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An efficient multi-channel communications scheme for wireless sensor network
Shariful Islam,Muhammad Mahbub Alam,Choong Seon Hong 한국정보과학회 2010 한국정보과학회 학술발표논문집 Vol.37 No.2B
This paper presents a multi-channel communications system for wireless sensor networks (WSNs), referred to as Load-adaptive practical multi-channel communications (LPMC). LPMC estimates the active load of a channel at the sink, and dynamically adds or removes channel based on the estimated load. The nodes in a path use the same channel; and therefore, they do not need to switch channels to receive or forward packets. Furthermore, LPMC updates the routing path to balance the loads of the channels. LPMC is evaluated by simulation in NS-2, and the results demonstrate that it can effectively increase the channel utilization and network throughput, and decrease the delay.
eMCCA: An Enhanced Mesh Coordinated Channel Access Mechanism for IEEE 802.11s Wireless Mesh Networks
Islam, Md. Shariful,Alam, Muhammad Mahbub,Hong, Choong-Seon,Lee, Sung-Won The Korea Institute of Information and Commucation 2011 Journal of communications and networks Vol.13 No.6
In this paper, we present a channel access mechanism, referred to as the enhanced mesh coordinated channel access (eMCCA) mechanism, for IEEE 802.11s-based wireless mesh networks. The current draft of IEEE 802.11s includes an optional medium access control (MAC), denoted as MCCA, which is designed to provide collision-free and guaranteed channel access during reserved periods. However, the MCCA mechanism fails to achieve the desired goal in the presence of contending non-MCCA nodes; this is because non-MCCA nodes are not aware of MCCA reservations and have equal access opportunities during reserved periods. We first present a probabilistic analysis that reveals the extent to which the performance of MCCA may be affected by contending non-MCCA nodes. We then propose eMCCA, which allows MCCA-enabled nodes to enjoy collision-free and guaranteed channel access during reserved periods by means of prioritized and preemptive access mechanisms. Finally, we evaluate the performance of eMCCA through extensive simulations under different network scenarios. The simulation results indicate that eMCCA outperforms other mechanisms in terms of success rate, network throughput, end-to-end delay, packet-loss rate, and mesh coordinated channel access opportunity-utilization.
A Privacy Preserving Authentication Mechanism for Wireless Mesh Networks
Shariful Islam,Abdul Hamid,Choong Seon Hong 한국정보과학회 2007 한국정보과학회 학술발표논문집 Vol.34 No.2D
Due to its ease of deployment, low cost, self-configuring and self-healing capabilities, Wireless Mesh Networks (WMNs) have emerged as a key technology to be used in a wide scale applications in personal, local, campus, and metropolitan areas. Security and more specifically privacy is an important issue in this type of multi-hop WMN which has given a little attention in the research community. We focus on privacy compromise of a mesh client in a community mesh network that may lead an attacker to reveal mesh clients identity, his other profiles and gain information about mobility. In this paper, we have presented an authentication mechanism with the aid of blind signature that ensures a mesh client to anonymously authenticate itself with a nearby mesh router and thereby preserve identity privacy. We have also presented the security and performance analysis of the proposed scheme.
Research Trends in Library and Information Science in Bangladesh: An Analytical Study
Islam, Md. Shariful,Islam, Md. Nazmul,Mondal, Madhob Korea Institute of Science and Technology Informat 2018 Journal of Information Science Theory and Practice Vol.6 No.2
The utmost intention of this work is to identify various field areas which are most prevalent in library and information science education. The study also denotes the rate of tendency on the rapid growth and development of research production among information specialists in Bangladesh. In order to carry out the study, an extensive literature review was carefully done to collect the basic elements of research patterns. It is noted that in the period of 1980-2016, 200 articles were published in library and information science by Bangladeshi researchers in 62 journals. In this article a total of 200 articles were reviewed. The result of the present study shows that the ratio of female authors had fewer contributions than male authors did. The majority of articles were published from the United Kingdom. The study also shows that the largest numbers of articles (19 papers, 9.50%) were published in the Social Science Journal of the University of Rajshahi from Bangladesh. The paper also shows that about 71.50% of papers have been cited while 28.50% of papers did not receive any citation. The present research might be helpful for revealing the country's research trends in library and information science. However, this study may also inspire development of a subject-based indigenous database and can act as an important device for research scholars.
eMCCA: An Enhanced Mesh Coordinated Channel Access Mechanism for IEEE 802.11s Wireless Mesh Networks
Md. Shariful Islam,무하마드마흐법알람,홍충선,이성원 한국통신학회 2011 Journal of communications and networks Vol.13 No.6
In this paper, we present a channel access mechanism,referred to as the enhanced mesh coordinated channel access (eMCCA)mechanism, for IEEE 802.11s-based wireless mesh networks. The current draft of IEEE 802.11s includes an optional medium access control (MAC), denoted as MCCA, which is designed to provide collision-free and guaranteed channel access during reserved periods. However, the MCCA mechanism fails to achieve the desired goal in the presence of contending non-MCCA nodes; this is because non-MCCA nodes are not aware of MCCA reservations and have equal access opportunities during reserved periods. We first present a probabilistic analysis that reveals the extent to which the performance of MCCA may be affected by contending non-MCCA nodes. We then propose eMCCA, which allows MCCA-enabled nodes to enjoy collision-free and guaranteed channel access during reserved periods by means of prioritized and preemptive access mechanisms. Finally, we evaluate the performance of eMCCA through extensive simulations under different network scenarios. The simulation results indicate that eMCCA outperforms other mechanisms in terms of success rate, network throughput, end-to-end delay, packet-loss rate, and mesh coordinated channel access opportunity-utilization.
Adsorption capability of activated carbon synthesized from coconut shell
Md Shariful Islam,Bee Chin Ang,Samira Gharehkhani,Amalina Binti Muhammad Afifi 한국탄소학회 2016 Carbon Letters Vol.20 No.-
Activated carbon was synthesized from coconut shells. The Brunauer, Emmett and Teller surface area of the synthesized activated carbon was found to be 1640 m2/g with a pore volume of 1.032 cm3/g. The average pore diameter of the activated carbon was found to be 2.52 nm. By applying the size-strain plot method to the X-ray diffraction data, the crystallite size and the crystal strain was determined to be 42.46 nm and 0.000489897, respectively, which indicate a perfect crystallite structure. The field emission scanning electron microscopy image showed the presence of well-developed pores on the surface of the activated carbon. The presence of important functional groups was shown by the Fourier transform infrared spectroscopy spectrum. The adsorption of methyl orange onto the activated carbon reached 100% after 12 min. Kinetic analysis indicated that the adsorption of methyl orange solution by the activated carbon followed a pseudo-second-order kinetic mechanism (R2 > 0.995). Therefore, the results show that the produced activated carbon can be used as a proper adsorbent for dye containing effluents.
Comparative Analysis of Wind Power Energy Potential at Two Coastal Locations in Bangladesh
Asif Islam,Mohammad Mahmudur Rahman,Mohammad Shariful Islam,Satya Sundar Bhattacharya,김기현 한국대기환경학회 2015 Asian Journal of Atmospheric Environment (AJAE) Vol.9 No.4
In this study, wind conditions and its energy potential have been assessed by conducting a Weibull analysis of the wind speed data (over the period of 2002-2011) measured from a port city (Mongla) and an isolated island (Sandwip) in Bangladesh. The monthly mean wind speed at Mongla ranged from 1.60 m/s (December) to 2.47 m/s (April). The monthly values of Weibull shape parameter (k) were from 1.27 to 2.53. In addition, the values of the scale parameter (c) and the monthly wind power density ranged from 1.76 to 2.79 m/s and 3.95 to 17.45 W/ m2, respectively. The seasonal mean wind speed data varied from 1.72 (fall) to 2.29 m/s (spring) with the wind power density from 5.33 (fall) to 14.26 W/ m2 (spring). In the case of Sandwip, the results were comparable to those of Mongla, but moderate reductions in all the comparable variables were observed. The wind data results of these two areas have been compared with those of eight other locations in the world with respect to wind power generation scale. According to this comparison, the wind power generation scale for Mongla and Sandwip was adequate for stand-alone small/micro-scale applications such as local household consumption, solar-wind hybrid irrigation pumps, and battery charging.
The Effect of Financial Development, Tariff, and RTA on Exports: A Structural Gravity Analysis
Syed Nazrul Islam,Md. Shariful Islam,Md. Rayhanul Islam,Md. Ashraful Alam 세종대학교 경제통합연구소 2024 Journal of Economic Integration Vol.39 No.1
This paper examines the effect of financial development (FD), tariffs, and RTA on bilateral exports in a structural gravity framework. Applying high-dimensional fixed effects in OLS and PPML estimation technique in a panel framework covering 169 countries over 2001-2017, this paper finds that FD of both exporters and importers are an important determinant for boosting exports. The EIA has the most trade creation effect than any other form of RTA. Importers' FD has a larger effect on bilateral exports for developed to developed and developed and developing country trade than that of the exporters. The trade between developing to developing countries is positively affected by both exporters' and importers' FD; and negatively to a larger extent by tariff measures. However, in the case of developing and developed country estimation, FD of the exporter country is significantly affecting bilateral trade. Tariffs significantly distort trade, largely between developing and developed countries.