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To materialize the inherent opportunities of incoming sediment load, various interventions are being practiced for sediment management in rivers and delta systems. Broadly, the practiced methods can be divided into two categories: (i) management for accelerating siltation to enhance land reclamation and counterbalancing bank erosion (ii) management for de-siltation in the channels to maintain required navigational flow depth. The pre-requisites to achieve the above targets, simultaneously, are quite contradictory as land reclamation need more sediment, while less sediment load is necessary for the maintaining the navigational depth. To overcome the above constraints, Bandal-like Structures (BLS), the indigenous nature-based solution, has conceptualized to utilize through redistributing the local flow-sediment regime to create a sediment deficit zone within the river side and a sediment surplus zone along the bankside that can eventually, be useful for the maintenance of navigational channels and bank stabilization, simultaneously. In this article, the experiences of BLS, to achieve both functions simultaneously are discussed based on the research experiences for last 20 years. Out of many implemented BLS at different scales in the Ganges-Jamuna-Brahmaputra (GBM) system, a well-documented case study of its application is showcased along a reach of the braided Jamuna River. Based on the evaluation of the performance of the implemented case study coupled with the existing indigenous knowledge, a hybrid approach integrating the conventional and community sciences, is proposed as a nature-based solution for sustainable sediment management in the river systems of Bangladesh.

One of the critical design problems in Wireless Sensor Networks (WSNs) is the Relay Node Placement (RNP) problem. Inefficient deployment of RNs would have adverse effects on the overall performance and energy efficiency of WSNs. The RNP problem is a typical example of an NP-hard optimization problem which can be addressed using metaheuristics with multi-objective formulation. In this paper, we aimed to provide an efficient optimization approach considering the unconstrained deployment of energy-harvesting RNs into a pre-established stationary WSN. The optimization was carried out for three different objectives: energy consumption, network coverage, and deployment cost. This was approached using a novel optimization approach based on the integration of the Particle Swarm Optimization (PSO) algorithm and a greedy technique. In the optimization process, the greedy algorithm is an essential component to provide effective guidance during PSO convergence. It supports the PSO algorithm with the required information to efficiently alleviate the complexity of the PSO search space and locate RNs in the spots of critical significance. The evaluation of the proposed greedy-based PSO algorithm was carried out with different WSN scenarios of varying complexity levels. A comparison was established with two PSO variants: the classical PSO and a PSO hybridized with the pattern search optimizer. The experimental results demonstrated the significance of the greedy algorithm in enhancing the optimization process for all the considered PSO variants. The results also showed how the solution quality and time efficiency were considerably improved by the proposed optimization approach. Such improvements were achieved using a simple integration technique without adding to the complexity of the system and introducing additional optimization stages. This was more evident in the RNP scenarios of considerably large search spaces, even with highly complex and challenging setups.

Today, contemporary ceramic sculpture expressions come in various forms. Ceramic sculpture is also a medium to express ideas and creative imagination for ceramic artists. This research paper presents a comparative discussion of Contemporary Ceramic Sculptures between China and Bangladesh, which aims to promote the further development of ceramic sculpture through exchanges of ceramic culture. This research not only analyzes contemporary ceramic sculptures between China and Bangladesh but also learns about the economic, cultural, and social influences of the two countries for the development of global ceramic sculptures. Two countries review the history of ceramics and talk about the specificities in the field of ceramics. This study aims to reveal the development of ceramic sculptures between the two countries so that this research can find out how contemporary ceramic artists in China and Bangladesh created unique and themed ceramics. How modern ceramic sculpture influence by philosophy, culture, tradition, and material effect. The combination of modern china and Bangladeshi ceramic sculpture is so touching and unique. The conclusion of this research is through various experiments and creative learning of ceramic sculptors, making the structure of knowledge of modern ceramic artists become formed. As a result, artistic concepts have become more diverse, and the two countries, Bangladesh and China, can exchange ideas in the creation of ceramic sculptures.

In this article, we report a physics-based compact model of drain current for InAs-on-insulator MOSFETs. The quantum confinement effect has been incorporated in the proposed model by solving the 1-D Schrodinger–Poisson equations without using any empirical model parameter. The model accurately captures the variation of surface potential, charge density in the inversion layer, and subband energy levels with gate bias inside the quantum well. The conduction-band nonparabolicity effect on modification in eigenenergy, effective mass, and density of states is derived and incorporated into the proposed model. The velocity overshoot effect that originates from the quasi-ballistic nature of carrier transport is also considered in the model. The proposed drain current model has been implemented in Verilog-A to use in the SPICE environment. The model predicted results are in good agreement with the commercial device simulator results and experimental data.

A moving water mass generates force which is exerted on its moving path. Cyclone generated storm surge or earthquake generated tsunami are specific examples of moving water mass the generates force along the coasts. In addition to human lives, these moving water masses cause severe damages to the coastal infrastructure due to tremendous force exerted on these structures. To assess the damage on these infrastructures, an essential parameter is the resultant force exerted on these structures. To evaluate the damages, there is hardly any quantitative method available to compute this force. In this paper we have developed a semi-analytical model, named as Dynamic Force Model (DFM), by using Variational Iteration Method to compute this force. As governing equations, we have used the Saint Venant equations which are basically 1D shallow water equations derived from the Navier-Stokes equations. The verified, calibrated and validated DFM is applied in Bangladesh coastal zone to compute dynamic thrust force due to tropical cyclone SIDR.

This paper describes a polynomial time algorithm for solving graph isomorphism and automorphism. We introduce a new tree data structure called Walk Length Tree. We show that such tree can be both constructed and compared with another in polynomial time. We prove that graph isomorphism and automorphism can be solved in polynomial time using Walk Length Trees.

Deltas occupy only 1% of global land surface area, but contain 7% of the global human population (ca. 500 million). The influence of changing and interacting climates, demography, economy, land use and coastal/catchment management on deltaic social-ecological systems is complex and little understood. We apply a new and innovative integrated assessment model: The Delta Dynamic Integrated Emulator Model (ΔDIEM) to coastal Bangladesh to explore a range of plausible future scenarios and quantify the sensitivities of selected environmental and socio-economic outcomes to key external and internal drivers. ΔDIEM is a tightly coupled integrated assessment platform considering climate and environmental change, demographic changes, economic changes, household decision making and governance, and designed to support the delta planning in Bangladesh. ΔDIEM allows the testing of a large number of water-based structural and policy interventions within a robust scenario framework, as well as quantify different development trajectories and their trade-offs. In this sensitivity analysis, we quantified the impact of (i) climate (precipitation, temperature and runoff), (ii) relative sea-level rise, (iii) cyclone frequency, (iv) embankment maintenance, (v) population size, (vi) economic changes at household level such as selling price of crops, cost of food, etc., (vii) land cover, and (viii) farming practices on trajectories of inundated area, soil salinity, rice productivity, poverty, income inequality and GDP/capita, assuming two contrasting scenarios in a more Positive and a more Negative World. Trajectories of these plausible futures showed a clear separation and the long-term trends are greatly influenced by the combinations of scenario assumptions. Our systemic results indicate a diverse potential set of futures for coastal Bangladesh, where good governance and adaptation could effectively mitigate the threat of sea-level rise-induced catastrophic inundation and other adverse impacts of the changing climate. However, societal inequality requires special attention otherwise climate-sensitive population groups may be left behind.

Climate-induced hazard is a global problem, which may disproportionately affect those living in riverine and coastal chars in the Ganges–Brahmaputra–Meghna (GBM) delta of Bangladesh, where people’s lives and livelihoods are largely dependent on nearby water bodies. By way of a two-dimensional hydrodynamic simulation, effect of climate change has been assessed for riverine and coastal chars in terms of flood disasters. Based on a medium–high carbon emission scenario A1B, which corresponds to the rise of temperature by 2.7° (mid-century) and by 4.85° (end-century) from the present day, with the associated sea-level rise, a total of 14 scenarios has been generated and investigated in fluvial, fluvio-tidal, and storm surge flooding conditions. This study indicates that despite having morphological characteristics similar to the ones in the general area, chars are likely to face different hazard conditions resulting from climatic variables. Significant changes in flood hazards are visualized within the end-century time horizon for both riverine and coastal chars. Coastal polders are likely to play a strategic role in reducing the impacts of climate change-induced hazards.

Quantified flood risk assessments focus on asset losses, neglecting longer-term impacts to household welfare via income and consumption losses. The extent of welfare losses depends upon resilience – the ability to anticipate, resist, cope, recover and learn from a shock. Here, we use a novel welfare loss modelling framework and perform a high-resolution spatial analysis in coastal Bangladesh to quantify welfare losses from a tropical cyclone under present and future climatic and socio-economic conditions. We further test various adaptation options that are intended to enhance resilience. Results show that poor households experience, on average, 7% of the asset losses, but 42% of the welfare losses. Combining dike heightening, post-disaster support and stronger housing can reduce welfare losses by up to 70%, and foster sustainable development by benefitting the poor, increasing resilience and demonstrating robustness under socio-economic and climatic uncertainties. Thus, a welfare-orientated perspective helps to identify adaptation options that enhance resilience and leave no-one behind.

Bangladesh is one of the most climate-sensitive countries globally, creating significant challenges for future development. Here we apply an integrated assessment model — Delta Dynamic Integrated Emulator Model (ΔDIEM) — to the south-west coastal zone of Bangladesh to explore the outcomes of four contrasting and plausible development trajectories under different climate and socio-economic scenarios: (1) embankment rehabilitation; (2) build elevation via controlled sedimentation; (3) planned migration (managed retreat) and (4) ‘do nothing’ (unplanned migration and abandonment). Embankment rehabilitation reduces flood risk, but at a high economic cost and enhancing waterlogging. Planned and unplanned migration combined with limited infrastructure management and governance both result in significant abandonment. Building elevation through sedimentation has the potential for increased environmental and economic sustainability but raises equity issues. Poverty and inequality persist across all scenarios, and outmigration from the coastal zone continues, although the magnitude is sensitive to assumptions about sea-level rise, socio-economic development and development trajectory. Integrated assessment tools linking the environment, people and policy choices, such as the ΔDIEM used here, highlight the complex interactions occurring in a dynamic delta environment. Such analysis supports informed management, development and adaptation.

Although ABO incompatible kidney transplantations are increasingly being practised worldwide, in Bangladesh it was never attempted. Here we report the first ever ABO incompatible kidney transplantation case performed in Bangladesh. The patient was a 23-year-old male with end-stage kidney disease secondary to chronic glomerulonephritis on haemodialysis. The only kidney donor available was his mother who had a different blood-group (patient O positive; mother A positive). His baseline anti-A IgG titre was 1:128. We used a modified desensitization protocol with low-dose Rituximab, triple immunosuppression (Tacrolimus, Mycophenolate Sodium and Prednisolone) and 3 sessions of plasmapheresis followed by IVIG. His Anti-A IgG titre was brought down to 1: 8 before transplantation. He also received basiliximab as induction therapy. He successfully underwent renal transplantation across the ABO barrier. After transplantation his IgG titre was monitored which was remained 1:4. At 1, 3 and 6 months of post transplant, serum creatinine level was 207 µmol/L, 182 µmol/L and 183 µmol/L, respectively. This was the first case of ABO-incompatible kidney transplantation in Bangladesh. This case gives us the confidence that more ABO-incompatible kidney transplantations can be performed in a resource limited setting and high infection risk countries like ours following a more cautious approach. This will substantially increase the living kidney donor pool; hence reduce the economic and health impact of continuing long term dialysis therapy in Bangladesh. Keywords: ABO incompatible kidney transplantation, Anti-A IgG titre, Desensitization, Plasmapheresis, End Stage Kidney Disease

There is growing recognition that new approaches, underpinned by more system-oriented decision support tools, will be required to facilitate development compatible with the Sustainable Development Goals (SDGs) and to prevent the risk of dangerous socio-environmental breakdown. We demonstrate the potential of Integrated Assessment Models (IAMs) to inform strategic policy decision making at a regional level, helping to understand key trade-offs as well as indirect or unintended impacts. The stakeholder co-produced Delta Dynamic Emulator Model (ΔDIEM) model is applied to the southwest coastal zone (pop. 14m) where high rates of extreme poverty prevail. The model integrates biophysical drivers, ecosystem services and community level household wellbeing, and in this work is applied an behalf of the Planning Commission of the Government of Bangladesh in order to assess strategic risk in coastal Bangladesh (2050) and particularly to support the Bangladesh Delta Plan 2100. The intervention we investigated included i) A proposed extensive polder network in the south-central region of coastal Bangladesh ii) Strategic development of a chronically waterlogged area of the delta. In both areas we highlight insights on implications of biophysical drivers on poverty, livelihoods and inequality as well as on risk transfer between regions and populations associated with implementation. In doing so we critically assess IAMs’ growing potential to ask and explore key questions and scenarios about the functioning of integrated biophysical and socioeconomic systems. Finally, we point to ongoing applications of the model in West Bengal

Water logging is the most acute problem inside the polders of the south-west coastal region of Bangladesh. Though polders were constructed in order to protect the region from tidal inundation, these polders are now believed to be responsible for creating water-logging issues. It is generally believed that polders cause skewed sedimentation in the rivers, which then results in rise in bed levels of the peripheral rivers when compared to land elevation inside the polders. This phenomenon slowed down the natural gravity drainage and as a result extensive water-logging was initiated. While trying to find the causes of water-logging inside polders, impacts of the internal drainage system was largely ignored. Unplanned road construction inside polders hindered the natural drainage route which resulted in delayed and obstructed drainage. This research aims to study the impacts of road network and the dredging of peripheral river on water-logging. It is found that the appropriate drainage route along with river excavation can reduce the extent of water-logging in the area. The strategic placement of culverts plays an important role in determining maximum drainage rate. River dredging is only effective if the internal drainage system is improved.

Outcome Based Education (OBE) is a well established method of teaching/learning in modern engineering education. Continual Quality Improvement (CQI) is at the heart of OBE system that ensures the curriculum, Course Outcomes (CO), Program Outcomes (PO) and Program Educational Objectives (PEO) are periodically updated so that the program is well aligned with the expectations from engineers in professional world. To implement such an effective and ever-updating system successfully, the importance of an automated outcomes evaluation method is undeniable. To this aim, an effective automated outcomes evaluation algorithm with different methods of calculating CO attainment is proposed in this paper. Since Microsoft (MS) Excel is the most commonly used platform for record keeping and grading, the proposed algorithm is implemented in MS Excel. The academics of the department of Electrical and Electronic Engineering (EEE), East West University (EWU) are currently using the beta version of the tool wherein the algorithm is implemented.

As the price of electricity from photovoltaic (PV) systems approach grid parity, there is an increased interest in experimentation and research in advanced PV systems to further reduce its cost. Limited space in PV experimental facilities, and large number of configurations to be tested have led to small scale experiments. The scaled down testbeds are prone to unwanted fluctuations of different variables which can affect the outcomes of an experiment. We present a technique where a single setup is automatically remorphed into different configurations with recording of data for each configuration in quick sequence. The data of all the configurations are therefore multiplexed in the data stream. By synchronizing the setup re-configuration with data acquisition, we can later de-multiplex the data to their corresponding configurations. This method can minimize variability such as effects of spurious light collection, panel to panel performance inconsistencies, day to day insolation changes, etc. to design more controlled experiments with accurate analysis.