Browsing by Author "Rahman, Md. Mahbubur"

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A Comparative Analysis of Medicinal Plants used by Several Tribes of Chittagong Hill Tracts Region, Bangladesh to Treat Helminthic Infections
(The American-Eurasian Network for Scientific Information (AENSI), 2010) Rahmatullah, Mohammed; Jahan, Rownak; Hossan, Md. Shahadat; Seraj, Syeda; Rahman, Md. Mahbubur; Chowdhury, Anita Rani; Miajee, Z.U.M. Emdad Ullah; Nasrin, Dilruba; Khatun, Zubaida; Jahan, Farhana Israt; Khatun, Afsana
Chittagong Hill Tracts region is largely a forested region in the south-eastern part of Bangladesh. A number of tribes are settled in this region. Helminthiasis (infestation of intestine with parasitic worms) is fairly prevalent within the tribes because of poor sanitary conditions. The tribal people visit their own traditional medicinal practitioners to treat helminthic infections, more so because modern medicinal facilities are absent within the forested areas. Tribal traditional medicinal practitioners rely on medicinal plants for treatment of helminthiasis. The objective of the present survey was to conduct a survey among the Chak, Chakma, Marma, Murong, Rakhain and Tonchonga tribal traditional medicinal practitioners to learn more about medicinal plants used by them for treatment of helminthic infections. Helminthic infections are prevalent worldwide and medicinal plants can be a potential source for discovery of more efficacious drugs. A total of 10 plant species distributed into 8 families were observed to be used by the surveyed tribes to treat helminthiasis. The number of medicinal plants used by the Chak, Chakma, Marma, Murong, Rakhain and Tonchonga tribes to treat helminthic infections were respectively, 1, 4, 1, 3, 3, and 3. Ananas comosus (L.) Merr. was used in common by the Chak, Chakma, Rakhain, and Tonchonga tribes. Cassia alata L. was used in common by the Chakma and Murong tribes. Erythrina variegata L. was used in common by the Chakma, Marma, and Murong tribes. The various plant parts used included leaves, roots, barks, flowers, and fruits. The percent use of these plant parts were, respectively, 52.6, 15.8, 21.1, 5.3 and 5.3%. Mostly, a single plant or plant part was used for treatment of helminthiasis, although use of combinations of plant parts was also observed in three instances. There was only one instance where a combination of plant species was used. The Chakma tribe used a combination of leaves of Ananas comosus along with roots of Areca catechu L. and bark of Erythrina variegata for treatment of helminthiasis. The medicinal plants used by the various tribes of Chittagong Hill Tracts present considerable potential for scientific studies towards discovery of more effective medicines to treat helminthiasis, which can be caused by a variety of parasitic worms and is endemic throughout the different countries of the world. Full Text Link: http://scinet.dost.gov.ph/union/Downloads/105-111_224634.pdf
A Comparative Analysis of Medicinal Plants used by Three Tribes of Chittagong Hill Tracts Region, Bangladesh to Treat Leukorrhea
(The American-Eurasian Network for Scientific Information (AENSI), 2010) Rahmatullah, Mohammed; Jahan, Rownak; Hossan, Md. Shahadat; Seraj, Syeda; Rahman, Md. Mahbubur; Chowdhury, Anita Rani; Begum, Rahima; Nasrin, Dilruba; Khatun, Zubaida; Hossain, Mohammad Shahadat; Khatun, Afsana; Jahan, Farhana Israt
Leukorrhea is the flow of whitish, yellowish or greenish discharge from the vagina of a female, which can happen under normal conditions as well as bacterial or fungal infections. Such discharges may originate from the vagina, ovaries, fallopian tubes, or, most commonly, the cervix. In our ongoing ethnomedicinal surveys among the various tribes and regions of Bangladesh, it was observed that leukorrhea due to infections were common among the tribal women as evidenced by the number of plants used by the tribal medicinal practitioners to treat this infective condition. The objective of the present survey was to learn more about the medicinal plants used for treatment of leukorrhea by the tribal medicinal practitioners of the Chakma, Murong and Tonchonga tribes. All three tribes reside in the southeastern forested region of Bangladesh known as the Chittagong Hill Tracts. Informed consent was obtained from the tribal medicinal practitioners and interviews were conducted with the help of a semi-structured questionnaire and the guided field-walk method. It was observed that the tribal medicinal practitioners of the Chakma, Murong, and Tonchonga tribes used 13 plant species distributed into 12 families for treatment of leukorrhea. Roots constituted the major plant part used (53.3%), followed by leaves (20.0%), bark (13.3%), and whole plant and stem (6.7% each). The Kavirajes did not distinguish whether the leukorrhea originated from bacterial or fungal infections of the vagina or was due to other complications of the ovary, fallopian tube or cervix. In general, any sign of especially whitish discharge from the vagina of females was treated as leukorrhea and medications prescribed accordingly. Since the tribal population in their densely forested abodes lack access to modern medicinal facilities, the medicinal plants can form a primary mode of health-care for treatment of this occasionally infective medical condition in females.
A Randomized Survey of Medicinal plants used by Folk Medicinal Practitioners in Daudkandi sub-district of Comilla district, Bangladesh
(The American-Eurasian Network for Scientific Information (AENSI), 2010) Rahmatullah, Mohammed; Momen, Md. Abdul; Rahman, Md. Mahbubur; Nasrin, Dilruba; Hossain, Md. Shahadat; Khatun, Zubaida; Jahan, Farhana Israt; Khatun, Afsana; Jahan, Rownak
Folk medicinal practitioners (Kavirajes) are possibly the most ancient practitioners of traditional medicine in Bangladesh and in general are the primary health-care providers to a majority of the rural population and a substantial segment of the urban population in the country. The major characteristic that separates the folk medicinal practitioners from other systems of existing medicinal practices is their almost exclusive use of simple preparations of medicinal plants for treatment of various ailments. Since the population of Bangladesh is primarily rural, village Kavirajes form the major unit from whom ethnomedicinal data can be obtained. The objective of the present study was to conduct a randomized ethnomedicinal survey among the Kavirajes of four villages, Kalakandi, Gorashal, Kadamtoli, and Gunjar, all villages being situated in Daudkandi sub-district of Comilla district in Bangladesh. Informed consent was obtained from the Kavirajes and surveys were carried out with the help of a semi-structured questionnaire and the guided field-walk method, where the Kavirajes took the interviewers to places from where they collected their medicinal plants, pointed out the plants and described their uses. All plant specimens were collected and identified at the Bangladesh National Herbarium. It was observed that the Kavirajes of the four villages surveyed used 44 plant species distributed into 32 families. The Lamiaceae family contributed 4 plants, followed by the Leguminosae, Rutaceae, and Solanaceae families with 3 plants each. Leaves constituted the major plant part used (45.3%), followed by roots (13.2%), and whole plants, fruits, and seeds (7.5% each). The various ailments treated included respiratory tract problems, gastrointestinal disorders, sexual problems, fever, cardiovascular disorders, mental disease, diabetes, loss of hair, vomiting, menstrual problems, skin disorders, hepatic disorders, piles, leprosy, calcium deficiency, dental diseases, cracked foot, bleeding, insect bites, mumps, rabies, chicken pox, body ache, and bone fracture. Cumulatively, the plants obtained in the present survey present considerable potential for further scientific research towards discovery of lead compounds and more efficacious drugs.
A Randomized Survey of Medicinal Plants used by Folk Medicinal Practitioners in Ten Districts of Bangladesh to Treat Leprosy
(GALE, 2010-05) Rahmatullah, Mohammed; Jahan, Rownak; Azad, A. K.; Seraj, Syeda; Rahman, Md. Mahbubur; Chowdhury, Anita Rani; Begum, Rahima; Nasrin, Dilruba; Khatun, Zubaida; Hossain, Mohammad Shahadat; Khatun, Afsana; Miajee, Z.U.M. Emdad Ullah; Jahan, Farhana Israt
Leprosy is a chronic disease caused by the microorganisms Mycobacterium leprae and Mycobacterium lepromatosis. It is primarily a granulomatous disease of the peripheral nerves and mucosa of the upper respiratory tract. The pauci-bacillary form of leprosy is treated with the drugs, rifampicin and Dapsone (diamino-diphenyl sulfone), while the multi-bacillary form of the disease is treated with the drugs rifampicin, clofazimine, and Dapsone. Bangladesh is one of the five countries who contribute to 82% of the sufferers from this disease world-wide. The disease is prevalent especially among the rural and urban poor, who despite provision of modern treatment often visit folk medicinal practitioners, who utilize medicinal plants for treatment of leprosy. Since the above drugs has been reported to have a number of adverse side-effects, it was of interest to document the medicinal plants used to treat leprosy in Bangladesh for such plants can prove to be valuable sources of drugs with less side-effects. Randomized ethnomedicinal surveys were therefore carried out in ten districts of Bangladesh to learn more about medicinal plants used by folk medicinal practitioners. Informed consent was obtained from the practitioners prior to interviews, which were conducted with the help of a semi-structured questionnaire and the guided field-walk method. The names of 16 plants were obtained, the plants being distributed into 11 families. The Combretaceae family provided the highest number of three plants followed by the Apocynaceae and Fabaceae families with 2 plants each. The various plant parts used to treat leprosy included whole plant, leaves, barks, roots, and seeds. The plants present considerable potential for discovery of novel compounds with less side-effect for treatment of leprosy and can, at least in Bangladesh, become a source of affordable and more easily available drugs.
A review on supercapacitor & its application
(IUT, EEE, 2016-11-20) Rahman, Md. Mahbubur; Al Joha, Md. Abdullah; Ahsan, Shadman
Capacitors are commonly used in electronic resonance circuits; however, capacitors have not been used for storing large amounts of electrical energy in electrical circuits. Also they are not known to be long lasting. Thus appears the need of supercapacitor with variety of electrodes, offering high power density, fast charging & elongated life-cycle. Highly conducting and porous carbon nanotube (CNT) networks are popular as the sole electron conducting material in supercapacitors. The high conductivity of CNT networks and the high surface area allow the replacement of both the metallic current collector and the active material that forms one side of the electrochemical double layer. The combination of both functions in one single layer leads to lightweight charge storage devices that can be manufactured using simple and cheap room temperature methods. In case of solid-state supercapacitor, device fabrication is done by a simple vacuum thermal evaporation method, which allows not only a multilayer stacking structure to further enhance the capacitance, but also permits the supercapacitor to be easily incorporated with other electronic devices, showing interesting characteristics for both fundamental study and practical applications. supercapacitors are being used to increase the efficiency of hybrid electric vehicles in several ways. Aging of a capacitor is a topic to be concerned about. The voltage difference in cells and temperature tend to shorten the life span. Methods are being developed to tackle this problem. Until recently, supercapacitors were relegated to fairly mundane applications such as memory protection and internal battery backup, but in the last few years the application space has broadened significantly into hybrid vehicles, smartphones, and energy harvesting. New technologies on the horizon promise to bring supercapacitors into full competition with rechargeable batteries
A survey of medicinal plants used by folk medicinal practitioners for treatment of gastrointestinal disorders in randomly selected areas of four districts of Bangladesh
(The American-Eurasian Network for Scientific Information (AENSI), 2010) Rahmatullah, Mohammed; Jahan, Rownak; Rahman, Md. Mahbubur; Seraj, Syeda; Nasrin, Dilruba; Khatun, Zubaida; Chowdhury, Anita Rani; Azad, A.K.; Khatun, Afsana; Begum, Rahima; Jahan, Farhana Israt
Bangladesh is a small developing country with the majority of population living in over 86,000 villages spread around the country. A substantial portion of the urban population lives in slum areas. Both rural population as well as the urban slum population resides under conditions where proper sanitation conditions are lacking and the drinking water quality is usually poor. As a result various types of gastrointestinal disorders are prevalent throughout Bangladesh. A large number of the rural and urban slum people obtain treatment for various gastrointestinal disorders from folk medicinal practitioners (Kavirajes), who rely on simple preparations of medicinal plants for treatment. The objective of the present study was to conduct a survey among the Kavirajes of various randomly selected areas in four districts, namely, Rajshahi, Jessore, Tangail, and Dinajpur in Bangladesh. The districts are located, respectively, in the northern, southern, central, and northern part of the country. Informed consent was obtained from the Kavirajes prior to the survey. Interviews were conducted with the help of a semi-structured questionnaire and the guided field-walk method, where the Kavirajes took the interviewers to spots from where they collected their medicinal plants, pointed out the plants, and gave their local names and uses. All plant specimens were collected and dried in the field and later brought to Bangladesh National Herbarium, Dhaka for complete identification. Considerable variation was observed in the family and species of medicinal plants used for treatment of gastrointestinal disorders by the Kavirajes of the four districts surveyed. The Kavirajes of two surveyed villages of Rajshahi district used 9 plants distributed into 8 families; the Kavirajes of four surveyed villages of Jessore district used 5 plants distributed into 5 families; the Kavirajes of a small town surveyed in Tangail district used 7 plants distributed into 6 families; and the Kavirajes of two villages in Dinajpur district used 25 plants distributed into 18 families. The use of whole plant or plant parts also differed considerably between the Kavirajes of the four districts. The Kavirajes of Rajshahi district used the leaves, roots, fruits, and seeds, while the Kavirajes of Jessore district used only the leaves, stems, and barks of plants. The Kavirajes of Tangail district used mainly the stems followed by roots, while the Kavirajes of Dinajpur district used mostly the leaves of medicinal plants followed by fruits. The survey highlights the considerable differences in medicinal plant usage by Kavirajes of different areas of Bangladesh. At the same time, the survey points out the diversity of plant species present in the country form treatment of gastrointestinal disorders, which comprises of a number of ailments prevalent worldwide and suggests that considerable potential exists for modern scientific studies to be carried out on the medicinal plant species in the quest for better drugs.
Analyzing the Performance of Deep Learning Models for Detecting Hate Speech on Social Media Platforms
(Research and Development Wing, MIST, 2024-12) Islam Arif, Md Ariful; Rahman, Md. Mahbubur; Rabiul Alam, Md. Golam; Akhtaruzzaman, M.
Currently social media and online platforms have become a major source of cyberbullying and hate speech. It is currently affecting people and communities in harmful ways. Hate speech on social media is rising in Bangladesh and it is creating a need for effective tools to prevent and detect these incidents. This study introduces a deep learning model to mitigate this issue of identifying hate speech in text using three types of word embedding methods: Word2Vec, FastText, and BERT. The text data was labeled to mark hate speech and non-hate speech content. After that, these texts are preprocessed by removing punctuation and symbols to help improve model accuracy. Five deep learning models Bi-GRU-LSTM-CNN, Bi-LSTM, CNN, LSTM, and XGBoost were trained to classify the text as hate speech or non-hate speech. The study found that the LSTM model accomplished the highest accuracy at 95.66% with the Word2Vec embedding method, while CNN reached 87.70% with FastText embeddings. Word2Vec is effective for capturing word meanings in general text classification. FastText works well with rare words and languages that have complex word forms. These findings help advance effective hate speech detection techniques. It could promote more respectful and inclusive interactions on social media. This proposed deep-learning model can help stop cyberbullying and hate speech on social media.
Bangla Document Classification using Character Level Deep Learning
(IEEE, 2020-10) Rahman, Md. Mahbubur; Sadik, Rifat; Biswas, Al Amin
Last few decades, the availability and accessibility of the Bangla document and its content have rapidly increased due to the rapid technological advancement. Intense research needs to be performed on various Bangla documents due to the diversity of the language and associated sentiment. Document classification is one of the fundamental problems of Natural Language Processing. To handle miss-classification and convenient indexing and searching of Bangla documents on the web, researchers nowadays exploring different fields of computer science to classify Bangla documents. In this paper, Deep Learning based approaches are implemented to classify Bangla text documents. Convolutional Neural Network (CNN) and Long Short Term Memory (LSTM) is used here for the classification task. Here we have implemented an advanced technique that encoded the documents at their character level. Documents from three different data sources are used to validate and test of the working models. The highest classification accuracy is 95.42% that is achieved on the Prothom Alo data set using LSTM. Furthermore, we presented a comparison between two models and explained how well the classification task can be carried out using our character level approach with higher accuracy.
Bangla News Classification Using Graph Convolutional Networks
(2021 International Conference on Computer Communication and Informatics (ICCCI), IEEE, 2021-04-21) Rahman, Md. Mahbubur; Khan, Md. Akib Zabed; Biswas, Al Amin
Online Bangla news has rapidly increased in the era of the information age. Each news site has its different categorization for grouping their news. The Layout and categorization of the online Bangla news articles cannot perpetually meet the individual's needs due to the heterogeneity. So, overcoming this issue and classifying the online Bangla news articles according to the preference of the user is an arduous task. So, it is essential to provide state-of-the-art solutions as well as the best way to solve this problem. The paper aims to build an automated system to classify the Bangla news contents and also find out the state-of-the-art solutions for the small size dataset. It is known that most of the machine learning models need huge amounts of data for the proper training and testing of the models. But due to the scarcity of the dataset, it is not always possible to provide the state-of-the-art solutions. But, in this research work, we have found that Text-GCN performed better than the BiLSTM, GRU-LSTM, LSTM, Char-CNN, and BERT to classify the online Bangla news in spite of the small size of the dataset. The obtained experimental result shows the efficiency of the Text-GCN over the other models in terms of accuracy, precision recall, and F1-score.
Chevron Bangladesh
(BRAC University, 8/22/2013) Rahman, Md. Mahbubur; Faruqui, Mahtab
Chevron is one of the world’s leading integrated energy companies. Chevron’s success is driven by its people and their commitment to get results the right way — by operating responsibly, executing with excellence, applying innovative technologies and capturing new opportunities for profitable growth. Chevron is involved in virtually every facet of the energy industry. Chevron explore for, produce and transport crude oil and natural gas; refine, market and distribute transportation fuels and lubricants; manufacture and sell petrochemical products; generate power and produce geothermal energy; provide renewable energy and energy efficiency solutions. Chevron operates in more than 180 countries. It has 3 major businesses which are Upstream, Gas and Midstream & Downstream. Upstream is responsible for the exploration and production of oil and natural gas worldwide. Gas and Midstream (CGM) creates enterprise value through crude, natural gas and product trading, shipping, pipelines and power generation. Downstream & Chemicals (DS&C) refines and market fuels, lubricants and chemical additives. Mainly Downstream & Chemicals manages the refining, sales and marketing of fuels and lubricants to retail, commercial and industrial customers through its Manufacturing, Products, Lubricants and Oronite business units. Chevron Bangldesh not only brought a dynamic change in Bangladesh in case of Gas production but also brought the 134 years experience of producing energy, oil, gas worldwide. Currently Chevron is producing nearly 1150 MMscfd . They produce nearly 50% gas of total gas production of Bangladesh. . Chevron Bangladesh operates on Jalalabad, Moulavi Bazar and Bibiyan Gas field. Chevron, having invested nearly a US$ 1 billion, is one of the largest foreign investors in the energy sector of Bangladesh and supplies 45% of the country’s gas needs. Chevron operates in Bangladesh on the basis of PSC (Production Sharing Contract) signed between PetroBangla.
Child Rearing practices of children with disabilities
(BRAC University, 7/10/2011) Rahman, Md. Mahbubur; Khanam, Dr. Wahida
Design and Development of Online Tourism in Bangladesh
(Daffodil International University, 2018-12) Bhowmik, Tanmoy; Mohanto, Debdash; Rahman, Md. Mahbubur
This project is based on tourism sector. This is a kind of web system which help the tourists find their wished for visiting places and places of circumstance as well. The goal of the system is mainly to help the tourism sector of local tourists and foreigner tourists. The site is guided to tours and travel management system and the aim was to pursue Tour and Travel packages. We provide the most suitably schematic as well as the customized travel packages to the customers. We payoff everything related to travelling services under one roofing. The tourists can use this site for different purposes like searching a location, nearby locations getting basic textual information, pictorial information of location which normally we could not find in default Google maps. The main problem is tourist cannot get a proper idea with some static information. The website covers all the areas needful for an including tourism. The main module in this project are login, tourist management, reviews, packages, booking bus tickets and online chatting system. After embodiment it would be hosted in a server. All facilities in a live website can’t be given in localhost but most of the ardor will work fine. To upload the website a web server with essential security is needed. After implementation of all function, the system is tested in different stages and it works successfully as a prototype.
Determination of Fibre Blend Ratio in Jute-Cotton Blended Roving and Yarn
(Daffodil International University, 2020-07) Dayan, Md. Anisur Rahman; Rahman, Md. Mahbubur; Habib, Md. Mahmudul; Kaysar, Mohammad Abdullah; Uddin, Md. Moslem
Jute and cotton fibres are most important natural fibres. Cotton is being blended with jute fibre to impart comforts, technical properties, flexibility for producing diversified products and cost reduction. As cotton and jute both are natural cellulosic fibres, determination of individual percentage ratios in their blending by chemical analysis is difficult. Presence of individual fibres have been identified by FTIR analysis as jute possesses aromatic ring group and cotton does not. Fibre fineness analysis is also helpful to ensure the existence of jute fibre in jute-cotton blended materials. Here, blending ratio of jute and cotton fibre has been determined by dyeing and weighing process. Physical identification of component fibres by absorbing a selective dye with respect to jute has been helpful to differentiate and separate the jute-cotton fibres. In this respect, basic dye is substantive to jute fibre and pure cotton fibre has very poor substantivity to that dye. Using this technique, Jute and cotton fibres have been identified and manually separated from their blended roving and yarn. Their percentage ratios have been determined by weighing the separated fibres. This experimental results reveals that the Jute/Cotton weight percentage of jute cotton blended yarn was found as 16.58/83.42 respectively whereas the initial feed ratio of these fibres in blow room was 30/70. This research will help the spinners of jute-cotton blended yarns to control their desired product requirements and quality.
EFFECT OF REPLACEMENT CONCENTRATE BY HYBRID Azadirachta indica (NEEM) LEAVES ON GROWTH PERFORMANCE, INVITRO DIGESTIBILITY, ANTHELMINTHIC PROPERTIES AND MEAT QUALITY OF INDIGENOUS SHEEP.
(Chattogram Veterinary & Animal Sciences University, Khulshi-Chattogram, 2022-06) Rahman, Md. Mahbubur
This study was conducted to evaluate the effect of feeding of different proportions of neem tree leaves with/without concentrate mixture on the feed intake, digestibility, body weight gain, carcass parameters, as natural anthelmintic and meat quality of sheep. Hybrid neem leaves were harvested from 1 to 3 years age trees. After collection of leaf the fresh samples were dried at sunlight and then grounded into powder using a laboratory grinder. After grinding the powder were kept in plastic bags for Laboratory analysis and further use as Animal feed in experimental diet. A total 12 indigenous sheep with initial body weight approximate 12kg were selected from a flock of 30 animals of the CVASU animal farm. The animals were quarantined for seven days to get them used to their new environment and to observe their health condition. At the end of the quarantine period, the sheep was randomly allocated into four dietary treatments in a Completely Randomized Design (CRD) with three replications, each containing three animals. Concentrate mixture was replaced with dry neem leaves (foliage) at 0, 50, 100 and 150g among remaining 300g of diet and four experimental treatment were as: T1, 300g concentrate mixture; T2, 250g concentrate mixture + 50g dry neem foliage; T3, 200g concentrate mixture + 100g dry neem foliage; T4,150g concentrate mixture +150g dry neem foliage. All animals were weighed before morning feeding at the start of the experiment and each week interval. Daily faecal samples (2 days / week) were collected from each animal in the morning and this was continued for 6 weeks for the McMaster faecal egg counting. At the end of the feeding trial after two months, two sheep were randomly selected from each treatment and were slaughtered for determination of carcass and meat quality and collection of rumen fluid for estimation of in- vitro digestibility of the dietary supplements. Dry matter percentage of neem foliage, leaf, stem were 34.79%, 32.42%, 37.87% respectively. It is observed that neem stem contents more dry matter than leaf and foliage. Neem leaf has more moisture content than foliage and stem. Leaf content more ash, CP than other part of plant whereas stem content more fiber than leaf and foliage. The average daily weight gain of sheep increased significantly with increased amount of dry neem leaf and significantly higher live weight and superior feed conversion efficiency were found sheep fed T3 and T2 diet compared to other diet. After 14 days of trial start mean nematode faecal egg counts (E.P.G) decreased rapidly in neem treated group compared to those fed control diet. The sheep ix fed dietary supplements using 50gm to 100gm dry neem foliage had significantly (P<0.05) higher hot carcass percentage and numerically higher dressing yield compare to those fed other diet. Significantly (P<0.05) lower cook loss and drip loss was obtained sheep fed 100 to 150g dry neem foliage used in dietary treatments that is T3 and T4. In conclusion, 30% (100g) neem leaf meal can be used in dietary supplements to increase performance, digestibility and meat quality of sheep and to reduce feed cost and increase of net return of sheep rearing
Enhancing learners' English language proficiency through service learning : an investigation on BRAC University perspective
(BRAC University, 2012) Rahman, Md. Mahbubur
Service Learning concept shows the positive impacts on the active engagement of English language teachers as well as learners in creating appropriate scope for making a learning community both inside and outside the classroom. The students are perfectly connected to community service with the direct use of their integrated language skills unlike the traditional classroom teaching. Considering that fact, learners are put in real life situations to experience language skills so that instead of learning English, the learners have the scope for language acquisition. With a view to ensuring that principle, BRAC University has incorporated Starboard activity, English Week observance etc. as parts of integration between two academic courses: English and Ethics. This paper shows the impacts of these service-learning activities in improving the skills of language learners through investigating as well as carrying a message: “Serve to Learn”. After gathering data, SPSS copyright version 14 computer packages and Microsoft Office Excel 2007 version have been used to assess them.
Enhancing the security of cloud computing: Genetic algorithm and QR code approach
(IEEE, 2018-01-15) Dey, Samrat Kumar; Uddin, Md. Raihan; Kabir, Kh. Mohaimenul; Rahman, Md. Mahbubur
Paradigms of Cloud computing are gaining prevalent acceptance due to the numerous benefits they provide. These comprise cost-effectiveness, time savings and effective deployment of computing resources. However, privacy and security issues are among the major hindrances holding back the widespread adoption of this novel technology. In this context, enhancing the security of cloud computing demands the highest priority based on the popular encryption method RSA, Genetic Algorithm (GA), and 3D Quick Response (QR) code using MAC address. This paper will show an approach of amplifying the security of cloud computing. Therefore, we are proposing advanced two-step security mechanism of cloud computing. Firstly, RSA is used to provide initial protection of the first stratum. RSA approaches message as input to the hash function and generated hash values is encrypted by using generated sender key. And the receiver will generate a hash code and decrypts the message using the sender's public key. Finally, The Genetic algorithms (GA) are generalized search algorithms based on the mechanics of natural genetics. GA maintains a population of individuals that represent the candidate solutions. After successful completion of Genesis, mutation and crossover GA will provide a framework to match the desired pattern. Moreover, a media access control address (MAC address) of a device is a distinctive identifier assigned to network interfaces for communications at the data link layer of a network segment. In this context, the MAC address is used to generate the 3D Quick response code for user verification. Through experiments, we affirm that the combination of GA and 3D QR Code approach with RSA for two-step security mechanism shows strong potential to heighten the security of Cloud Computing.
Exploring vibration isolation of a superelastic shape memory alloy cantilever beam
(Department of Mechanical Engineering (ME), 2022-09-07) Rahman, Md. Mahbubur; Ashiqur Rahman, Dr. Muhammad
Vibration of a superelastic Shape Memory Alloy (SMA)cantilever beam has been analyzed comprehensively considering end-shortening effect, geometric non-linearity and effect of material non-linearity (that is, the beam material has a non-linear stress-strain relation and Hook’s law cannot be applied)for different forcing frequency and damping ratio. Difference between vibration for two equivalent cross-sections (circular and equivalent rectangular) has also been analyzed. Soundness of the developed mathematical scheme and computer code has been amply demonstrated in the present study. The Euler-Bernoulli’s geometrically non-linear governing equation and equation of classical theory for beam are solved numerically to generate the load-deflection relations. From these load-deflection relations, the restoring forces are chosen as best fit non-linear curves. Then this best fit non-linear curves of restoring forces are inserted into the equation of vibration that converts the equation into non-linear form which is solved numerically by the Runge-Kutta (R-K) 4th order method of integration since exact solution is not possible. Material non-linearity issue is handled in terms of a mathematical model that has been developed to solve pure bending of a beam. It should be noted here that, SMA inherently has highly non-linear stress-strain curves in tension and compression. Thus, bending moment-curvature and reduced modulus-curvature relations are obtained for a superelastic SMA circular and equivalent rectangular beams. Results are used to predict effect of material non-linearity on the response of vibration of the beam. Some interesting results can be observed from this thesis that the amplitude of the undamped vibration considering end-shortening effect is not going to be infinite over time at resonance(β = ω/ω_n =1) which is predicted by classical theory. It is also found that increased damping greatly reduces the vibration amplitude for both the classical theory with and without end-shortening effect. As material non-linearity is taken into account some portion of the beam is found to experience stresses (different magnitude in tension and compression) beyond proportional limit. Effect of material non-linearity becomes prominent as vibration amplitude starts to become large. Moreover, the maximum deflection of the beam is found to be much larger when material non-linearity is considered in comparison to the case of linearly elastic beam material. The amplitude of the vibration considering material non-linearity and geometric non-linearity with end-shortening effect is largely lower than that predicted by classical theory when the damping is low. Increased damping greatly reduces the vibration. The amplitude of the undamped vibration for circular beam is slightly higher than that of equivalent rectangular beam at resonance (β = 1) considering material non-linearity with end-shortening effect. When the geometric non-linearity issue is incorporated to the material non-linearity with end-shortening effect the discrepancy between the vibrations is reduced. The isolation of the vibration begins when the speed ratio (β) exceeds 1.414 for classical theory with any amount of damping but it requires higher speed ratio to start the vibration isolation when end-shortening effect is included. A very interesting result is found that the speed ratio (β) varies with the damping ratio to isolate the vibration considering material non-linearity and geometric non-linearity with end-shortening effect. A higher damping ratio requires a smaller speed ratio to begin the isolation. Key words: Cantilever Beam, End-Shortening, Equivalent Cross-section, Vibration Isolation, Transmissibility.
Federated GAN based biomedical image augmentation and classification for Alzheimer’s disease
(BRAC University, 2022-09) Roy, Aditya; Rahman, Md. Mahbubur; Ahmed, Shafi; Rabiul Alam, Md. Golam
Federated Learning (FL) is a distributed machine learning approach that can de velop a global or customized model from scattered datasets on edge devices using federated datasets. ‘Federated GAN Based Biomedical Image Augmentation and Classification for Alzheimer’s Disease’ will focus on augmenting the medical images using Federated Generative Adversarial Network. Due to patient-doctor confiden tiality, the scarcity of data in the medical sector is a massive hindrance to the advancement of machine learning models in this sector. Our study aims to augment the existing medical data, in this case, magnetic resonance imaging(MRI) images of the brain, and test that augmented dataset on existing classification models to eval uate our generated MRI images’ quality. Generative Adversarial Networks (GANs) have been utilized in order to synthesize realistic and varied Alzheimer’s disease affected MRI images in order to cover the data shortage in the actual medical image distribution and identify Alzheimer’s disease using Federated Learning. We expect our proposed model to successfully augment the medical images and be over 90% accurate at detecting the medical condition.
Fiber Types and Fabric Structures Influence on Weft Knitted Fabrics
(Daffodil International University, 2022-06-20) Hoque, Md. Saiful; Hossain, Md. Jakir; Rahman, Md. Mahbubur; Rashid, Md. Mizanur
The physical properties of weft knitted fabrics can be modified according to the fabric structure and the raw material used to manufacture the final fabric. This research demonstrates the influence of fiber types and fabric structure on some specific physical properties such as bursting strength, wicking behavior, pilling effect, and abrasion resistance of weft knitted fabrics. For this purpose, in this research study, one natural fiber cotton, one regenerated fiber viscose, and one synthetic fiber polyester were used. At the same time, to avoid any conflicts of the other fabric production factors, the number of feeders, machine diameter, needle gauge, stitch length was kept constant during the production of the weft-knitted fabrics. Moreover, three different structures of single jersey fabric like plain single jersey, single lacoste, and double lacoste were used to produce nine single jerseys of weft knitted fabric, while in each knit structure, three fabrics were produced using 100% cotton, 100% viscose, and 100% polyester fiber. Statistical analysis has been performed along with factorial analysis of variance (ANOVA) followed by simple main effect and simple comparison analysis. The finding illustrates that both fiber types and fabric structure regulate the physical properties of weft knitted fabrics. The polyester fiber seems to possess excellent mechanical properties such as bursting strength, abrasion, and pilling resistance without any influence of fabric structures studied in this research. However, both the fiber types and fabric structure combinedly influence the wicking of weft knitted fabrics. Additionally, it has been assumed that the influence of fiber types and fabric structure on strength, pilling, abrasion-resistant, and wicking properties of fabrics also combined with the areal density and extensibility of weft knitted fabrics.
Gender equality in Rokeya's writing
(BRAC University, 2013-04) Rahman, Md. Mahbubur; Azim, Firdous
This thesis looks into the notion of gender equality and its reflection in Rokeya Sakhawat Hossain’s writing. It analyzes the meaning and importance of gender equality, types, causes and consequences of gender inequality and the recommendations of Begum Rokeya for eradication of the gender based inequalities from the society. In this regard, I have reviewed eight texts from Rokeya’s writing. These are Padmaraag (a novel), Sultana’s Dream (a short story), Abarodh Bashini (a collection of true cases of seclusion), Stree Jatir Abanati (an essay), Ardhangi (an essay), Burqa (an essay), Sugrihini (an essay) and Shristee Tattha (a short story). I have observed that Rokeya’s views on gender equality are more or less similar to the views expressed by modern social scientists. This thesis notes that Rokeya delineated the importance of gender equality from political and development perspectives. This thesis further notes that Rokeya had explained four types of gender inequality: denial of equal social status, denial of human rights of women, denial of property rights of women and confinement. This thesis shows that Rokeya chalked out six causes of gender inequality: lack of women’s education, lack of women’s interest in career, psycho-social complexities in female-female relationships, lack of opportunities, exaggeration in practice of seclusion and male perceptions towards women’s education. This thesis also encapsulates the consequences of gender inequality, i.e., low participation of women in the field of education that ultimately undermines progress/development, as sketched by Rokeya. Finally, this thesis identifies five strategies for eradication of gender inequality as advised by Rokeya: spreading women’s education; strengthening community networks; empowering women; rectifying unnatural practice of seclusion; and getting men involved and changing their perception towards women’s education.