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Jamalpur, Bangladesh

The University of Information Technology & science is a university in Baridhara, Dhaka, Bangladesh. Its vice chancellor is Professor Dr. Muhammad Samad. Wikipedia.


Begum Z.,University of Information Technology and Sciences
IFMBE Proceedings | Year: 2013

With a view to evaluate the Quality Assurance status of radiodiagnostic facilities some basic elements of QA program such as frequency of different procedures, reject/repeat analysis, record keeping and justification of each procedure were evaluated in around 100 Hospitals/Clinics in four districts including Dhaka, the Capital City of Bangladesh. Also to check the optimal performance of the machines some of the essential Quality Control (QC) tests those can be performed with minimum cost and efforts on a regular basis were studied in this paper. The following important QC parameters were checked: kVp Accuracy Test, Output Reproducibility, Linearity/mA, mR/mAs, Reproducibility/kVp and Reproducibility/time, Accuracy/time, Focus Film Distance (FFD), Half-Value Layer (HVL). It was observed that effective QA program has yet not been introduced in most of the diagnostic departments of Bangladesh. Fundamental radiation protection principles of medical exposure Justification and Optimization are not taken into consideration. Frequency analysis or reject/repeat analysis is not being done, record keeping is not being practiced and also no sort of routine/occasional QC tests are being introduced in the hospitals/clinics. So, it is most likely that the patients and general public are being exposed with unwanted radiation exposure. Hence, steps should be taken to make awareness among the Radiological departments about the necessity of adapting QA/QC programs in the facilities. © 2013 Springer-Verlag. Source


Hasan M.M.,University of Information Technology and Sciences
Wireless Personal Communications | Year: 2013

Orthogonal frequency division multiplexing (OFDM) is perhaps the most spectrally efficient, robust transmission technique discovered so far for communication systems, and it also mitigates the problem of multipath environment. High peak-to-average power ratio (PAPR) has always been a major drawback of the OFDM systems. In this article, a new precoding technique has been proposed based on Vandermonde-like matrix (VLM) and selective mapping (SLM) to reduce PAPR in OFDM systems. VLM precoding reduces the autocorrelation of the input sequences while SLM takes an advantage of the fact that the PAPR is very sensitive to phase shifts of the signal. The main advantage of this proposed scheme is to achieve a significant reduction in PAPR without increasing the system complexity. Computer simulations show that, the proposed method outperforms the existing precoding techniques without degrading the error performance of the system. © 2013 Springer Science+Business Media New York. Source


Hasan M.M.,University of Information Technology and Sciences
Wireless Networks | Year: 2014

High peak-to-average power ratio (PAPR) is still one of the major problems in orthogonal frequency division multiplexing (OFDM). In this article, a new precoding method is proposed and analyzed based on complex Vandermonde matrix (CVM). The reduction in PAPR of the OFDM signal is obtained using the decorrelation property of CVM which removes any redundancy from the input sequence and can be a very effective for PAPR reduction. Also, the phase-rotation property of CVM takes an advantage of the fact that the PAPR is very sensitive to phase-shifts of the signal. It is shown that the proposed precoding outperforms most of the powerful precoding techniques and can achieve a PAPR gain up to 6.5 and 7.4 dB for IEEE 802.11a and DVB-T OFDM systems respectively. Moreover, CVM precoding does not change power spectral levels or error performances when compared with the normal OFDM systems, also it does not increase the computational complexity when compared with the existing precoding methods. It is shown that the performance of the proposed precoding is independent of modulation schemes and the number of subcarriers. The proposed CVM precoding also takes advantage of the frequency variations of the communication channel and can provide considerable performance gain in fading-multipath channels. © 2014 Springer Science+Business Media New York. Source


Muhury L.,University of Information Technology and Sciences | Habib A.H.M.A.,Chittagong University of Engineering and Technology
Proceeding of the 15th International Conference on Computer and Information Technology, ICCIT 2012 | Year: 2012

In the age of electronic systems it is important to acquire and control information from everywhere. Here we present a novel secure real time method to control device. We summarizes a study conducted to examine the feasibility of implementing Global System for Mobile Communications (GSM), using Duel Tone Multi-Frequency (DTMF) as an alternative means of communication to Radio Frequency (RF) to control electrical appliances. In remote communication, DTMF signal can replace RF signal for the advantage of simplicity and audibility. A user can send DTMF tone to control home appliances or machines in industries. Any GSM mobile phone can be employed to send DTMF tone. The advantage of this system is the use of GSM technology for communication and at a time control of many devices. This paper deals with the design and experimentation, which can be useful for the people who are working in research laboratory, industry & education in the field of Communication, Control, wireless technology etc. © 2012 IEEE. Source


Hasan M.M.,University of Information Technology and Sciences
Circuits, Systems, and Signal Processing | Year: 2014

Orthogonal frequency division multiplexing (OFDM) is perhaps the most spectrally efficient method discovered so far for communication systems and yet have an excellent immunity against multipath fading and inter-symbol interference. One of the major drawbacks of OFDM systems is their high peak-to-average power ratio (PAPR), which degrades system performance when nonlinear high power amplifiers (HPA) are employed. In this article, a new companding technique based on gamma correction (GC) function is proposed and analyzed. Through extensive computer simulations, it is shown that the proposed technique outperforms the previously suggested A-law and μ-law companding methods for PAPR reduction. A thorough investigation of GCC companding is presented in terms of computational complexity (CC), complementary cumulative distribution function (CCDF), power spectral density (PSD), and bit-error-rate (BER). It is also shown that the proposed method is independent of modulation schemes and can be applied to any number of subcarriers. © 2013 Springer Science+Business Media New York. Source

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