western side. Aquifer is located between 20 - 90 ft depth from the surface and direction of aquifer is western to eastern side. Agriculture of study area is totally dependent on groundwater irrigation. Thick layer of clay impede recharging of groundwater table. Due to thick layer of sticky and plastic clay land subsidence risk is low, but it act as aquitard which impede groundwater recharging and increase surface runoff.

关键词： Lithology Barind Tract Borehole Log Tanore

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Interaction of ciprofloxacin hydrochloride with sodium dodecyl sulfate in aqueous/electrolytes solution at different temperatures and compositions

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Chinese Journal of Chemical Engineering 2020年第1期28卷 216-223页

作者： Sk.md.Ali Ahsan md.Ruhul Amin Shamim mahbub Mohammad Robel Molla Shahina Aktar Malik Abdul Rub md.Anamul Hoque Muhammad Nadeem Arshad Mohammed Abdullah Khan Department of Chemistry Jahangirnagar UniversitySavarDhaka 1342Bangladesh Chemistry Department Faculty of ScienceKing Abdulaziz UniversityJeddah-21589Saudi Arabia Center of Excellence for Advanced Materials Research King Abdulaziz UniversityJeddah-21589Saudi Arabia

Interactions of ciprofloxacin hydrochloride(CPFH)with sodium dodecyl sulfate(SDS)were investigated by conductivity measurement in H2O/electrolyte solutions(NaCl,Na2SO4&Na3PO4)over 298.15–318.15 K temperature range(with 5 K interval)considering the human body *** all cases,two critical micelle concentrations(c*)were observed which are increased in the presence of drug and decreased in the presence of salts enunciating the presence of interaction amongst the studied ***(CPFH+SDS)system in the presence of salt,the c*values at 303.15 K and I=0.50 mmol·kg^-1 followed the order:CNaCl>CNa2SO4>***ΔG1,m0 andΔG2,m0values are found to be negative for all systems that show that the micellization process is thermodynamically ***(CPFH+SDS)system in water,theΔHm0&ΔSm0 values reveal that the micellization processes is both entropy dominated in almost all *** the occurrence of electrolytes,ΔHm0 andΔSm0 values indicate that micellization processes are both entropy&enthalpy restricted at upper temperature but it becomes totally entropy dependent at higher *** higher positiveΔSm0 values indicate the enhanced hydrophobic interaction in presence of *** enthalpy-entropy compensation was determined from the linear relationship betweenΔHm0 andΔSm0 values in every *** transfer energies as well as compensation temperature and intrinsic enthalpy were also evaluated and the behaviors were comparable to other biological system.

关键词： Ciprofloxacin hydrochloride Sodium dodecyl sulfate Critical micelle concentration Thermodynamic indices Hydrophobic effect

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Amelioration of Salinity Stress in Maize Seed Germination and Seedling Growth Attributes through Seed Priming

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Open Journal of Soil Science 2018年第5期8卷 137-146页

作者： Lucky Akter Oli Ahmed Fakir md. Khairul Alam mahbub Ul Islam Priyanka Chakraborti md. Jahangir Alam md. Harunur Rashid Mahfuza Begum md. Abdul Kader Department of Agronomy Bangladesh Agricultural University Mymensingh Bangladesh Bangladesh Agricultural Research Institute ARS Satkhira Bangladesh Bangladesh Agricultural Research Institute Gazipur Bangladesh Bangladesh Agricultural Research Institute On-Farm Research Division Patuakhali Bangladesh Global Centre for Environmental Remediation (GCER) University of Newcastle Callaghan Australia

Germination of seeds and growth of seedling respond to seed priming as priming can guard the damage of salinity stress. A study conducted in the net house of the Department of Agronomy, BAU, Mymensingh during the period from November 2012 to April 2013 investigated the ameliorative effect of seed priming on seed germination and seedling attributes of maize under various salinity stress conditions. The experiment consisted of five seed priming and four salinity levels (NaCl) and laid out in a Completely Randomized Design (CRD) with three replications. Seed germination and seedling attributes of maize varied due to salinity stress and priming. The highest seed germination (95.7%) was recorded when no stress was imposed under hydropriming (48 hours). The germination of seeds performed even well (92.3%) when treated with hydropriming (48 hours) and NaCl@0.25 dS·m-1 which was followed by hydropriming (24 hours) under no salinity imposed and NaCl@0.25 dS·m-1 salinity. Hydropriming for 48 hours without salt stress performed the best on number of leaves seedling-1 (8), shoot length (28.2 cm), root length (14.5 cm), fresh weight (100.8 g) and dry weight of seedling (50.3 g). The germination and seedling growth parameters were reduced with the increase in salinity levels irrespective of priming while all seed priming treatments showed ameliorative effects. However, reduction in seed germination and seedling attributes were minimal with hydropriming for 48 hours. The results revealed that priming of maize seeds could be used for amelioration of salinity stress and hydropriming for 48 hours appeared as the best seed priming treatment.

关键词： Germination Halopriming Hydropriming Osmopriming Seedling Attributes

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