10 research outputs found
Machine learning prediction of the unconfined compressive strength of controlled low strength material using fly ash and pond ash
No full textAbstract The sustainable use of industrial byproducts in civil engineering is a global priority, especially in reducing the environmental impact of waste materials. Among these, coal ash from thermal power plants poses a significant challenge due to its high production volume and potential for environmental pollution. This study explores the use of controlled low-strength material (CLSM), a flowable fill made from coal ash, cement, aggregates, water, and admixtures, as a solution for large-scale coal ash utilization. CLSM is suitable for both structural and geotechnical applications, balancing waste management with resource conservation. This research focuses on two key CLSM properties: flowability and unconfined compressive strength (UCS) at 28 days. Traditional testing methods are resource-intensive, and empirical models often fail to accurately predict UCS due to complex nonlinear relationships among variables. To address these limitations, four machine learning models—minimax probability machine regression (MPMR), multivariate adaptive regression splines (MARS), the group method of data handling (GMDH), and functional networks (FN) were employed to predict UCS. The MARS model performed best, achieving R2 values of 0.9642 in training and 0.9439 in testing, with the lowest comprehensive measure (COM) value of 1.296. Sensitivity analysis revealed that cement content was the most significant factor with obtaining R = 0.88, followed by water (R = 0.82), flowability (R = 0.79), pond ash (R = 0.78), curing period (R = 0.73), and fine content (R = 0.68), with fly ash (R = 0.55) having the least impact. These machine learning models provide superior accuracy compared to traditional methods, particularly in handling complex interactions between mix components. The proposed models offer a practical approach for predicting CLSM performance, supporting sustainable construction practices and the efficient use of industrial byproducts. The novelty of this study lies in the development of precise design equations for evaluating UCS, promoting both practical applicability and environmental sustainability
Predicting the UCS of Industrial Byproduct-Based CLSM Using Machine Learning and Experiments
No full textThis study investigated the development of sustainable Controlled Low Strength Material (CLSM) using industrial by-products pond ash, fly ash, and red mud as alternatives to conventional concrete constituents. This research employs a dual methodology: comprehensive experimental testing aligned with ASTM standards and the implementation of advanced machine learning (ML) techniques to predict the unconfined compressive strength (UCS) of CLSM mixes. Experimental datasets, generated through the variation of key material and mix design parameters, were utilized to train ensemble-based supervised ML models, including ADAboost, XGBoost, gradient boosting machine (GBM), and random forest (RF). A comparative performance evaluation was conducted, and the XGBoost model emerged as the most accurate predictor, achieving R² values of 0.969 for training and 0.933 for testing, surpassing GBM, ADAboost, and RF across multiple performance indicators. The optimal model was subsequently embedded into a graphical user interface (GUI) for UCS prediction. A sensitivity analysis based on the XGBoost model revealed that cement, water, and curing age were the most influential parameters affecting UCS, with cement exhibiting the highest impact value of 0.86 and a relative contribution of 19%. These findings emphasize the significance of these variables in strength development and mix optimization. The integration of experimental validation with predictive modeling not only advances the understanding of CLSM behavior but also underscores the utility of ML in the formulation of sustainable construction materials. This research supports the beneficial reuse of industrial waste, aligns with environmental sustainability goals, and provides an efficient and reliable tool for CLSM mix design
Architecture and permeability structure of the Sibillini Mts. Thrust and influence upon recent, extension-related seismicity in the central Apennines (Italy) through fault-valve behavior
No full textThe central Apennines are a fold-thrust belt currently affected by post-orogenic ex-tensional seismicity. To constrain the influ-ence that the inherited thrust-related struc-tures exert on the present seismic behavior of the belt, we provide the high-resolution structural and hydraulic characterization of one of the most external exposed thrust fault systems of the central Apennines, the Sibil-lini Mts. Thrust Front (STF). We integrate structural mapping, multiscale structural analysis, and in situ air permeability on the brittle structural facies of the thrust zone. We also performed K-Ar dating of selected fault rocks to better constrain structural in-heritance. The STF is defined by a complex, similar to 300-m-thick deformation zone involving Meso-Cenozoic marl and limestone that re-sults from the accommodation of both seis-mic and aseismic slip during shortening. Permeability measurements indicate that the low permeability (10-2 divided by 10-3 D) of the marly rich host rock diminishes within the thrust zone, where the principal slip surfaces and associated S-C structures represent efficient hydraulic barriers (permeability down to similar to 3 x 10-10 D) to sub-vertical fluid flow. Field data and K-Ar dating indicate that the STF began its evolution ca. 7 Ma (early Messin-ian). We suggest that the studied thrust zone may represent a barrier for the upward migration of deep fluids at the hypocentral depth of present-day extensional earth-quakes. We also speculate on the influence that similar deformation zones may have at depth on the overall regional seismotectonic pattern by causing transient fluid overpres-sures and, possibly, triggering cyclic exten-sional earthquakes on normal faults prone to slip while crosscutting the earlier thrust zones (as per a classic fault valve behavior). This mechanism may have controlled the ori-gin of the 2016-2017 central Apennines dev-astating earthquakes
Association Between PMTCT Services Utilization Among HIV Positive Mothers and HIV Status of their HIV-Exposed Children in Mtwara District, Tanzania
No full textAlthough without any intervention in PMTCT up to 80% of HIV exposed children could not be infected with HIV, PMTCT interventions provide a critical opportunity to prevent vertical transmission of HIV from mother to child during pregnancy, labour and delivery and/or during breastfeeding. The objective of the study therefore was to determine the association between utilization of PMTCT services among HIV positive mothers with children aged 6 to 24 months and HIV status of their exposed children attending post-natal clinics in Mtwara Rural District. The study was carried out between July and August 2012. Analytical cross sectional study using structured questionnaire among 130 HIV positive mothers who had children aged between 6 to 24 months was employed. Random sampling of Health Facilities were done followed by conveniently sampling to select participants, where all HIV positive mothers (who fulfilled the inclusion criteria) who attended the clinic during the time of data collection were consecutively included in the study till the sample size reached. About 10% of children born by mothers who knew their HIV positive status before pregnancy and they were on ARV treatment were infected with HIV compared to 50% of children born by mothers who were not on ART treatment before pregnancy (χ2=4.3, p = 0.038). Transmission rate of HIV from mother to child among mothers whoreceived ARV‘s for PMTCT during pregnancy was 15.5% compared to 58.8% of mothers who do not received ARV‘s for PMTCT during pregnancy. Regardless of intervention, the prevalence of HIV among exposed children who had mixed feeding was 36.1% while for those who were exclusively breastfed/formula fed was 13.8% (χ2= 8.077, p = 0.004). Reduction of MTCT of HIV is possible with effective PMTCT interventions, including access to ARV‘s for PMTCT by mothers during pregnancy, labour, and during lactation period and also for exposed children from birth till when they stopped breastfed or proven to be HIV infected. Appropriate infant feeding practices is also crucial in reduction of MTCT. Strategies to address programmatic challenges of lower ANC attendance, low facility delivery and low post-natal care attendance in rural Tanzania which contribute to low uptake of ARV prophylaxis for PMTCT during pregnancy, labour and after delivery observed in this study are essential
The PRISM4 (mid-Piacenzian) palaeoenvironmental reconstruction
No full textThe mid-Piacenzian is known as a period of relative warmth when compared to the present day. A comprehensive understanding of conditions during the Piacenzian serves as both a conceptual model and a source for boundary conditions and means of verification of global climate model experiments. In this paper we present the PRISM4 reconstruction, a palaeoenvironmental reconstruction of the mid-Piacenzian (~ 3 Ma) containing data for palaeogeography, land and sea-ice, sea-surface temperature, vegetation, soils and lakes. Our retrodicted palaeogeography takes into account glacial isostatic adjustments and changes in dynamic topography. Soils and lakes, both significant as land surface features, are introduced to the PRISM reconstruction for the first time. Sea-surface temperature and vegetation reconstructions are unchanged but now have confidence assessments. The PRISM4 reconstruction is being used as boundary condition data for the Pliocene Model Intercomparison Project, Phase 2 (PlioMIP2) experiments
Advances in plant gene-targeted and functional markers: a review
No full textPublic genomic databases have provided new directions for molecular marker development and initiated a shift in
the types of PCR-based techniques commonly used in plant science. Alongside commonly used arbitrarily amplified
DNA markers, other methods have been developed. Targeted fingerprinting marker techniques are based on the
well-established practices of arbitrarily amplified DNA methods, but employ novel methodological innovations such
as the incorporation of gene or promoter elements in the primers. These markers provide good reproducibility and
increased resolution by the concurrent incidence of dominant and co-dominant bands. Despite their promising
features, these semi-random markers suffer from possible problems of collision and non-homology analogous to
those found with randomly generated fingerprints. Transposable elements, present in abundance in plant genomes,
may also be used to generate fingerprints. These markers provide increased genomic coverage by utilizing specific
targeted sites and produce bands that mostly seem to be homologous. The biggest drawback with most of these
techniques is that prior genomic information about retrotransposons is needed for primer design, prohibiting
universal applications. Another class of recently developed methods exploits length polymorphism present in arrays
of multi-copy gene families such as cytochrome P450 and β-tubulin genes to provide cross-species amplification
and transferability. A specific class of marker makes use of common features of plant resistance genes to generate
bands linked to a given phenotype, or to reveal genetic diversity. Conserved DNA-based strategies have limited
genome coverage and may fail to reveal genetic diversity, while resistance genes may be under specific
evolutionary selection. Markers may also be generated from functional and/or transcribed regions of the genome
using different gene-targeting approaches coupled with the use of RNA information. Such techniques have the
potential to generate phenotypically linked functional markers, especially when fingerprints are generated from the
transcribed or expressed region of the genome. It is to be expected that these recently developed techniques will
generate larger datasets, but their shortcomings should also be acknowledged and carefully investigated
The Ncm-1 gene for resistance to Cucumber mosaic virus in yellow lupin (Lupinus luteus): molecular studies and marker development
No full textCucumber mosaic virus (CMV) is an important virus pathogen of lupins in Australia which causes serious yield losses of up to 60% in epidemic years. In commercially grown lupin (Lupinus angustifolius and L. luteus) crops CMV is spread non-persistently by aphid vectors, but it can also be seed borne and this extends virus infection into successive generations. Resistance to CMV has been identified in L. luteus cv. Wodjil and is the conferred by the Ncm-1 gene. The aims of this research were to study the Ncm-1 gene in order to gain a better understanding of resistance in yellow lupin, and to develop a molecular marker linked to Ncm-1 for use in marker assisted selection.
Previously published data by Jones et al (1996) identified Ncm-1 as being a single dominant resistance gene, however, phenotypic analysis of CMV infection in a segregating L. luteus mapping population in this thesis was consistent with the Ncm-1 gene being a dominant gene modified by at least one other minor gene. The polygenic nature of CMV resistance in this genetic background was further supported by AFLP analysis which identified one major and one minor QTL associated with resistance.
A PCR based approach, using degenerate primers designed on conserved disease resistance protein motifs, was used to identify resistance gene analogues (RGA) in L. luteus. Comparative analysis revealed that RGAs isolated from L. luteus were members of the TIR-NBS-LRR class of R proteins and were similar to the TMV resistance gene N identified in tobacco and the RT4-4 CMV resistance gene from pepper. Extensive comparative analysis using the genomes of model species (including Medicago truncatula, Glycine max, Arabidopsis thaliana and Lotus japonicus) was explored and validated the assignment from L. luteus RGAs to the category of candidate gene for CMV resistance. The RGAs identified in L. luteus were found to be highly conserved in both the CMV resistant and susceptible varieties tested. SNPs which resulted in non-synonymous mutations were identified using cDNA based 5’ RACE and used to develop a single nucleotide primer extension (SNuPE) assays for MALDI-ToF mass spectrophotometric analysis. As SNuPE is based on the allele specific extension of a single nucleotide, genotyping is highly accurate and provides co-dominant information. Two SNuPE assays were developed based on the RGAs isolated and validated on bulked samples from two L.luteus populations segregating for CMV resistance. One assay, SNuPE A267→C was found to associate with CMV resistance. This co-dominant assay is the first of its kind reported for yellow lupin
Bio-control of root rot disease in vanilla
No full textA thesis submitted in partial fulfilment of the
requirements of the University of Wolverhampton
for the degree of Doctor of PhilosophyFusarium oxysporum Schl. var. vanillae (Tucker) Gondon is known to cause root rot in Vanilla planifolia Andrews in most regions where it is grown, including the major plantations in Xishuangbanna, Yunnan Province of China. This is of serious economic concern to the Province since the vanilla flavouring extractable from the beans of the plant is a valuable food product and an important export commodity. There are no fungicides registered for the control of Fusarium root rot and the only available chemical control methods are ineffective and cause serious contamination of the soil. Breeding for resistance is difficult when no dominant gene is known or where little information is available on fungal pathogenicity. Biocontrol is the main alternative for disease control in this crop, an attractive approach because of increasing concerns for environmental protection. The investigation considers two biocontrol strategies: first the introduction of virulent, antagonistic, non-pathogenic strains, closely-related to the pathogen, to overcome pathogenic populations in infected soils; second the use of essential oils with antimicrobial properties when applied to infected soils. Pathogenicity tests have been done on 81 out of 87 F. oxysporum isolates collected in Yunnan Province. Among these, 32 isolates were non-pathogenic and 49 were pathogenic. The pathogenicity results showed the complexity of F. oxysporum in Yunnan. Seventeen isolates were recovered from the Daluo plantation, of which 14 were pathogenic isolates and 3 non-pathogenic isolates; 26 from the Menglun plantation, in which 12 were pathogenic and 14 were non-pathogenic; 18 isolates from the Manjingdai plantation, in which 12 isolates were pathogenic, whilst the other 6 were non-pathogenic and 20 were obtained from the plantation in Hekou i County, of which 11 were pathogenic isolates and 9 were non-pathogenic. Genetic diversity within this population of F. oxysporum has been investigated with respect to vegetative compatibility and to determine the relationship between VCGs and virulence. The VCG results showed that the 87 strains of Fusarium oxysporum f.sp vanillae isolated from Yunnan Province were complex. They could be distributed into 12 different VCGs and that a direct relationship between VCGs group and virulence could not be drawn. Two non-pathogenic strains, ML-5-2 and HK-5b-4-1, have been screened from 87 strains as candidate biocontrol agents by pathogenicity and VCG, which are self-incompatible and closely related to the pathogens. These two strains were effective in vanilla root rot control in controlled environments, but their effects in field experiments were less conclusive. Seven essential oils, which have long been regarded as having inhibitory effects on pathogens in nature, have also been investigated as biocontrol agents. Three oils, cinnamon oil, thyme oil and clove oil, were effective in inhibiting the growth of pathogen in vitro. These oils may develop into useful components of different management strategies with non-pathogenic strains. For the future, consideration will need to be given to the mechanism(s) of the interaction of the antagonistic components with the soil microbe population and host plant and also to appropriate formulation, to take account of soil type, crop status, cultural practices, environmental and economic factors. Biocontrol methods have considerable potential but must be acceptable to farmers as part of an overall crop management programme
Development of a functional prototype of an eye-tracking spelling system as an alternative for the communication of ALS patients
No full textLa Esclerosis Lateral Amiotrófica (ELA), es una enfermedad neurodegenerativa que afecta principalmente a las células motoras del cerebro y la médula espinal, causando una pérdida progresiva de los músculos voluntarios del cuerpo y limitando la capacidad de movimiento y comunicación de quienes la padecen. A lo largo de la enfermedad, la habilidad para hablar y expresarse de manera convencional puede disminuir, lo que impulsa la búsqueda de alternativas tecnológicas para una comunicación efectiva y no invasiva. Por tanto, el objetivo de nuestro trabajo de grado es mejorar la calidad de vida de las personas con ELA mediante el desarrollo de un prototipo funcional de un sistema de deletreo de bajo costo, utilizando la tecnología de seguimiento ocular.
La metodología se dividió en cuatro etapas, acordes a los objetivos específicos propuestos: diseño, desarrollo, implementación y evaluación. En la etapa de diseño se realizó el levantamiento de información sobre softwares, librerías, cámaras y sistemas de iluminación para crear la interfaz hombre-máquina y el menú de inicio. En la etapa de desarrollo, se creó el algoritmo fundamental del proyecto para detectar con precisión la posición del ojo y los movimientos oculares en tiempo real. En la etapa de implementación se integraron, la interfaz diseñada y el algoritmo desarrollado y así preparar el sistema para el envío del mensaje generado a un dispositivo móvil.
Finalmente, en la etapa de evaluación, se probó el sistema con 8 sujetos sanos quienes realizaron una serie de tareas con el objetivo de evaluar su rendimiento y garantizar la fiabilidad y la precisión del sistema mediante dos métodos de control de cursor. El primer método consiste en la captación de los movimientos oculares tomando como referencia el aprendizaje realizado durante la etapa de calibración. El segundo método, basado en la interpolación lineal consiste en la extracción de información de los movimientos oculares a partir del cálculo de las coordenadas de la posición de la letra/número/botón hacia donde el sujeto estaba observando. Este segundo método demostró ser el más robusto por lograr una precisión superior al 96% destacando la eficiencia y éxito del sistema en términos de usabilidad y rendimiento, proporcionando así una alternativa viable para mejorar la comunicación y la independencia de las personas con ELA.BioingenieroPregradoAmyotrophic Lateral Sclerosis (ALS) is a neurodegenerative disease that primarily affects the motor cells of the brain and spinal cord, causing a progressive loss of the body's voluntary muscles and limiting the ability of sufferers to move and communicate. Throughout the course of the disease, the ability to speak and express oneself in a conventional manner may diminish, prompting the search for technological alternatives for effective and non-invasive communication. Therefore, the objective of our degree work is to improve the quality of life of people with ALS by developing a functional prototype of a low-cost spelling system using eye-tracking technology.
The methodology was divided into four stages, according to the specific objectives proposed: design, development, implementation and evaluation. In the design stage, information on software, libraries, cameras and lighting systems was gathered to create the human-machine interface and the start menu. In the development stage, the fundamental algorithm of the project was created to accurately detect eye position and eye movements in real time. In the implementation stage, the designed interface and the developed algorithm were integrated to prepare the system for sending the generated message to a mobile device.
Finally, in the evaluation stage, the system was tested with 8 healthy subjects who performed a series of tasks in order to evaluate its performance and ensure the reliability and accuracy of the system using two cursor control methods. The first method consists of capturing eye movements based on the learning performed during the calibration stage. The second method, based on linear interpolation, consists of extracting information from the eye movements by calculating the coordinates of the position of the letter/number/button to which the subject was looking.
This second method proved to be the most robust by achieving an accuracy of over 96% highlighting the efficiency and success of the system in terms of usability and performance, thus providing a viable alternative to improve communication and independence of people with ALS
