Joint access-backhaul perspective on mobility management in 5G networks

© 2017 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 ongoing efforts in the research, development and standardization of 5G, by both industry and academia, have resulted in the identification of enablers (Software Defined Networks, Network Function Virtualization, Distributed Mobility Management, etc.) and critical areas (Mobility management, Interference management, Joint access-backhaul mechanisms, etc.) that will help achieve the 5G objectives. During these efforts, it has also been identified that the 5G networks, due to their high degree of heterogeneity, high QoS demand and the inevitable density (both in terms of access points and users), will need to have efficient joint backhaul and access mechanisms as well as enhanced mobility management mechanisms in order to be effective, efficient and ubiquitous. Therefore, in this paper, we first provide a discussion on the evolution of the backhaul scenario, and the necessity for joint access and backhaul optimization. Subsequently, and since mobility management mechanisms can entail the availability, reliability and heterogeneity of the future backhaul/fronthaul networks as parameters in determining the most optimal solution for a given context, a study with regards to the effect of future backhaul/fronthaul scenarios on the design and implementation of mobility management solutions in 5G networks has been performed.Postprint (author's final draft

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

COMBINED EFFECT OF ORGANIC AND INORGANIC FERTILIZERS ON THE GROWTH AND YIELD OF MUNGBEAN

A Thesis Submitted to the Department of Soil Science Sher-e-Bangla Agricultural University, Dhaka in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE SOIL SCIENCE Semester:July-December, 2014An experiment was conducted at the experimental field of the farm of Sher-e-Bangla Agricultural University during the period from February to April -1 and branches plant were found from the combination of 70% recommended dose of inorganic fertilizer and 1.2 ton poultry manure ha -1 which was statistically similar or closely followed by 50% recommended dose of inorganic fertilizer and 2 ton poultry manure ha -1 treatment. Maximum numbers of pods plant -1 , seeds pod -1 and seed yield plant -1 were recorded in 70% recommended dose of inorganic fertilizer and 1.2 ton poultry manure ha -1 and it was closely followed by 50% recommended dose of inorganic fertilizer and 2 ton poultry manure ha -1 . Highest seed yield plant -1 and 1000-seed weight was recorded in 70% recommended dose of inorganic fertilizer and 1.2 ton poultry manure ha -1 . It was observed that, for the above parameters; 70% recommended dose of inorganic fertilizer and 1.2 ton poultry manure ha showed better results. Lowest values for all of the growth and yield parameters obtained from the treatment using no fertilizer. Highest N and P contents in seed were recorded in 70% recommended dose of inorganic fertilizer and 1.2 ton poultry manure ha -1 and it was statistically similar with the application of 50% recommended dose of inorganic fertilizer and 2 ton poultry manure ha -1 . K content of mungbean seed was differed non-significantly due to the different combinations of organic and inorganic fertilizer doses. Although, the highest K content in seed was recorded in T treatment that is 70% recommended dose of inorganic fertilizer and 6 -1 -1 1.2 ton poultry manure ha -1 . Lowest N, P and K contents of mungbean seed were found from the treatment using no fertilizer (

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

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

Assessing User Satisfaction in E-Haj Systems: Insights from Bangladesh

This study examines how e-haj management systems in Bangladesh affect user satisfaction. Therefore, the authors presented the hypothesis using webQual 4.0 Model. Data was collected using a 5-point-lickert questionnaire. 347 valid data were collected from Dhaka city. SPSS 27 displayed descriptive statistics, and Smart PLS 3.3.3 was analysed for measurement and structural model. The study found the positive impact of the usability, information quality, and service information quality of e-hajj on users' satisfaction. Thus, e-government implementers can get benefits from the findings of the paper as they come to know what factors motivates individuals to use the government's e-haj management portal. This finding also suggested that government should focus on website’s easy to navigate option, updated information and 24/7 customer service. As a result, this tendency of the citizens towards e-government services will be increased day by day and motivated to accept these e-hajj system. This research will increase trust and improve the democratic process for all citizens including businesses, or different government agencies by enhancing service quality provided to them. Small sample size, data collection period, and location are the limitations of this study. Future researchers may combine more model’s items and reduce these limitations to improve practical application studies

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