Volume 3, Number 1, (2011) http://dspace.mist.ac.bd:8080/xmlui/handle/123456789/35 2026-04-26T00:20:29Z 2026-04-26T00:20:29Z Kumar Dhar, Pranab Ibrahim Khan, Mohammad Chowdhury, Sujan http://dspace.mist.ac.bd:8080/xmlui/handle/123456789/210 2015-09-18T03:47:38Z 2011-02-01T00:00:00Z

An Efficient Image Watermarking System Based On Error Correcting Codes In Dct Domain 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.

2011-02-01T00:00:00Z Jahan Rashid Pinky, Lubna Naim Rakib Ahmed, Abu http://dspace.mist.ac.bd:8080/xmlui/handle/123456789/209 2015-09-18T03:47:39Z 2011-02-01T00:00:00Z

Modeling Of Photoelastic Constant Dependent On Arbitrary Crystal Orientation 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.

2011-02-01T00:00:00Z Das, C. K. Das, N. K. Islam, M. M. Sazzad Hossain, S.M. http://dspace.mist.ac.bd:8080/xmlui/handle/123456789/208 2015-09-18T03:47:37Z 2011-02-01T00:00:00Z

Virtual Power Plant As A Remedy To The Power Crisis Of Bangladesh: A Case Study-Cuet 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.

2011-02-01T00:00:00Z Moinul Islam, Md. Saiful Islam, Dr.Md. Aftabur Rahman, Md. http://dspace.mist.ac.bd:8080/xmlui/handle/123456789/207 2015-09-18T03:47:36Z 2011-02-01T00:00:00Z

Strength Behavior Of Mortar Using Slag As Partial Replacement Of Cement 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.

2011-02-01T00:00:00Z