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Vehicle-Bridge Interaction Simulation and Damage Identification of a Bridge Using Responses Measured in a Passing Vehicle by Empirical Mode Decomposition Method

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Open Journal of Civil Engineering 2023年第4期13卷 742-755页

作者： Shohel rana md. Rifat Zaman md. Ibrahim Islam Ifty Seyedali Mirmotalebi Tahsin Tareque Department of Civil Engineering Bangladesh University of Engineering and Technology Dhaka Bangladesh Department of Civil Engineering Atish Dipankar University of Science & Technology Dhaka Bangladesh Department of Civil Architectural and Environmental Engineering North Carolina Agricultural and Technical State University Greensboro North Carolina USA Department of Civil Engineering University of Texas Rio Grande Valley Edinburg Texas USA

To prevent early bridge failures, effective Structural Health Monitoring (SHM) is vital. Vibration-based damage assessment is a powerful tool in this regard, as it relies on changes in a structure’s dynamic characteristics as it degrades. By measuring the vibration response of a bridge due to passing vehicles, this approach can identify potential structural damage. This dissertation introduces a novel technique grounded in Vehicle-Bridge Interaction (VBI) to evaluate bridge health. It aims to detect damage by analyzing the response of passing vehicles, taking into account VBI. The theoretical foundation of this method begins with representing the bridge’s superstructure using a Finite Element Model and employing a half-car dynamic model to simulate the vehicle with suspension. Two sets of motion equations, one for the bridge and one for the vehicle are generated using the Finite Element Method, mode superposition, and D’Alembert’s principle. The combined dynamics are solved using the Newmark-beta method, accounting for road surface roughness. A new approach for damage identification based on the response of passing vehicles is proposed. The response is theoretically composed of vehicle frequency, bridge natural frequency, and a pseudo-frequency component related to vehicle speed. The Empirical Mode Decomposition (Emd) method is applied to decompose the signal into its constituent parts, and damage detection relies on the Intrinsic Mode Functions (IMFs) corresponding to the vehicle speed component. This technique effectively identifies various damage scenarios considered in the study.

关键词： Structural Health Monitoring Vibration-Based Damage Identification Vehicle-Bridge Interaction Finite Element Model Empirical Mode Decomposition

Performance Evaluation &Operation of DSP Control UPS System

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Engineering（科研） 2020年第9期12卷 666-681页

作者： S. M. Sayedur Rahman Diponkar Paul md. masud rana City University Dhaka Bangladesh

An uninterruptible power supply (UPS) is a power conditioner that provides emergency power to a load when the supply power fails. In on-line UPS, the load is always connected to the inverter through the UPS static switch. Specialized expertise was required for collection, analysis, and dissemination of technical information relating to high quality uninterruptible power systems. Inherent in these responsibilities is the coordination of technical and contractual matters relating to the procurement and installation of uninterruptible power supply (UPS) systems which were required to support these facilities. The proposed circuit incorporates an AC/DC & DC & AC converter, which provided power factor correction and to assure feedback control. In our project when the AC main is available, the rectifier circuit will supply the power to the inverter as well as to the battery and battery will be charged. If the supply power fails suddenly, the battery will supply power to the inverter without any interruption and delay. In the constant current charging technique, a digital charger was designed and controlled through PIC12F675 microcontroller. In the realized system, The PIC16C73B was used as microcontroller. It was used to generate sinusoidal PWM (Pulse Width Modulation) signals that are connected to drive n-channel MOSFETs in inverter to assure feedback control and display units. The power circuit of the proposed UPS system was presented and analyzed. Circuit models were derived and a UPS digital control system using a digital signal processing (DSP) with microcontroller has been developed. The uninterruptible Power Supplies (UPS) are widely used by power supply during interruption of regular power supply due to load shedding, power failure, power fluctuations including telecommunication systems, medical systems, industrial control systems etc.

关键词： PWM Inverter MTBF ADC PIC

Design of a Multiband Patch Antenna for 5G Communication Systems

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Open Journal of Antennas and Propagation 2018年第1期6卷 1-14页

作者： Atik Mahabub md. Mostafizur Rahman md. Al-Amin md. Sayedur Rahman md. masud rana Department of Electronics and Communication Engineering KUET Khulna Bangladesh Department of Electrical and Electronic Engineering KUET Khulna Bangladesh

Currently, communication system requires multiband small antennas for 5G mobile applications. Driven this motivation, this paper proposes a multiband patch antenna for Wi-Fi, WiMAX and 5G applications. The proposed antenna can effectively operate at 2.4 GHz as Wi-Fi, 7.8 GHz as WiMAX and 33.5 GHz as 5G communication purposes. The proposed antenna arrays have given directional radiation patterns, very small voltage standing wave ratio, high gain (VSWR) and directivity for each aforementioned systems operating frequency. This antenna is made for multiband purpose which can be effective for not only Wi-Fi and WiMAX but also 5G applications.

关键词： 5G Communication Systems Multiband Patch Antenna Wi-Fi and WiMAX Systems

Adsorption of Anionic and Cationic Dyes from Textile Effluents by Activated Carbon Prepared from Sawdust and Fish Scale

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Advances in Chemical Engineering and Science 2023年第3期13卷 189-202页

作者： Rumana A. Jahan md. Mahedi Hassan Ashequl Alam rana Mohammad Mainul Karim Centre for Advanced Research in Sciences University of Dhaka Dhaka Bangladesh Department of Applied Chemistry and Chemical Engineering University of Dhaka Dhaka Bangladesh

In Bangladesh, there are thousands of textile-dying industries spread across the country’s many regions, the majority of which involve knitting and dying. The dyeing industry uses an enormous quantity of water, as well as colors and chemicals. After the dying process has been completed, they also release a significant amount of wastewater. Cotton, wool, and polyester fiber are typically dyed with textile dyes such as reactive, acid, and disperse dyes. These dyes are utilized most frequently in the respective sectors. The dyes’ colorants are extremely poisonous and dangerous to all forms of life, including aquatic life and living things. The present work has been intended to investigate whether or not it is practicable to remove commonly used textile dyes simultaneously from an aqueous dye solution using an adsorption technique that makes use of a variety of different adsorbents. This study focuses on the removal of color from two distinct types of dyes—Methylene Blue and Reactive Blue-250 which are cationic and anionic in nature respectively, using two different types of activated carbon adsorbents prepared from sawdust and fish scale. Dye removal capacity was tested as a function of contact time, the dosage of the adsorbent, pH during the treatment process, temperature and initial concentration of dye. The applicability of the Langmuir and Freundlich adsorption isotherms in describing experimental data was investigated. The micro and mesoporous activated carbon prepared from sawdust and fish scale identified by Scanning Electron Microscopy (SEM) images indicated that such adsorbents with a large surface area have more dye adsorption potential whereas the variation in dye adsorption occurs due to variation in surface area. From the overall experimental data, maximum removal of 95.39% and 87.92% was found for Methylene Blue and Reactive Blue-250 respectively by sawdust, and 90.64% removal of Methylene Blue by using fish scale.

关键词： Textile Wastewater Ionic Dyes Removal Activated Carbon Adsorbent

Data Prediction in Distributed Sensor Networks Using Adam Bashforth Moulton Method

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Journal of Sensor Technology 2018年第2期8卷 48-57页

作者： md Monirul Islam Zabir Al Nazi A. B. M. Aowlad Hossain md.masud rana Department of Electronics and Communication Engineering Khulna University of Engineering and Technology Khulna Bangladesh

Information collection from remote location is very important for several tasks such as temperate monitoring, air quality investigation, and wartime surveillance. Wireless sensor network is the first choice to complete these types of tasks. Basically, information prediction scheme is an important feature in any sensor nodes. The efficiency of the sensor network can be improved to large extent with a suitable information prediction scheme. Previously, there were several efforts to resolve this problem, but their accuracy is decreased as the prediction threshold reduces to a small value. Our proposed Adams-Bashforth-Moulton algorithm to overcome this drawback was compared with the Milne Simpson scheme. The proposed algorithm is simulated on distributed sensor nodes where information is gathered from the Intel Berkeley Research Laboratory. To maximize the power saving in wireless sensor network, our adopted method achieves the accuracy of 60.28 and 59.2238 for prediction threshold of 0.01 for Milne Simpson and Adams-Bashforth-Moulton algorithms, respectively.

关键词： Adams-Bashforth-Moulton Method Energy Saving Milne-Simpson Method Wireless Sensor Networks

Internal Jugular Vein Graft after Inadvertent Severing of the Internal Carotid Artery during Carotid Endarterectomy and an Urgent Re-Exploration for Immediate Post-Operative Wound Site Bleeding: A Case Report

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Open Journal of Modern Neurosurgery 2023年第2期13卷 94-104页

作者： md Shahid Hasan Khan md Shahidur Rahman Sikdar Muhammad Robiul Hoque Hojaifa Ahmad Aminur Rahman md Ahsan Arif md Atique Rahman Tanbir Siddique md Motashimul Hasan md Sumon rana md Shafiqul Islam Department of Neurosurgery Dhaka Medical College Hospital Dhaka Bangladesh Department of Neurosurgery Dhaka Medical College Dhaka Bangladesh

Carotid endarterectomy is a well-established treatment for preventing stroke in selected patients. Although there is debate over whether patch angioplasty or primary closure should be used to reconstruct the bifurcation after carotid endarterectomy, there is growing evidence in the literature in favor of patch angioplasty. When compared to primary closure, patch angioplasty during conventional carotid endarterectomy is suggested to lower the incidence of restenosis and recurrent ipsilateral stroke. Various materials have been used as a patch in this procedure, including the saphenous vein, synthetic patches, or less frequently, an internal jugular vein patch where extensive narrowing of the internal carotid artery is evident. In our case, we used an internal jugular vein graft after inadvertent severing the internal carotid artery (ICA) during carotid endarterectomy after the failure of reconstruction with a saphenous vein patch. We also encountered immediate postoperative reactionary hemorrhage following anesthetic reversal, necessitating an urgent re-exploration. The purpose of this case report is neither an attempt to suggest all patients need angioplasty nor to state that an internal jugular vein patch or graft is superior to synthetic material or saphenous veins;rather, it is an attempt to emphasize a potentially effective rescue way to reconstruct inadvertent extensive vascular injury during carotid endarterectomy.

关键词： Carotid Endarterectomy Internal Jugular Vein Graft Venous Patch Reactionary Hemorrhage

Wireless Head Gesture Controlled Robotic Wheel Chair for Physically Disable Persons

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Journal of Sensor Technology 2020年第4期10卷 47-59页

作者： Shadman Mahmood Khan Pathan Wasif Ahmed md. masud rana md. Shahjalal Tasin Faisul Islam Anika Sultana Department of Mechatronics Rajshahi University of Engineering & Technology Rajshahi Bangladesh Department of Electrical & Electronic Engineering Rajshahi University of Engineering & Technology Rajshahi Bangladesh Department of EEE Rajshahi University of Engineering & Technology Rajshahi Bangladesh

A robotic wheelchair is assumed to be capable of doing tasks like navigation, obstacle detection, etc. using sensors and intelligence. The initial part of the work was development of a cap controlled wheelchair to test and verify the gesture operation. Following that, a real time operating wheelchair was developed consisting of mode changing option between joystick control mode and head gesture control mode as per as the user’s requirement. The wheelchair consists of MPU6050 sensor, joystick module, RF module, battery, dc motor, toggle switch and Arduino. The movement of the head is detected by MPU6050 and the signal is transmitted to the microcontroller. Then the signal is processed by controller and motion of wheelchair is enabled for navigation. The wheelchair was capable of moving left, right, forward and backward direction. The speed of the wheelchair was 4.8 km/h when tested. Design objective of the wheelchair included cost effectiveness without compromising safety, flexibility and mobility for the users.

关键词： Head Gesture Wheel Chair Arduino Motor Driver Joystick Module

Susceptibility of microorganism to selected medicinal plants in Bangladesh

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Asian Pacific Journal of Tropical Biomedicine 2014年第11期4卷 911-917页

作者： S.M.masud rana md.Mustahsan Billah Mohammad Salim Hossain A.K.M.Saifuddin S.K.M.Azizul Islam Sujan Banik Zannatul Nairn Golam Sarwar Raju Department of Pharmacy Noakhali Science and Technology UniversitySonapurNoakhali-3814Bangladesh Department of Physiology Biochemistry and PharmacologyChittagong Veterinary and Animal Sciences UniversityChittagongBangladesh Department of Pharmacy Atish Dipankar University of Science and TechnologyBananiDhakaBangladesh

Objective:To analyze in-vitro antimicrobial activities of some ethno-pharmacologically significant medicinal plants(methanol extract) against the pathogenic microorganisms(Escherichia coli,Salmonella spp..Bacillus *** *** niger and Candida albicans).Methods:The disc diffusion method was applied for antibacterial test and the poisoned food technique was applied for antifungal ***:The methanol extract of Terminalia chebula(bark),Fhyllanthus acidus(fruits).Sarcochlamys pulcherrima(leaves) and Abelmoschus esculcntus(fruits) had significant in vitro antibacterial activity angainst the entire test samples in comparison to standard drug *** of the plant extracts showed low activity against Gram negative bacteria while potential activity against Gram positive *** antifungal activities of methanol extracts of these plants and standard drug griseofulvin were determined against two pathogenicfungi,and Polygonum Iapathifolium(leaves) and Cinnamomum tamala(leaves) showed maximum activity,while Erioglossum rubiginosum(leaves) showed no antifungal ***:Further chemical and pharmacological investigations are required to identify and isolate chemical constituents responsible for these potential bioactivities and thus to determine their full spectrum of efficacy.

关键词： Susceptibility Zone of inhibition Percentage of inhibition Antibacterial activity Antifungal activity

Use of Gramoxone 20SL (Paraquat) Prior to Land Preparation in Controlling Aquatic Weeds in Wetland Areas of Bangladesh

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American Journal of Plant Sciences 2014年第3期5卷 358-363页

作者： md. masud rana md.Abdullah Al Mamun Mohammad Habibullah md. Imran Ullah Sarkar md. Abdul Jalil Mridha Agronomy Division Bangladesh Rice Research Institute Gazipur Bangladesh Product Evaluation & Assessment Syngenta Bangladesh Limited Dhaka Bangladesh Soil Science Division Bangladesh Rice Research Institute Gazipur Bangladesh

Emergent aquatic weeds present in the monocropped fresh water wetland area of Bangladesh create a hazard in land preparation by developing dense stands. A field experiment was conducted at the farmers’ field of two villages namely Mahilara and Kashemabad under Gournadi Upazila of Barisal district, Bangladesh during October 2012 to evaluate the efficacy of Gramoxone 20SL (Paraquat) in controlling emergent aquatic weeds and to find out an appropriate dose of this herbicide. Three doses of Gramoxone 20SL at 1.96 l·ha-1, 2.00 l·ha-1 and 2.04 l·ha-1 were tried with an untreated control. All treatments were laid out in a randomized complete block design and replicated thrice. There were 8 different emergent weed species infesting the field among which the most dominant weed species were Eichhornia crassipes, Pistia stratiotes, Enhydra fluctuans, Monochoria vaginalis, Echinochloa crus-galli. The results revealed that, weed control efficiency was significantly affected by different herbicidal treatments. The treatments, Gramoxone 20SL at 2.00 l·ha-1 and 2.04 l·ha-1 were controlled in all the emergent aquatic weeds more than 85% infesting both the sites. Application of non-selective herbicide Gramoxone 20SL at 2.00 l·ha-1 prior to land preparation was most effective to suppress weed dry masses in both the site resulting reduced land preparation cost up to 78.93% as compared to manual weed control.

关键词： Aquatic Weeds Gramoxone 20SL SDR Weed Control Efficiency