http://lib.buet.ac.bd;localhosthttp://:8080/xmlui/handle/123456789/1425 Institute of Appropriate Technology (IAT) 2026-04-21T13:33:26Z http://lib.buet.ac.bd;localhosthttp://:8080/xmlui/handle/123456789/7195 Development and characterization of a composite as an alternative of plastic foam by using waste paper and natural Jute Fiber Bhuiyan, Dr. Iftekhar Uddin; Kamruzzaman Rasel, Md.; 0419292005; 668.9/KAM/2024 It is well known to all that the population of the Earth is growing daily. To fulfill the needs, different types of plastic products are being used throughout the world, made from polymeric materials such as expanded polystyrene (EPS), expanded polypropylene (EPP), and Styrofoam (plastic foam) because of their easy processing, high durability, and many other properties. Packaging is one of the major sectors of polymeric material use. Packaging is the process by which goods or products are enclosed to protect products during distribution, storage, sale, and use. Of those polymeric materials, some are recyclable, but recycling is very costly; some are non-recyclable (melamine-thermosetting polymer). After use, most of the plastics are thrown into the environment, and those are getting mixed with land, wildlife, forests, and aquatic ecosystems, creating a threat to the everyday lives of people, wildlife, marine animals, and so on. Since polymeric materials have a long lifetime and a long time required to decompose naturally, researchers are continuously trying to develop alternative products that can be used as a substitute for plastic products. Researchers have used natural fiber-based products, but most of them are based on polymers, where those polymers act as a matrix form of a composite, such as epoxy resin, polyester, polypropylene, HDPE, LDPE, Vinyl ester resin, epoxy, and polyester resin and natural fiber used as a reinforcing agent. Most of them are non-biodegradable and take a long time to decompose naturally. There is an opportunity to use natural-based materials in matrix form. Hence, this research aims to develop a composite by using waste papers as a matrix material of the composite and jute fiber as the reinforcing agent that can reduce the use of certain portions of plastic-type products, especially Styrofoam in the packaging sector. The hand lay-up method was used to fabricate the composite after collecting the raw materials, and starch (arrowroot powder) was used as a binder. After the final curing of the developed composite, shore hardness test, stress test, strain test, compressive test, density test, water absorption test, and degradation test were done and compared with the available Styrofoam sample. The experimental results indicate that developed composite samples are superior in terms of hardness and compressive strength compared to available Styrofoam samples, developed composite samples are inferior in terms of density and water absorption compared to the available Styrofoam samples. The level of strain found in both samples (Developed and available samples) is comparable. Also, the degradation test indicates that developed composite samples are degradable in soil and water, whereas available Styrofoam samples are known to be non-biodegradable. Typically, a portion of the waste paper produced is recycled to decrease reliance on virgin raw materials and to lessen the use of natural resources like trees, water, and other components. However, there is a lack of effective management aimed at minimizing waste paper generation at its source. This research can contribute to addressing this issue by illustrating methods to reduce waste paper generation and ultimately utilizing existing technology to recycle the paper waste created. 2024-09-03T00:00:00Z http://lib.buet.ac.bd;localhosthttp://:8080/xmlui/handle/123456789/6977 Development and evaluation of construction and demolition waste management framework in the context of Dhaka city Bhuiyan, Dr. Iftekhar Uddin; Sabbir Ahammed Rayhan, Dewan; 0419292002; 628.540954922/SAB/2024 This thesis looks over the current Construction and Demolition Waste Management (C&DWM) situations by scrutinizing the definition, classification, components, compositions, the generated sources and causes, the global scenario, impacts of generated Construction and Demolition Wastes (C&DWs), waste management hierarchy (WMH), 3R Principles, Circular Economy (CE), tools and frameworks of C&DWM. Dhaka city is witnessing rapid infrastructural development. Now, C&DW generation is becoming a burning issue due to its adverse impacts. This study reviews the present scenario of Dhaka city regarding the status of C&DW generation, approaches for minimizing C&DW generation, existing systems for managing C&DWs, existing relevant strategies, acts, and policies for C&DWM, and previous research on C&DWM. The review finds that landfilling, on-site and off-site disposal, and disposal in unauthorized places are the common strategies of C&DWM in Dhaka city that result in environmental pollution in the city as well as lessening the potential land spaces in the city. Moreover, the old landfill sites in Dhaka city are reaching their fullest capacity. The main objective of this study is to introduce a sustainable C&DWM framework for evaluating the C&DWM alternatives in Dhaka city by incorporating the application of expanded Waste Management Hierarchy (E-WMH) and Multi-criteria Decision Analysis (MCDA) models because these tools don’t get considerable attention in the C&DWM field of Bangladesh. This study considers the E-WMH principles as the alternatives for managing C&DWs in Dhaka city and selects and groups the criteria into social, economic, environmental, and technical criteria to achieve sustainability based on the comprehensive literature review and the Delphi survey with the subject-matter experts in Bangladesh. The ELECTRE I and ELECTRE II MCDA methods are employed in this study because these methods are suitable for solving environmental-related problems. Based on the results of ELECTRE I and ELECTRE II methods, reuse, recovery, and prevent are the suitable strategies, and incineration (burn), and treat and disposal are the poorest strategies for managing C&DWs in Dhaka city. Finally, this thesis provides some recommendations for C&DWM in Dhaka City to achieve greater efficiency in C&DWM and pinpoint some directions of the scope of future research in the field of C&DWM. 2024-05-11T00:00:00Z http://lib.buet.ac.bd;localhosthttp://:8080/xmlui/handle/123456789/6927 Behavioral pattern analysis of solar energy users of Bangladesh and proposal of an incentive regulation model to achieve energy sufficiency Ahmad, Farid; Abul Ulayee, Hasan al Bashar; 1014292014; 621.47095492/HAS/2021 In the era of 4th Industrial revolution, energy is a pre-condition for the development of an energy-deficit country like Bangladesh. Bangladesh ranks low with regard to global competitiveness in the context of reliable electricity supply and transparent tariffs. Bangladesh government has already taken a policy decision to arrange 10 percent of total energy from renewable sources whereasonly 3.02% of the target is achieved.Around 5 million Solar Home System (SHS) havealready been installed in Bangladesh to reach the target.A behavioral pattern analysis of these users can find substantial and influential factors which are determinate rationales behind using solar energy. The objective of the research was to find out the solar energy users’usage pattern and factors influencing the pattern. Another core objective of this research was to develop an Incentive Regulation Model based on ‘Solar Energy Data Bank with Virtual Grid Concept’ by analyzing the usage pattern and to test the Incentive Regulation Model. The method used in this research was a qualitative approach with quantitative analysis of the survey data. The methodology included survey in the Solar Home System users with appropriate questionnaire and data analysis and pattern recognition on the received data. The Incentive Regulation Model was developed based on the data and considering the rational expectation of the users. The outcome of this research was the usage pattern of Bangladeshi Solar Energy users and what were the influencing factors that enable them to use solar energy. Based on the survey, an Incentive Regulation Model was also proposed with a new concept of offline virtual grid. As the Model was a proposed one, to justify it WEKA open source data mining software was used whether the incentive helps to grow the number of solar energy users or not. Finally, some policy decisions were derived from the incentive model taking incentive levels, location factors, program design, and monitoring and evaluation strategies for sustainable energy management into account 2021-09-25T00:00:00Z http://lib.buet.ac.bd;localhosthttp://:8080/xmlui/handle/123456789/6902 A machine learning based integrated framework for e-commerce management through customized customer retention strategy Sanam, Dr.Tahsina Farah; Ishrat Jahan; 0419292009; 658.802/ISH/2024 Ine-commerce,itismorecost-effectivetoretainexistingcustomersthantoattractnewones. Therefore, churn control is crucial in managing attrition. This study aims to ad-dressagapintheliteraturebycombiningchurnprediction,customersegmentation,andrecommendationstoprovideacomprehensiveplatformforcustomizedcustomerretentionstrategy.Theframeworkconsistsofthesethreecomponents.ExperimentalanalysisforcustomerchurnpredictionshowsthatCatBoostperformsthebestinthedatasetwith100%accuracyand100%F1-score.Afterselectingthebestclassifier,recursivefeatureelimination (RFE) is applied to find the rank of features for the next step. This paperfills a research gap and contributes to the existing literature in developing a customerretentionmethod. After implementing churn prediction, the cluster tendency test is performed, and theHopkins score is 0.09322634776929459. This score indicates that the dataset is appropriateforclustering.TheCalinski-HarabaszindexofK-meansishigherthanHierarchical Clustering.Comparing k-means, hierarchical clustering, and DBSCAN, k-meansgives the best performance.The resulting cluster profiles are used for personalizedrecommendations. Collaborative filtering coverage is larger than popularity-based recommendations.The root mean square errors (RMSE), mean absolute errors (MAE),and mean square errors (RMSE) are used for comparing criteria. The SVD model hasRMSE 1.26, MAE 0.99, and MSE 1.69. The test time of SVD is 0.00143, which is thelowest.Precisionis89%andrecallis99.80%whichmeansthat89%oftherecommendations apply to users. Our proposed study shows that with this integrated framework,wehaveachievedsignificantimprovement.Ourstudyhasgiventhebestresultineveryphase of the framework. So, integrating product recommendation with customer churnpredictionsandcustomersegmentationwillenablepersonalizedexperiences,proactivecustomer engagement, maximization of customer lifetime value, data-driven decision-making, and a competitive edge in the market in the context of our country.It willalsoprovideastrongandefficientcustomerretentionstrategytomakee-commercefeelsuccessfulinourcountry.Finally,thisresearchinvestigatesthekeysustainabilityindicatorsforintegratingMLine-commercecustomizedcustomerretentionandconductsasystematicassessmenttoprioritizetheindicatorsbasedontheperspectivesofpertinentexperts in the context of Bangladeshi e-business to assess the long-term sustainabilityoftheproposedsystem. 2024-01-29T00:00:00Z