Browsing by Author "Wahiduzzaman, Md."

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Analysis of Linear Cryptanalysis for Lightweight AES Block Cipher
(Daffodil International University, 2021) Sarkar, Nur Mohammad; Wahiduzzaman, Md.; Abdur Raihan, Mohammad
This research work represents the analysis of linear cryptanalysis of lightweight AES block ciphers. The linear cryptanalysis is widely known as one of the primary tools for S- Box security design. The AES is effective for fast, light and hardware reduction systems whereas the lightweight algorithm is used for smooth application. Therefore, the S Box is usually used to obscure the connection between the main text and the cipher text. This S Box design is basically two types: LUT S-Box and composite S-Box. The composite S Box design is based on Affine Transformation (AT) where different affine matrices and constants are used to enhance the security of the design. Hence, this research is focused on using different affine constants to find affine transformation and linear cryptanalysis of different S Boxes to examine the linear attacks on cipher text. The 4X4 affine matrix and 16 different affine constants have been used for this work. The result has been evaluated on strong linear values among 16 different constants. Finally, the S-Box has been proposed according to the best linear values which are more effective and sensible in data protection on lightweight AES block ciphers.
Availability of Groundwater for Drinking Purpose in Khulna City
(Khulna University of Engineering & Technology (KUET), Khulna, Bangladesh, 2009-11) Wahiduzzaman, Md.; Bari, Prof. Dr. Quazi Hamidul
Khulna, the industrial and port city, is the third largest city of Bangladesh which is situated in the south west part of Bangladesh and lies in the delta of the Ganges. The city itself stretches 15 km along the River Bhairab and Rupsha, covering the area of approximate 46 sq. km. having population around 1 million. The scarcity of water has been augmented gradually owing to increasing resettlement from the surrounding districts for rapid urbanisation and industrialisation. On the other hand the water supply situation has been aggravated due to lack of necessary parallel growth in the water supply infrastructure. This study focused on identification of the number of aquifers and potentiality the aquifers by investigating the available geological, hydro-chemical, and hydrodynamic parameter of the aquifers. Comprehensive geological cross-sections and a conceptual model of the deep aquifer have been developed using lithologs of previous LGED study (MSP 2005) and DPHE (Rus, 1985) investigation in Khulna area. The estimation of annual ground water recharges in the most potential aquifer has been performed to identify the exploitable (usable) locations for drinking purposes. Data on lithologs, static water level, electrical conductivity, temperature, pH, arsenic, and pumping tests in different aquifers have been collected and analyzed in order to fulfill the study objectives. The data of two special ground water monitoring sessions in 2009 has been collected in order to assess the present situation, comparison to the situation in 2005, for the deep aquifer in Khulna. Three different aquifers have been identified such as upper shallow, shallow and deep aquifer. It seems that, in some areas the upper shallow aquifer is connected with shallow aquifer. The observed fluctuating water heights for deep, shallow and upper aquifers are 2.13 m, 2.26 m and 1.97 m, respectively. It has been observed that the transmissivity values of deep aquifer varies from l.3x10·3 m2/sec to 7.lxlff2 m2/sec and the storage coefficient varies from 9.7x10-4 to 4.7x10·3. It is also observed that the average temperature of KWASA production wells in the central part of the city is much higher than those in other part of the study area. There is no indication of increase of average temperature neither in KWASA production well nor in MSP monitoring well since 2005.There is no increase in the average EC value for the MSP monitoring wells since 2005. The average SWL in the project area was - 1.42 m in 2005 and - 2.06 m in 2009 it from mean sea level (MSL), thus the net average declination of SWL in last four years is 0~63 m. Most important observation is that, this mass of declination of the SWL has affected neither EC nor Temperature. Note that the average temperature of water in the central area is higher than the normal range. For highest static water level in the month of October, usable recharge has been obtained as about 40,470 m3/day which is slightly more than the average abstraction rate of 40,000m3/day while for lowest static water level in the month of April, usable recharge has been obtained as about 36,070 m3/day. It is true that the complete dependency on ground water for Khulna city water supply, with the present aquifer system, may not sustainable for long term abstraction planning. Since the fresh water resource of the deep aquifer is limited and cannot sustain substantial increase in abstraction rates, an additional volume of drinking water may be derived from blending of water of different sources. The Electrical Conductivity of the deep aquifer near and south of the city centre is very low. There might have few solutions to mitigate the water crisis of the city; i) small quantity of moderately mineralised water from the shallow aquifer can be mixed with water from deep aquifer within the acceptable limit this will increase substantial amount of overall water production. It can be reminded that the water quality of the shallow aquifer is good (and arsenic free) except for the high concentration of saline and with some iron. Iron of the shallow aquifer might be removed by simple aeration and filtration technique. ii) use of surface water for the period of low salinity in the surface water (7-8 months' time in the Bhairab- Rupsha River) to preserve and restrict the abstraction from deep aquifer for those period and supply the ground water for the period of high saline in the surface water (February to June). iii) under WASA Act: 1996, KWASA can impose control over the industrial abstraction from the deep aquifer. In order to restrict abstraction from deep aquifer, for industrial use, KWASA can provide them alternate water through the surface water sources throughout the year.
Availability of Groundwater for Drinking Purpose in Khulna City
(Khulna University of Engineering & Technology (KUET), Khulna, Bangladesh, 2009-11) Wahiduzzaman, Md.; Bari, Prof. Dr. Quazi Hamidul
Khulna, the industrial and port city, is the third largest city of Bangladesh which is situated in the south west part of Bangladesh and lies in the delta of the Ganges. The city itself stretches 15 km along the River Bhairab and Rupsha, covering the area of approximate 46 sq. km. having population around 1 million. The scarcity of water has been augmented gradually owing to increasing resettlement from the surrounding districts for rapid urbanisation and industrialisation. On the other hand the water supply situation has been aggravated due to lack of necessary parallel growth in the water supply infrastructure. This study focused on identification of the number of aquifers and potentiality the aquifers by investigating the available geological, hydro-chemical, and hydrodynamic parameter of the aquifers. Comprehensive geological cross-sections and a conceptual model of the deep aquifer have been developed using lithologs of previous LGED study (MSP 2005) and DPHE (Rus, 1985) investigation in Khulna area. The estimation of annual ground water recharges in the most potential aquifer has been performed to identify the exploitable (usable) locations for drinking purposes. Data on lithologs, static water level, electrical conductivity, temperature, pH, arsenic, and pumping tests in different aquifers have been collected and analyzed in order to fulfill the study objectives. The data of two special ground water monitoring sessions in 2009 has been collected in order to assess the present situation, comparison to the situation in 2005, for the deep aquifer in Khulna. Three different aquifers have been identified such as upper shallow, shallow and deep aquifer. It seems that, in some areas the upper shallow aquifer is connected with shallow aquifer. The observed fluctuating water heights for deep, shallow and upper aquifers are 2.13 m, 2.26 m and 1.97 m, respectively. It has been observed that the transmissivity values of deep aquifer varies from 1.3x10 3 m2/sec to 7.1x10 2 m2/sec and the storage coefficient varies from 9.7x10 4 to 4.7x10. It is also observed that the average temperature of KWASA production wells in the central part of the city is much higher than those in other part of the study area. There is no indication of increase of average temperature neither in KWASA production well nor in MSP monitoring well since 2005.There is no increase in the average EC value for the MSP monitoring wells since 2005. The average SWL in the project area was - 1.42 m in 2005 and - 2.06 m in 2009 it from mean sea level (MSL), thus the net average declination of SWL in last four years is 0.63 m. Most important observation is that, this mass of declination of the SWL has affected neither EC nor Temperature. Note that the average temperature of water in the central area is higher than the normal range. For highest static water level in the month of October, usable recharge has been obtained as about 40,470 m3/day which is slightly more than the average abstraction rate of 40,000m3/day while for lowest static water level in the month of April, usable recharge has been obtained as about 36,070 m3/day. It is true that the complete dependency on ground water for Khulna city water supply, with the present aquifer system, may not sustainable for long term abstraction planning. Since the fresh water resource of the deep aquifer is limited and cannot sustain substantial increase in abstraction rates, an additional volume of drinking water may be derived from blending of water of different sources. The Electrical Conductivity of the deep aquifer near and south of the city centre is very low. There might have few solutions to mitigate the water crisis of the city; i) small quantity of moderately mineralised water from the shallow aquifer can be mixed with water from deep aquifer within the acceptable limit this will increase substantial amount of overall water production. It can be reminded that the water quality of the shallow aquifer is good (and arsenic free) except for the high concentration of saline and with some iron. Iron of the shallow aquifer might be removed by simple aeration and filtration technique. ii) use of surface water for the period of low salinity in the surface water (7-8 months' time in the Bhairab- Rupsha River) to preserve and restrict the abstraction from deep aquifer for those period and supply the ground water for the period of high saline in the surface water (February to June). iii) under WASA Act: 1996, KWASA can impose control over the industrial abstraction from the deep aquifer. In order to restrict abstraction from deep aquifer, for industrial use, KWASA can provide them alternate water through the surface water sources throughout the year.
Comparison among Different Beam Forming Algorithms used in Smart Antenna System for 3G+ Mobile Communications
(Department of Electrical and Electronic Engineering, Islamic University of Technology (IUT), Board Bazar, Gazipur-1704, Bangladesh, 2012-11-15) Islam, Md. Rezwanul; Wahiduzzaman, Md.; Tanmoy, M. M. Reazul Haque
Smart antenna manipulates the impinging signals on various antenna elements through array processing so that the main lobe is formed towards the desired direction and nulls are placed towards the interference or unwanted directions. Direction of Arrival (DOA) estimation is an important part of direction of arrival based beam forming. The direction of arrival algorithm computes the angle of arrival of all impinging signals. A systemic study of smart antenna system and comparison of the performance of the Bartlett and MUltiple SIgnal Classification(MUSIC) DOA algorithms along with different non blind beam forming algorithms through simulation have been extensively analyzed in this thesis work. Our comparative analysis shows that MUSIC algorithm is highly accurate and stable and provides high angular resolutions compared to Bartlett algorithm. So MUSIC algorithm can be widely used in mobile communication to estimate the DOA of arriving signals. Among LMS, SMI, RLS beam forming algorithms RLS algorithm is the fastest to converge the weights through least computational complexity.
Job Satisfaction and Professional Commitment: A Study on Bangladesh Civil Service General Education Cadre
(University of Rajshahi, 2016) Wahiduzzaman, Md.; Sadique, Md. Zafor
Job satisfaction and Professional commitment among public sector employees, specifically the education sector is becoming an area of major concern as highlighted by recent research. As there is no study found whether BCS general education cadre officers are satisfied with job and committed to their profession, this study aims to evaluate the levels of job satisfaction and levels of professional commitment of the officers of BCS (Gen. Ed.) cadre and to analyze the factors that impact the job satisfaction and professional commitment of them. Relevant literature has been reviewed to develop a conceptual framework and to identify the variables of the study. Job satisfaction and professional commitment are two dependent variables and identified independent variables are grouped under demographic, HRM, institutional, job stressors and job characteristics. Based on the objectives some hypothesis were developed which have been tested in this study. Both primary and secondary data were used in this study. Primary data were collected using structured questionnaire by survey method from 374 BCS general education cadre officers from different types of government academic institutions and education management office. Four numbers of FGD have been conducted to justify the data. Secondary data was collected from related thesis, journals, books, authentic websites, newspaper etc. Data were analyzed using Statistical Package for Social Sciences (SPSS). The findings indicate the officers of BCS (Gen. Ed.) cadre are moderately satisfied considering every aspect of job into account on an average. But specifically, they are not satisfied regarding extrinsic and intrinsic aspects of their job. Results also indicate that high level of Affective Professional Commitment (APC), moderate level of Continuous Professional Commitment (CPC) and Normative Professional Commitment are present among the education cadre officers. The independent variables (Demographic, HRM, Institutional, Job stressors and characteristics) strongly impact the job satisfaction and professional commitment of the BCS (Gen. Ed.) cadre officers. Among the demographic factors, designation, appointment type, location of Institute, occupational group, age, and job tenure are significant influencing factors of job satisfaction and professional commitment of the officers of BCS (Gen. Ed.) cadre. Female officers are more satisfied than male officers. HRM factors are most significant predictors of job satisfaction and professional commitment of the BCS general education officers. The respondents are relatively satisfied with recruitment & selection procedure and their job security. On the other hand, they are dissatisfied with posting & transfer, promotion, training, and performance appraisal system of the education cadre. Result revealed that salary & benefits, career development, job security, promotion, justice & equity and posting & transfer factors have significant impact on job satisfaction and professional commitment. The study has found that, from institutional factors interpersonal relation among the officers is good and logistic support, morality are important significant influencing factors of job satisfaction and professional commitment. Among the job related variables, job conflict, autonomy, task variety and support from the boss are most significant predictors of job satisfaction and professional commitment of BCS (Gen. Ed.) cadre officers. Finally, the results of this study are significant for policy and practice. It may assist policy formulation and implementation to enhance job satisfaction and professional commitment of the BCS (Gen. Ed.) cadre officers which ultimately improve performance.
Optimizing channel capacity for B5G with deep learning approaches in MISO-NOMA-HBF and BFNN 1 of 1
(Institute of Advanced Engineering and Science, 2024-06-25) Masud, M.A.; Al Amin, A.,; Islam, Md.S.,; Mostafa, V.; Wahiduzzaman, Md.
This study proposes the integration of a beamforming neural network (BFNN) and multiple-input single-output based non-orthogonal multiple access (MISO-NOMA) with hybrid beamforming (HBF) for cell edge users (CEU) in a millimeter wave (mmWave)-based beyond 5G cellular communication system. This system is referred to as MISO-NOMA-HBFBFNN. The proposed scheme has been implemented to support multiple users simultaneously and also to considerably enhance and significantly improve the overall the sum channel capacity (SC) and user channel capacities. Additionally, the simulation results demonstrate the superiority of the proposed MISO-NOMA-HBF-BFNN scheme over the existing MISO-NOMA with HBF and MISO-OMA with HBFBFNN based schemes in terms of user capacities and SC
Pharmacy department of BRACU opens advanced research lab
(Varsity Admission.com, 2012-05-11) Wahiduzzaman, Md.
The Long-Term Effects of Childhood Circumstances on Older Individuals: A Systematic Review
(John Wiley & Sons, 2024-03-28) Parvin, Mst. Rina; Johra, Fateha Tuj; Akter, Fazila; Wahiduzzaman, Md.; Akter, Khadiza; Das, Mousumi; Mondal, Sujit; Debnath, Mitun; Ullah, Mohammad; Rony, Moustaq Karim Khan
Childhood experiences are known to shape individuals' development and can influence various aspects of life later on. Understanding the long-term effects is crucial for informing interventions and policies aimed at promoting healthy aging. This review aimed to explore the long-term effects of childhood experiences on older individuals. This systematic review comprised three distinct phases. Firstly, a systematic review was conducted, exploring databases such as Google Scholar, PubMed, EMBASE, PsycINFO, and the Web of Science. Out of the 2116 studies initially identified, 24 studies were selected based on the inclusion criteria. Secondly, these inclusion criteria were applied to ensure that the chosen studies specifically delved into the connection between childhood experiences and outcomes in older individuals. Finally, data extraction and synthesis techniques were employed to analyze findings, facilitating the drawing of conclusions concerning the enduring impacts of childhood experiences on the well-being of older individuals. The review's findings revealed how negative experiences in childhood continue to affect older individuals in various ways. These early-life events have far-reaching consequences, profoundly impacting their physical health, making them more susceptible to chronic diseases and weakening their immune system. Additionally, they affect mental health, leading to conditions like depression, anxiety, and substance abuse. Cognitive function is also affected, resulting in memory problems and cognitive decline. Furthermore, these experiences impact social relationships, affecting trust, emotional control, and social isolation in later life. This review highlighted the enduring influence of childhood circumstances on the health and well-being of older individuals. Policymakers and health care practitioners should consider these findings when developing strategies to support healthy aging and mitigate the long-term effects of adverse childhood experiences.
The long-term effects of childhood circumstances on older individuals: A systematic review
(Scopus, 2024-04-12) Parvin, Mst. Rina; Johra, Fateha Tuj; Akter, Fazila; Wahiduzzaman, Md.; Akter, Khadiza; Das, Mousumi; Mondal, Sujit; Debnath, Mitun; Ullah, Mohammad; Rony, Moustaq Karim Khan
Childhood experiences are known to shape individuals' development and can influence various aspects of life later on. Understanding the long-term effects is crucial for informing interventions and policies aimed at promoting healthy aging. This review aimed to explore the long-term effects of childhood experiences on older individuals. This systematic review comprised three distinct phases. Firstly, a systematic review was conducted, exploring databases such as Google Scholar, PubMed, EMBASE, PsycINFO, and the Web of Science. Out of the 2116 studies initially identified, 24 studies were selected based on the inclusion criteria. Secondly, these inclusion criteria were applied to ensure that the chosen studies specifically delved into the connection between childhood experiences and outcomes in older individuals. Finally, data extraction and synthesis techniques were employed to analyze findings, facilitating the drawing of conclusions concerning the enduring impacts of childhood experiences on the well-being of older individuals. The review's findings revealed how negative experiences in childhood continue to affect older individuals in various ways. These early-life events have far-reaching consequences, profoundly impacting their physical health, making them more susceptible to chronic diseases and weakening their immune system. Additionally, they affect mental health, leading to conditions like depression, anxiety, and substance abuse. Cognitive function is also affected, resulting in memory problems and cognitive decline. Furthermore, these experiences impact social relationships, affecting trust, emotional control, and social isolation in later life. This review highlighted the enduring influence of childhood circumstances on the health and well-being of older individuals. Policymakers and health care practitioners should consider these findings when developing strategies to support healthy aging and mitigate the long-term effects of adverse childhood experiences