Browsing by Author "Rafiqul Islam, Md."

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Chemical and microbiological studies on some medicinal plants
(Department of Chemistry , BUET, 2000-09) Rafiqul Islam, Md.; Enamul Huq, Dr.
Antibacterial activity of ten locally available medicinal plants, Terminalia ar}una (Arjun), Rauvo/fia serpentina (Sharpagandha), Holarhena antidysenterica .(Kurchi), Aegle marmelos (Bel), HeIiotropium indicum (Hatisur), Helicteres isora (At mora), Syzygium cumini (Kalojam), Polygonum hydropiper (Biskatali), Spondias pinnata (Amra), Swertia chirata (Chirata) were studied against ten gram negative & one garm positive bacteria. Methanol extract of the seeds of Ho/arhena antidysenterica was found to be active against S.aureus; Methanol extract of the bark of Terminalia arjuna was active against Shigella dysenteriae, Shigella jIexneri, Shigella sonnei, Escherichia coli and S.aureus; and Methanol extract of the roots of Rauvo/fia serpentina was active against s.aureus. Extracts of the other plants showed no antibacterial activity. Fractionation of Methanol extracts were carried out by solvent extraction and lor column chromatographic techniques. Antibacterial activity tests of different fractions were carried out against the same test organisms. Ethyl acetate fraction of methanol extract of H.antidysenterica was found to be active against Saureus; Pet. ether-Ethyl acetate fraction (1 :4) of Tarjuna was found to be active against Shigella dysenteriae, Shigella jIexneri, Shigella sonnei,Escherichia coli and S.aureus; Pet. ether-Ethyl acetate fraction (2: I) of methanol extract of R.serpentina was active against Saureus: Antibacterial compound HAl then separated from the Ethyl acetate fraction of Methanol extract of H.antidysenterica with the help of preparative thin layer chromatography. Methanol extracts of Tarjuna and R.serpentina were then purified with the help of column chromatography followed by PTLC to yield compounds TA" and RS. Compound HAl was found to be active against S. aureus, TA, was found to be active against Shigella dysenteriae, Shigella jIexneri, Shigella sonnei,Escherichia coli and S.aureus; and compound RS showed antibacterial activity against Saureus. Three antibacterial compounds were then characterized by physical, chemical and spectroscopic analysis. Compound HAl was steroidal alkaloid with-C=N group ; viii compound TA3 was flavone with ketone group; and compound RS was alkaloid with phenyl hydroxyl group, aryl ether group and carboxylic acid group. Minimum Inhibitory Concentration (MICs) of compounds TAl for Shigella dysenteriae was 640 !1g/ml, that of compound TAl for Sflexneri was 320!1g/ml, that of compound TAl for Ssonnei was 960!1g/ml, that of compound TAl for E.coli was 640!1g/ml and that of compounds HA"TAl and RS for Saureus were 320!1g/ml,320!1g/m! and 160!1g/ml. respectively. The Minimum Bactericidal Concentration (MBC)of compound TAl Shigella dysenteriae was 790!1g/ml, that of compound TAl for Shigella flexneri was 780!1g/ml and that of compound TAl for Ssonnei was J075!1g/ml, that of compound TAl for E.coli was 775!1g/ml, and that of compounds HA"TAl and Rs for Saureus were 8JO!1g/ml,730!1g/ml and 670!1g/ml respectively.
Computer modeling and design provisions of shear wall building
(Department of Civil Engineering, 2002-09) Rafiqul Islam, Md.; Shafiul Bari, Dr. Md.
In recent years there has been a considerable increase in the number of tall building, both residential and commercial purpose and the modern trend is towards taller and more slender structures on a small piece of valuable land. In our country most of this tall building is attributing shear wall to resist the effect of lateral load like wind load, earthquake load, blast forces etc. As construction of tall building is relatively new phenomenon in Bangladesh, most of the practicing civil engineers have little knowledge about the analysis and design of shear wall building. During the analysis of a frame-wall structure, most of the cases the designer faces problem in modeling of shear and core wall. So the prime objective of this thesis is to carry out a comparative study among different modeling techniques of shear wall to suggest a simple guideline within reasonable accuracy of result. For this purpose various model has been prepared on an idealized problem and the results obtained from two-dimensional model is compared with those obtained from three-dimensional model. Analysis on two-dimensional model is performed by MICROFEAPand three-dimensional analysis is performed by SAP90 and STAAD-III. It is also studied that whether the results of the model vary significantly with the increase of height of the building. Moreover, effect on moment carrying capacity of shear wall due to change of its moment of inertia is checked. Like the modeling and analysis of shear wall the design engineer also face trouble in designing it, because the code provisions are not very much specific about shear wall. Also the code requirements for shear wall are dispersed in various chapters. Code provisions in Bangladesh National Building Code (BNBC), American Concrete Institute (ACI) code, Uniform Building Code (UBC) and British Code of Practice (BS 8110) are studied in this thesis and a straightforward guideline is suggested for the design of shear wall.
Corporate Social Responsibility Practices of Southeast Bank Ltd.
(Daffodil International University, 2020-10-06) Rafiqul Islam, Md.
This paper examine how the Southeast Bank ltd. Exercises of Corporate Social Responsibility (CSR) in Bangladesh. Keeping pace with the global movement, CSR is seen as a new source of competition for Bangladesh's banking sector. Banks in Bangladesh practice not only improving community relations but also as a source of significant commercial benefits. Southeast Bank Ltd. Practices CSR under the rules and regulations of Bangladesh Bank. The study is based on the 2018 Annual Report of the South-East Bank Limited. In this study, southeast bank spent BDT 208.53 million in the year 2018 in the area of education, health, community, development, environment, art and culture, sports etc. The maximum amount of money expenses in schools, colleges and universities in the education sector.
Impact of fibre chromatic dispersion on the performance of a WDM optical ring network
(Department of Electrical and Electronic Engineering, BUET, 1998-05) Rafiqul Islam, Md.
For abstracts please see full text
New method for testing quality of cemented carbide tools and a comparative study of different cemented carbide and high speed steel tools available in the local market.
(Department of Industrial and Production Engineering, BUET, 1989-11) Rafiqul Islam, Md.; Nurul Amin, Dr. A. K. M.
Determination of tool-quality is a very important factor in metal cutting process. Because production rate, production cost, surface finish etc. depend on it. At present in Bangladesh, there is no testing facilities for cemented carbide tools which are most widely used in production. In the present research work, a new quality control method has been developed with which quality of the cemented carbide tool bits can be determined avoiding the lengthy method of tool wear test. Quality of high speed steel tool can also be tested using this method but for work-material apart from steel. A comparative analysis of economic effectiveness of cemented carbide and high speed steel tools have been made and it has been established that the cost of turning a lead screw of a lathe machine with the high speed steel tool is, on the average, two and a half times greater than that of carbide tipped tools at the cutting speed of 80 m/min. It has been further established by experiments that at higher cutting speeds like 100,120,150 mm/min., it is not possible to 'use a high speed steel tool at all for the same purpose.
Rural development and microcredit: a comparative study of conventional microcredit and islamic shariah based microcredit
(Department of Urban and Regional Planning (URP), 2009-07) Rafiqul Islam, Md.; Jahan, Dr. Sarwar
The study entitled, “RURAL DEVELOPMENT AND MICROCREDIT: A COMPARATIVE STUDY OF CONVENTIONAL MICROCREDIT AND ISLAMIC SHARIAH BASED MICROCREDIT” was conducted on three villages namely Sukhati of Newashi Union, Boromani of Bamondanga Union and Shapkhoa of Raigonj Union of Nageswari Upazila, Kurigram. Data were collected through structured questionnaires and Focus Group Discussion (FGD) to identify the qualitative as well as quantitative changes of rural development indicators such as economic, human resource and living environment related parameters of the microcredit beneficiaries as well as non-beneficiaries. The major concern of this study includes the analytical description of impact analysis of conventional and shariah based microcredit on rural development indicators. Thus this study furnishes a wealth of information of the beneficiaries and non-beneficiaries about land and livestock ownership, ownership of other assets, income and savings, housing, education, occupation, family planning, source of drinking water and sanitary latrine. In fact, this comparative study explores the impact of conventional as well as Islamic shariah based microcredit on the rural development indicators of the selected three villages of Nageswari Upazila in Kurigram District. This study reveals that both conventional and Islamic shariah based microcredit have positive impacts on the rural development indicators. This programme has increased the land ownership, income and savings, housing quality, awareness regarding education and family planning, safe drinking water and uses of sanitary latrine. In fact, there has been an exaggeration of impact of conventional microcredit programme on rural development in Bangladesh.
Simple mathematical model of alternations for use in power system stability studies
(Department of Electrical and Electronic Engineering, BUET, 1991-08) Rafiqul Islam, Md.; LutfuI Kabir, Dr. S.M.
For abstracts please see full text
Study on urban signs in Dhaka
(Department of Urban and Regional Planning, 2005-09) Rafiqul Islam, Md.; Islam, Ms. Ishrat
Dbaka, witb 10,7 million population. p05se,ses llLh p'1silJon among tb~ 19 mega cities of th~ world. According to thc projcction, it will be 4th m~ga city of the world WIth 21.1 million population in 2015 (UNFPA Report. 20(3). Dhaka City can be called a city of signs. The nllmbcr of pellplc, commerCIal activities and physical extent of the ~ily arc inel'ea,ing day by day, Along with these, the number of signs i" als'1 increasing. Signs are being used in Bangladesh since 50~-60s of nineteenth century and were being considered as important v)sual elements. Since tlle boom in jute trade at Dbaka in 1854 to till today, approach and strategy of advel1isement is changing continuously, Not '1nly the number of signs ha~ been increased in this city 50 far, but also the design, style, color. technology of sign has been tremend'1usly changed. ln devel'1ped countries, there is a Sign ordinance or eomprehen,ive sign p'1llcy for each of their big cities like Dhaka [0 have overall C'1ntrol on sign. Atthc same time, up to 201l5, in Bangladesh, there is no individual SIb'll ordillance '1r comprehensive sign policy for any of her cities. Even, no research has been conducted to find out a way to control the gl'Owth of sign. In January 2003, only a _"gn policy has been fonnulated by Dhnka City Corporation, which i, rclnted to business signs only, The research was conducted to study urban ~igns of Dhaka and existing rules and regulatIOns regarding urban sign and to study the visual impact of sign on the city and city people from peoples perspective. This shldy was also done to provide some gUIdelines for a comprt:hensive model sign ordinance. The research was conducted on five typical area, of Dhaka City e.g. Mirpur road- Elephant road, University area; Mohakhali-TeJgaon; Gulshan; Old Dhaka and Utlara. This study Jound out the existmg ,;ituation of different issues on sign,; e,g. taxation, challenges of dealing,; in/wIth signs, a snapshot on the physical sccnario of ,;igns, sporadic rules - I'Cb'Uiation" current practice,; regarding sign, Dhaka City Corporation policy on signs, ~iolal1ons of the pohey. people', pcrccption regarding benet,! and adverse C[fect of sign" perccption regarding locaticll1 of SIgnS, means to increase the efficiency 0[' signs etc. The study reveals that the existing rules and regulations regarding Slb'l1Sarc insufficient and spOl'adic; there is no guidelines in any where of the existing p'1lieies and laws '1f Bangladcsh for political sign, banner, festoon, wall "'fiting, content relevancy etc, The ,tudy also reveals that 7% of total signs are poorly nwinlained among the surveyed sign,; total 389 signs (13.71\%) out of 282\ has violated nominal yenkal clearance; Dhaka City CorpOl'ation nuthority keeps only the records of thosc signs from which they eilm rcvcnue; signs nrc placed in the restricted places violating the cXlsting policy; the participant, of the Focus Group DiscUSSlOilShave a number of altemall ve ldeas for increa~mg cfliciency and reducing the l1umber of signs in the city and also for rcuueing visual blight. It is evident from this stuuy that gcneral city dwellers as th~ larget beneficiaries of the signs can play an important role for formulating policies I ordinances through propel' participatIOn. The general people have some consttuctiyc comments and ideas rcgarding desired images of signs for Dhaka Mega City.