Galaxy (Dhaka): The Annual Technical Journal of MIST

Browse

Filters

201111

Settings

Search Results

Now showing 1 - 10 of 11
  • Thumbnail Image
    Item
    An Efficient Image Watermarking System Based On Error Correcting Codes In Dct Domain
    (R&D Wing, MIST, 2011-02) Kumar Dhar, Pranab; Ibrahim Khan, Mohammad; Chowdhury, Sujan
    Digital watermarking has drawn extensive attention for copyright protection of multimedia data. This paper proposes a new watermarking system for digital images using efficient systematic linear block codes (SLBC) in discrete cosine transform (DCT) domain. The proposed watermarking system using SLBC generates a code sequence of {0, 1} that provides error correction capabilities and then replaces it with a binary watermark sequence of {-1, 1}. This achieves more robust invisible image watermarks and requires a small storage unit for binary sequence numbers. The generated watermark sequence is then used as an input for our proposed watermarking system which consists of watermark embedding process and watermark detection process. Experimental results indicate that the invisible watermark embedded with the proposed system are very robust against various kinds of attacks such as white Gaussian noise, JPEG compression, median, and mean filtering, by showing similarity values ranging from 0.7 to 0.8.
  • Thumbnail Image
    Item
    Modeling Of Photoelastic Constant Dependent On Arbitrary Crystal Orientation
    (R&D Wing, MIST, 2011-02) Jahan Rashid Pinky, Lubna; Naim Rakib Ahmed, Abu
    A mathematical model is proposed to determine the photoelastic constants in arbitrary crystal orientation of Zincblende crystal structure. Tensor rotation technique is applied using Euler’s rotation theorem to develop the model. The model is applicable to evaluate photoelastic constants in terms of P11-P12 and P44 in any crystal plane by controlling the rotation angle using the model. P11-P12 and P44 are calculated for Silicon crystal and found that the values of these constants are strongly dependent on crystal orientations. The outcome of this research enables us to evaluate quantitative amount of strain in polycrystalline silicon material (solar cell material) using Scanning Infrared Polariscope.
  • Thumbnail Image
    Item
    Virtual Power Plant As A Remedy To The Power Crisis Of Bangladesh: A Case Study-Cuet
    (R&D Wing, MIST, 2011-02) Das, C. K.; Das, N. K.; Islam, M. M.; Sazzad Hossain, S.M.
    A virtual power plant is a cluster of distributed generation installations (such as microchip, wind-turbines, small hydro, back-up genets etc.) which are collectively run by a central control entity. The concerted operational mode shall result in an extra benefit as to deliver peak load electricity or load following power at short notice. Bangladesh is facing acute power crisis like other developing countries. As we have limited resources we have to think economically.VPP is playing good role in European & American market. So we have taken VPP as a solution for power crisis. In this thesis, we have taken CUET as a reference model. To solve the power crisis in CUET & to supply power to the main grid a small virtual power plant is designed .Whole CUET is divided into three regions for designing purpose. By using MATLAB simulink environment machine characteristic curves are derived & cost is calculated.
  • Thumbnail Image
    Item
    Strength Behavior Of Mortar Using Slag As Partial Replacement Of Cement
    (R&D Wing, MIST, 2011-02) Moinul Islam, Md.; Saiful Islam, Dr.Md.; Aftabur Rahman, Md.
    This paper presents an experimental investigation carried out to study the effects of Ground Granulated Blast Furnace Slag (GGBFS) on strength development of mortar and the optimum use of slag in mortar. Cement was partially replaced with seven percentages (10%, 20%, 30%, 40%, 50%, 60% and 70%) of slag by weight. Ordinary Portland cement (OPC) mortar was also prepared as reference mortar. A total of 400 cube and briquet mortar specimens were cast and compressive as well as tensile strength of the mortar specimens were determined at curing age of 3, 7, 14, 28, 60, 90 and 180 days. Test results show that strength increases with the increase of slag up to an optimum value, beyond which, strength values start decreasing with further addition of slag. Among the seven slag mortars, the optimum amount of cement replacement is about 40%, which provides 19% higher compressive strength and 25% higher tensile strength as compared to OPC mortar.
  • Thumbnail Image
    Item
    Challenges Of Globalization: How Bangladesh Can Adapt Itself To Reap The Best Benefits In The 21st Century
    (R&D Wing, MIST, 2011-02) Sharif Md Abul Hussain Dir, Lt Colonel
    The study investigates specific information regarding the challenges of globalization faced by Bangladesh and how it should prepare itself to coup with the challenges. The result suggest that Bangladesh is not in comfort in coping with the winds of globalization, as it has less access to and use of different opportunities living at the margin in the hierarchies of global order with low technological base, poor infrastructures and governance in most arenas. The study also suggest that Bangladesh needs to be engaged with all its development partners in a healthy and constructive process of interaction on stabilization, reform programme and other critical issues like national capacity building, competitiveness, political stability, cross border terrorism, arms and drug trafficking, climate change and environmental degradation. The policy implication is that various economic policy orientation and utilization of resources should be as such that they can supplement economic growth in a sustainable manner and create avenues for employment.
  • Thumbnail Image
    Item
    Design Aid For Continuous Beams
    (R&D Wing, MIST, 2011-02) Khuda, S.N.; Anwar, A.M.M.T.
    Analysis and design of beam is still an important part in Structural Engineering practice. As a major component in structure, it demands due attention and accuracy. At the same time engineers need to achieve economy in time and cost in the design of beams.To assist designers moment coefficients are developed for continuous beams in this work. Existing ACI moment coefficients are applicable only under certain conditions and have some limitations. This study is an attempt to develop moment coefficients for beams which will be applicable beyond ACI limitations. Comparison of developed coefficients with corresponding ACI coefficients has been done and a satisfactory agreement is found. However, ACI coefficients are found to be conservative. Additionally design tables are developed for selection of RC beam section and reinforcement when design bending moment and shear are available. SAP2000 has been used for analysis of beams during the study. Models are used to generate exact moment coefficients for beams of different span ratios and spans under uniform loading. The moment coefficients and design tables generated in this work will be useful for practicing engineers for quick design.
  • Thumbnail Image
    Item
    Developing A Smart Control System Of Electrical Appliances By Computer Interfacing
    (R&D Wing, MIST, 2011-02) Das, N.K.; BN, Capt. M.Ziauddin Alamgir; Das, C.K.; Hasan, M. M.; Rahman, M. M.; Alam, M. F.
    The use of computer interfacing systems for controlling the device is spreading at an increasingly fast pace, with analogous wired system being substituted by computer interfaced systems alternatives in growing number of industries. As the technology progress many control system have been developed ranging from high end stuff to our common daily life. The main objective of this project is to develop a roadmap on communication and control technologies for distributed electrical equipments. Equipments located at any remote place can be monitored and controlled. The process is mainly to communicate between the two remote controlling device and setup connection between devices which are to be controlled. The main hallmark is to get access to the controlling section from any distance location in a convenient way and supervising the system accordingly. The speciality of this project is that the operator will able to control different devices at home/industry by using a single PC. An added advantage of this control system is that the operator will able to know the status of the device to be controlled from a remote place. Here, the algorithm of controlling any kind of electrical equipments is developed. The speeds of a DC motor are controlled as a test case and also monitor the voltage and current during different speed level of the motor.
  • Thumbnail Image
    Item
    Feasibility Of Producing Lightweight Concrete Using Indigenous Materials Without Autoclaving
    (R&D Wing, MIST, 2011-02) Shamsuddoha, M.; Islam, M. M.; M. A., Noor
    This research shows the feasibility and sequential approach for producing lightweight concrete without autoclaving using indigenous ingredients and appropriate technology of Bangladesh. Ingredients were mixed chronologically using trial-and-error method to reduce unit weight. Specific volume principle was utilized to observe the effect of inclusion of cement, water, sand, lime and aluminium in the mixture to achieve the goal. Molds were used to accommodate volumetric expansion of mixture. Both 50 mm and 150 mm cubic specimens were prepared for tests. Density and compressive strength were determined for specimens. Absorption capacity and thermal conductivity were also determined to get the product performance. From the results, it was seen that density and compressive decreased with increased water-cement ratio. Volumetric expansion was high for higher volume surface ratio. Finally, lightweight concrete with density, compressive strength and thermal conductivity within range of 700-1000 kg/m3, 0.5-2.0 MPa and 0.2-0.5 W/m-k respectively was produced.
  • Thumbnail Image
    Item
    Development Of Design And Manufacturing Of A Fixed Wing Radio Controlled Micro Air Vehicle (Mav)
    (R&D Wing, MIST, 2011-02) Hossain, M A; Hasan, F; Seraz, A F M T; Rajib, S A
    Micro Air Vehicles (MAVs) are a new type of aircraft maturing day by day and have reached unprecedented levels of growth recently. Similarly to larger Unmanned Air Vehicles (UAVs), MAVs have enormous potential in applications, both military and civilian, like reconnaissance over battlefields and surveillance of urban areas, data relay, air sampling etc. This article describes the development and selection of a fixed wing MAV with the analysis of simulated results. High wing theory with NACA 4412 aerofoil’s analytical data has been used to practically predict the performance of the MAV.
  • Thumbnail Image
    Item
    Power Line Communication An Essential Tool For Digital Bangladesh
    (R&D Wing, MIST, 2011-02) M Mahbubur Rahman, Cdr BN; Eliasinul Islam, Md.
    An estimation for the power line communications (PLC) for Bangladesh is made referring various technical research papers and current Journals. The aim of this study is to identify essential aspect of the power line communications for both domestic and outdoor application and the use of consumer communication when various possible services are developed worldwide commercially [1,9]. Possible services, bandwidth, service area, quality, reliability, and the cost are also taken into considerations. The signal in a transmission line is impaired by the presence of unwanted extraneous signals (noise and interference) on the line. The frequency dependent characteristics of the transmission line are also responsible to impair the transmission of signals along the lines. Noise and interference, with its presence tends to impede the reception of the desired signal and is usually the limiting factor in its detection. Noise is usually composed of randomly occurring voltages, which are unrelated in phase or frequency and may sometimes be of a very peak in nature. Interference on the other hand is usually more structured than noise since it arises as unwanted coupling from just a few signals in the network. In this paper a brief discussion of noise in a power line environment and need for power line communication in Bangladesh is presented as an essential tool for digital Bangladesh.