Teacher Education for University Teachers: Bangladesh Perspective

In this age of globalization every nation is struggling to keep pace with the upcoming demands to maintain quality. The progress of a nation largely depends on its citizens who are the products of its education system. This study is an attempt to unfold the status of university teachers of Bangladesh. Data collected through document review and in-depth interview of the university teachers that was analysed qualitatively. Researchers found that, most of the countries assiduously work for reshaping their teacher education while Bangladesh is focusing on needs for university teachers. However, most of the teachers express their opinion regarding emergence of teacher education and they agree that a good student might not be a good teacher always unless and until quality teacher education is there

Topas based high birefringent and low loss single mode hybrid-core porous fiber for broadband application

We present a through numerical analysis of a low loss and highly birefringent hybrid porous core with octagonal cladding structure for terahertz (THz) wave guidance. The proposed photonic crystal fiber (PCF) offers simultaneously low effective material loss (EML) as well as high birefringence in the frequency range of 0.8-1.05 THz with single mode operation. To attain high birefringence we introduce asymmetry in the core using both elliptical and circular air holes (hybrid). The numerical results obtained from the finite element method (FEM) which confirms low EML of 0.044 cm–1 as well as a high birefringence of ~0.043 at 0.73 THz operating frequency. Therefore, the fiber is likely to be useful in different THz polarization maintaining applications

Low loss topas based porous core single mode photonic crystal fiber for THz communications

In this paper, an extremely low loss hybrid hexagonal porous core and octagonally structured circular cladding photonic crystal fiber (PCF) for low loss terahertz (THz) wave propagation has been designed and proposed.  We have analyzed ultralow effective material loss (EML), high core power fraction and ultra-flattened dispersion in our proposed design. To investigate the transmission characteristics, perfectly matched layer (PML) is used in the outer boundary of the PCF. At an operating frequency of 1 THz, this design exhibits a low effective material loss of 0.045 cm-1 at a high core power fraction of 58.2% with 88% porosity. The proposed PCF shows dispersion variation of 0.225 ps/THz/cm. Also, this designed PCF can operate in single-mode condition successfully. It is anticipated that designed PCF can be employed in applications such as fiber optics communications, sensing and spectroscopy

Family planning knowledge and current use of contraception among the Mru indigenous women in Bangladesh: a multivariate analysis

Background: This article aims to understand the family planning (FP) knowledge and current use of contraception and its predictors among women of the Mru people -the most underprivileged indigenous community in Bangladesh. Methods: In this study, 374 currently married Mru women were interviewed and selected purposively from three upazilas (administrative subdistricts) of the Bandarban area, where most of the Mru people live. The association between the variables was assessed in bivariate analysis using the Chi-square test and binary logistic regression models were employed to explore the predictors of FP knowledge and current use of contraception among the Mru women. Results: Only about 40% of respondents had ever heard FP messages or about FP methods -two-fifths of the nationa

Cooperative spectrum sharing in 5G access and backhaul networks

© 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes,creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.Stringent demands for a continuous evolution of cellular networks push today academic and industrial researchers to re-think backhaul solutions for 5G. In one hand, wireless backhaul solutions are cost effective and easy to deploy but suffer from limited capacity. On the other hand, wired solutions have the potential to meet bandwidth requirements but usually involve higher costs. Thus, adoption of heterogeneous technologies will be necessary. Moreover, in 5G, access and backhaul networks will work closely, and therefore, total separation of their resources may not be possible anymore; rather, cooperation between the two portions of the cellular network is desirable. Subsequently, cooperative access-backhaul mechanisms become necessary to ensure the best use of the scarce resources, i.e. bandwidth. Hence, in this paper we present the idea of spectrum sharing among different links from a cooperative access-backhaul mechanism point of view. We present simulation results for different approaches of such sharing from a common spectrum pool. The results show that traffic-aware approaches show increased fairness thus reinforcing the idea of cooperative access-backhaul mechanisms as essential strategies in current and future networks.Postprint (published version

Cost analysis of 5G fronthaul networks through functional splits at the PHY layer in a capacity and cost limited scenario

© 2021 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes,creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.The expected growth in carried traffic and the added complexity of different deployment approaches (distributed vs. centralized), showing different requirements, make transport network one of the main design challenges in 5G. One of those challenges is posed by the Centralized Radio Access Network (CRAN) paradigm, whereby different functionalities of the base station are split between a central unit and a remote unit, both connected by a fronthaul/midhaul network. When this centralization includes physical layer functions, stringent capacity and delay constraints are imposed on the fronthaul, thus making its design and deployment more challenging and costly. At this point, the anticipated capacity requirements for fronthaul links are enormous and, as of today, no single technology can support such requirements. Hence, the complex transport network will be heterogeneous in nature. There is consensus in following two approaches to tackle the fronthaul challenge: i) building a heterogeneous network by combining different technologies; and ii) employing different functional splits, which have the potential to reduce the capacity requirements on fronthaul links. Hence, it is important that we exploit different potential technologies and a functional split approach for 5G fronthaul networks design. As our contribution, we show how intelligently selected functional splits at physical layer can be utilized to serve the radio access networks in a capacity-limited scenario. From a different point of view, we also propose maximizing the centralization by means of a heterogeneous combination of functional splits in a budget-limited scenario. Results presented in this paper show that the combination of functional splits has the potential to enable the design of heterogeneous fronthaul networks combining wireless and wired links, and reducing drastically both the required capacity (to 40%) and the total cost of ownership (to 35%).This work was supported in part by the EU Horizon 2020 Research and Innovation Program (5GAuRA) under Grant 675806, and in part by the Secretaria d’Universitats i Recerca del Departament d’Empresa i Coneixement from the Generalitat de Catalunya under Grant 2017 SGR 376.Peer ReviewedPostprint (published version

Dynamic spectrum allocation following machine learning-based traffic predictions in 5G

© 2021 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes,creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.The popularity of mobile broadband connectivity continues to grow and thus, the future wireless networks are expected to serve a very large number of users demanding a huge capacity. Employing larger spectral bandwidth and installing more access points to enhance the capacity is not enough to tackle the stated challenge due to related costs and the interference issues involved. In this way, frequency resources are becoming one of the most valuable assets, which require proper utilization and fair distribution. Traditional frequency resource management strategies are often based on static approaches, and are agnostic to the instantaneous demand of the network. These static approaches tend to cause congestion in a few cells, whereas at the same time, might waste those precious resources on others. Therefore, such static approaches are not efficient enough to deal with the capacity challenge of the future network. Thus, in this paper we present a dynamic access-aware bandwidth allocation approach, which follows the dynamic traffic requirements of each cell and allocates the required bandwidth accordingly from a common spectrum pool, which gathers the entire system bandwidth. We perform the evaluation of our proposal by means of real network traffic traces. Evaluation results presented in this paper depict the performance gain of the proposed dynamic access-aware approach compared to two different traditional approaches in terms of utilization and served traffic. Moreover, to acquire knowledge about access network requirement, we present a machine learning-based approach, which predicts the state of the network, and is utilized to manage the available spectrum accordingly. Our comparative results show that, in terms of spectrum allocation accuracy and utilization efficiency, a well designed machine learning-based bandwidth allocation mechanism not only outperforms common static approaches, but even achieves the performance (with a relative error close to 0.04) of an ideal dynamic system with perfect knowledge of future traffic requirements.This work was supported in part by the EU Horizon 2020 Research and Innovation Program (5GAuRA) under Grant 675806, and in part by the Secretaria d’Universitats i Recerca del Departament d’Empresa i Coneixement from the Generalitat de Catalunya under Grant 2017 SGR 376.Peer ReviewedPostprint (published version

Access-aware backhaul optimization in 5G

The final publication is available at ACM via http://dx.doi.org/10.1145/3265863.3265881Aggressive demand of future access network services is being translated into the stringent requirement on future backhaul infrastructure. It is not possible to take the backhaul resources for granted anymore; rather, more focused research is required to tackle the challenge of limited resources. It is also anticipated that, to meet the expectation of 5G, access and backhaul networks will work closely and therefore, total separation of their resources may not be possible anymore and joint operation is required. In this paper, we argue that, joint access-backhaul mechanisms is becoming necessary to ensure the best use of the scarce resources. We introduce the problem of statically assigning resources to capacity-limited backhaul links and we provide preliminary results to show the potential benefits of an intelligent access-aware backhaul capacity optimization scheme, where a central controller optimizes backhaul capacity according to corresponding access network requirements. Simulation results show that, with this approach, we are able to carry more traffic in a network limited by its backhaul capacity.Peer ReviewedPostprint (published version

Optimization of 5G fronthaul based on functional splitting at PHY layer

© 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes,creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works5G is coming with a promise to provide ubiquitous coverage with high data rate availability. To do so, densification of access points to enhance the system capacity is anticipated. For managing such densely populated network, 5G will be employing Centralized Radio Access Network (CRAN), where most of the Radio Access Network (RAN) functionalities are centralized in a central processing unit. This centralization reduces operational costs and eases implementation of advanced technologies, such as, Cooperative multipoint (CoMP) and enhanced inter-cell interference coordination (eICIC), in a cost efficient way. However, CRAN imposes stringent requirements on the fronthaul, i.e. the link connecting access points to the central unit, in terms of capacity and latency. Furthermore, future fronthaul networks are expected to rely on wireless technologies, since wired options are costly, not scalable and not always suitable for all scenarios. Therefore, meeting the expected requirements of fronthaul network utilizing capacity-limited wireless technologies may become an inescapable bottleneck. In this paper, we study different functional splits at the PHY layer in terms of data rate requirements and operational cost, and discuss the combination of different splits aimed at minimizing the overall cost and maximizing the centralization gains, while keeping the capacity requirements below the limit of the fronthaul.Peer ReviewedPostprint (published version

Awareness, treatment, and control of diabetes in Bangladesh : Evidence from the Bangladesh Demographic and Health Survey 2017/18

Background. The prevalence of diabetes is increasing in Bangladesh from ∼5% in 2001 to ∼13% in 2017/18 (∼8.4 million cases). The prevalence of undiagnosed diabetes was also found to be higher at 6% in 2017/18. However, very little is known about the management of diabetes assessed by diabetes awareness, treatment, and control. We aimed to estimate the age-standardised prevalence of awareness, treatment, and control of diabetes and its associated factors. Methods. Cross-sectional data from 1,174 Bangladeshi adults aged 18 years and older available from the most recent nationally representative Bangladesh Demographic and Health Survey (BDHS) 2017–18 were analysed. Outcomes were age-standardised prevalence of awareness, treatment, and control of diabetes, estimated using the direct standardisation. Multilevel mixed-effects Poisson regression models were used to identify factors associated with awareness, treatment, and control of diabetes. Results. Of the respondents we analysed, 30.9% (95% CI, 28.2–33.6) were aware that they had the condition, and 28.2% (95% CI, 25.6–30.7) were receiving treatment. Among those treated for diabetes, 26.5% (95% CI, 19.5–33.5) had controlled diabetes. The prevalence of diabetes awareness, treatment, and control was lower in men than women. Factors positively associated with awareness and treatment were increasing age and hypertension, while factors negatively associated with awareness and treatment were being men and lower education. Factors associated with poor control were secondary education and residing in Rajshahi and Rangpur divisions. Conclusions. This study provides evidence of poor management of diabetes in Bangladesh, especially in men. Less than one-third of the people with diabetes were aware of their condition. Just over one-fourth of the people with diabetes were on treatment, and among those who were treated only one-fourth had controlled diabetes. Interventions targeting younger people, in particular men and those with lower education, are urgently needed. Government policies that address structural factors including the cost of diabetes care and that strengthen diabetes management programmes within primary healthcare in Bangladesh are urgently needed