109 research outputs found

    Prediction of Compressive Strengths of Concrete with Partial Fine Aggregate of Plastic Using Artificial Neural Network and Revisions

    Get PDF
    In recent past years, plastic waste has been a environmental menace. Utilization of plastic waste as fine aggregate substitution could reduce the demand and negative impacts of sand mining while addressing waste plastic challenges. This study aims at evaluating compressive strengths prediction models for concrete with plastic—mainly recycled plastic—as partial replacement or addition of fine aggregates, by use of artificial neural networks (ANNs), developed in OCTAVE 5.2.0 and datasets from reviews. 44 datasets from 8 different sources were used, that included four input variables namely:- water: binder ratio; control compressive strength (MPa); % plastic replacement or additive by weight and plastic type; and the output variable was the compressive strength of concrete with partial plastic aggregates. Various models were run and the selected model, with 14 nodes in hidden layer and 320,000 iterations, indicated overall root mean square error (RMSE) , absolute factor of variance (R2), mean absolute error (MAE) and mean absolute percentage error (MAPE) values of 1.786 MPa, 0.997, 1.329 MPa and 4.44 %. Both experimental and predicted values showed a generally increasing % reduction of compressive strengths with increasing % plastic fine aggregate. The model showed reasonably low errors, reasonable accuracy and good generalization. ANN model could be used extensively in modeling of green concrete, with partial waste plastic fine aggregate. The study recommend ANNs models application as possible alternative for green concrete trial mix design. Sustainable techniques such as low-cost superplasticizers from recycled material and cost-effective technologies to adequately sizing and shaping plastic for fine aggregate application should be encouraged, so as to enhance strength of concrete with partial plastic aggregates.En los últimos años, los desechos plásticos han sido una amenaza para el medio ambiente. La utilización de desechos plásticos como sustitución de agregados finos podría reducir la demanda y los impactos negativos de la extracción de arena al tiempo que aborda los desafíos de los desechos plásticos. Este estudio tiene como objetivo evaluar modelos de predicción de resistencias a la compresión para concreto con plástico, principalmente plástico reciclado, como reemplazo parcial o adición de agregados finos, mediante el uso de redes neuronales artificiales (ANN), desarrollado en OCTAVE 5.2.0 y conjuntos de datos de revisiones. Se utilizaron 44 conjuntos de datos de 8 fuentes diferentes, que incluían cuatro variables de entrada, a saber: - relación agua: aglutinante; controlar la resistencia a la compresión (MPa); % de reemplazo o aditivo de plástico por peso y tipo de plástico; y la variable de salida fue la resistencia a la compresión del hormigón con agregados plásticos parciales. Se ejecutaron varios modelos y el modelo seleccionado, con 14 nodos en la capa oculta y 320.000 iteraciones, indicó el error cuadrático medio general (RMSE), el factor de varianza absoluto (R2), el error absoluto medio (MAE) y el error porcentual absoluto medio (MAPE). ) valores de 1,786 MPa, 0,997, 1,329 MPa y 4,44%. Tanto los valores experimentales como los predichos mostraron un% de reducción generalmente creciente de las resistencias a la compresión con el aumento del% de agregado fino plástico. El modelo mostró errores razonablemente bajos, precisión razonable y buena generalización. El modelo ANN podría utilizarse ampliamente en el modelado de hormigón verde, con áridos finos de plástico de desecho parcial. El estudio recomienda la aplicación de modelos ANNs como posible alternativa para el diseño de mezclas de prueba de concreto verde. Deben fomentarse las técnicas sostenibles, como los superplastificantes de bajo costo a partir de material reciclado y las tecnologías rentables para dimensionar y dar forma adecuada al plástico para la aplicación de agregados finos, a fin de mejorar la resistencia del hormigón con agregados plásticos parciales

    Permodelan Nilai Slump Dan Determinasi Variabel Paling Berpengaruh Dengan Pendekatan Regresi

    Get PDF
    Perancangan campuran beton yang tepat harus sesuai struktur yang dibutuhkan, metode konstruksi dilapangan dan ekonomis. Proses pencarian komposisi dan proporsi campuran dilakukan dengan percobaan berulang-ulang. Hasil pencampuran di uji dengan tes slump dan kuat tekan. Pengujian dilakukan untuk memastikan kualitas beton sesuai dengan karakter beton yang dibutuhkan dalam konstruksi. Proses pencarian yang berulang- ulang membutuhkan waktu yang lama dan biaya material yang tidak sedikit. Kerugian lainnya adalah adanya residu berupa hasil pengujian yang berupa beton padat. Kerugian tersebut diminimalisir dengan perancangan permodelan proporsi campuran dengan merujuk nilai slump target. Kajian yang pernah dilakukan menggunakan metode nonlinear, akan tetapi pada kajian ini mencoba menggunakan metoda dasar regresi linear

    Appropriate Wisdom, Technology, and Management toward Environmental Sustainability for Development

    Get PDF
    The protection and maintenance of environmental resources for future generations require responsible interaction between humans and the environment in order to avoid wasting natural resources. According to an ancient Native American proverb, “We do not inherit the Earth from our ancestors; we borrow it from our children.” This indigenous wisdom has the potential to play a significant role in defining environmental sustainability. Recent technological advances could sustain humankind and allow for comfortable living. However, not all of these advancements have the potential to protect the environment for future generations. Developing societies and maintaining the sustainability of the ecosystem require appropriate wisdom, technology, and management collaboration. This book is a collection of 19 important articles (15 research articles, 3 review papers, and 1 editorial) that were published in the Special Issue of the journal Sustainability entitled “Appropriate Wisdom, Technology, and Management toward Environmental Sustainability for Development” during 2021-2022.addresses the policymakers and decision-makers who are willing to develop societies that practice environmental sustainability, by collecting the most recent contributions on the appropriate wisdom, technology, and management regarding the different aspects of a community that can retain environmental sustainability

    2023- The Twenty-seventh Annual Symposium of Student Scholars

    Get PDF
    The full program book from the Twenty-seventh Annual Symposium of Student Scholars, held on April 18-21, 2023. Includes abstracts from the presentations and posters.https://digitalcommons.kennesaw.edu/sssprograms/1027/thumbnail.jp

    International Conference on Mathematical Analysis and Applications in Science and Engineering – Book of Extended Abstracts

    Get PDF
    The present volume on Mathematical Analysis and Applications in Science and Engineering - Book of Extended Abstracts of the ICMASC’2022 collects the extended abstracts of the talks presented at the International Conference on Mathematical Analysis and Applications in Science and Engineering – ICMA2SC'22 that took place at the beautiful city of Porto, Portugal, in June 27th-June 29th 2022 (3 days). Its aim was to bring together researchers in every discipline of applied mathematics, science, engineering, industry, and technology, to discuss the development of new mathematical models, theories, and applications that contribute to the advancement of scientific knowledge and practice. Authors proposed research in topics including partial and ordinary differential equations, integer and fractional order equations, linear algebra, numerical analysis, operations research, discrete mathematics, optimization, control, probability, computational mathematics, amongst others. The conference was designed to maximize the involvement of all participants and will present the state-of- the-art research and the latest achievements.info:eu-repo/semantics/publishedVersio

    The Second Conference on Lunar Bases and Space Activities of the 21st Century, volume 2

    Get PDF
    These 92 papers comprise a peer-reviewed selection of presentations by authors from NASA, the Lunar and Planetary Institute (LPI), industry, and academia at the Second Conference on Lunar Bases and Space Activities of the 21st Century. These papers go into more technical depth than did those published from the first NASA-sponsored symposium on the topic, held in 1984. Session topics included the following: (1) design and operation of transportation systems to, in orbit around, and on the Moon; (2) lunar base site selection; (3) design, architecture, construction, and operation of lunar bases and human habitats; (4) lunar-based scientific research and experimentation in astronomy, exobiology, and lunar geology; (5) recovery and use of lunar resources; (6) environmental and human factors of and life support technology for human presence on the Moon; and (7) program management of human exploration of the Moon and space

    (RE)embodying biotechnology : towards the democratization of biotechnology through embodied art practices

    Get PDF
    Contemporary discourse surrounding biotechnology places great emphasis on digital metaphors in describing the biological sciences. In these discourses it is as if mankind's 'cumulative' technology - computation - performs the ultimate science, the dominion of man over nature through the application of numeric code to living organism. This general application of computational models to instances of biotechnology provides a sterilizing affect, removing all that is wet, bloody, unruly, and animal, from mass imaginations of the biotech future. As I argue this vision of biotechnology (as it is presented to non-specialists) may serve to nullify public engagement in the complex ethical dilemmas that arise from engaging in technologies of the body. (RE)embodying Biotechnology focuses. on reuniting notions of embodiment with the language, analysis, practice, and representation of contemporary biotechnologies. With a social and political mandate that advocates informed public discourse, (RE)embodying Biotechnology complicates, rather than simplify our understanding of the biotech field. Methodologically, I propose artistic means for non-specialists to engage in biotechnology as an embodied practice through the mobilization of a 'critical participatory methodology'. (RE)embodying Biotechnology is a research I creation thesis; comprised of the documentation of a body of work and a text that reflects on how artistic engagement in the biotechnological field may allow for non-specialists to engage critically with evolving biotechnologies

    Proceedings of the WABER 2017 Conference

    Get PDF
    The scientific information published in peer-reviewed outlets carries special status, and confers unique responsibilities on editors and authors. We must protect the integrity of the scientific process by publishing only manuscripts that have been properly peer-reviewed by scientific reviewers and confirmed by editors to be of sufficient quality. I confirm that all papers in the WABER 2017 Conference Proceedings have been through a peer review process involving initial screening of abstracts, review of full papers by at least two referees, reporting of comments to authors, revision of papers by authors, and reevaluation of re-submitted papers to ensure quality of content. It is the policy of the West Africa Built Environment Research (WABER) Conference that all papers must go through a systematic peer review process involving examination by at least two referees who are knowledgeable on the subject. A paper is only accepted for publication in the conference proceedings based on the recommendation of the reviewers and decision of the editors. The names and affiliation of members of the Scientific Committee & Review Panel for WABER 2017 Conference are published in the Conference Proceedings and on our website www.waberconference.com Papers in the WABER Conference Proceedings are published open access on the conference website www.waberconference.com to facilitate public access to the research papers and wider dissemination of the scientific knowledge

    Crab and cockle shells as heterogeneous catalysts in the production of biodiesel

    Get PDF
    In the present study, the waste crab and cockle shells were utilized as source of calcium oxide to transesterify palm olein into methyl esters (biodiesel). Characterization results revealed that the main component of the shells are calcium carbonate which transformed into calcium oxide upon activated above 700 °C for 2 h. Parametric studies have been investigated and optimal conditions were found to be catalyst amount, 5 wt.% and methanol/oil mass ratio, 0.5:1. The waste catalysts perform equally well as laboratory CaO, thus creating another low-cost catalyst source for producing biodiesel. Reusability results confirmed that the prepared catalyst is able to be reemployed up to five times. Statistical analysis has been performed using a Central Composite Design to evaluate the contribution and performance of the parameters on biodiesel purity
    corecore