Search results for: non-destructive testing (NDT)

Authors: Lina T. Codilla

Abstract:

This study primarily designed a laboratory activity in ecology to demonstrate the allelopathic property of the Philippine Chromolaena odorata L. (hagonoy) leaf extracts to Lycopersicum esculentum (M), commonly known as tomatoes. Ethanol extracts of C. odorata leaves were tested on seed germination and seedling growth of L. esculentum in 7-day and 14-day observation periods. Analysis of variance and Tukey’s HSD post hoc test was utilized to determine differences among treatments while Pre–test – Post–test experimental design was utilized in the determination of the effectiveness of the designed laboratory activity. Results showed that the 0.5% concentration level of ethanol leaf extracts significantly inhibited germination and seedling growth of L. esculentum in both observation periods. These results were used as the basis in the development of instructional material in ecology. The laboratory activity underwent face validation by five (5) experts in various fields of specialization, namely, Biological Sciences, Chemistry and Science Education. The readability of the designed laboratory activity was determined using a Cloze Test. Pilot testing was conducted and showed that the laboratory activity developed is found to be a very effective tool in supplementing learning about allelopathy in ecology class. Thus, it is recommended for use among ecology classes but modification will be made in a small – scale basis to minimize time consumption.

Keywords: allelopathy, chromolaena odorata l. (hagonoy), designed-laboratory activity, organic herbicide students’ performance

Procedia PDF Downloads 294

Authors: Siti Ayu Ningsih

Abstract:

This study aims to find the differences outcomes in learning reading comprehension with text and film as media on Indonesian Language for foreign speaker (BIPA) learning at intermediate level. By using quantitative and qualitative research methods, the respondent of this study is a single respondent from D'Royal Morocco Integrative Islamic School in grade nine from secondary level. Quantitative method used to calculate the learning outcomes that have been given the appropriate action cycle, whereas qualitative method used to translate the findings derived from quantitative methods to be described. The technique used in this study is the observation techniques and testing work. Based on the research, it is known that the use of the text media is more effective than the film for intermediate level of Indonesian Language for foreign speaker learner. This is because, when using film the learner does not have enough time to take note the difficult vocabulary and don't have enough time to look for the meaning of the vocabulary from the dictionary. While the use of media texts shows the better effectiveness because it does not require additional time to take note the difficult words. For the words that are difficult or strange, the learner can immediately find its meaning from the dictionary. The presence of the text is also very helpful for Indonesian Language for foreign speaker learner to find the answers according to the questions more easily. By matching the vocabulary of the question into the text references.

Keywords: Indonesian language for foreign speaker, learning outcome, media, reading comprehension

Procedia PDF Downloads 197

Authors: Behnaz Moradijamei, Michael Higgins

Abstract:

Identifying community structure is a critical task in analyzing social media data sets often modeled by networks. Statistical models such as the stochastic block model have proven to explain the structure of communities in real-world network data. In this work, we develop a goodness-of-fit test to examine community structure's existence by using a distinguishing property in networks: cyclic structures are more prevalent within communities than across them. To better understand how communities are shaped by the cyclic structure of the network rather than just the number of edges, we introduce a novel method for deciding on the existence of communities. We utilize these structures by using renewal non-backtracking random walk (RNBRW) to the existing goodness-of-fit test. RNBRW is an important variant of random walk in which the walk is prohibited from returning back to a node in exactly two steps and terminates and restarts once it completes a cycle. We investigate the use of RNBRW to improve the performance of existing goodness-of-fit tests for community detection algorithms based on the spectral properties of the adjacency matrix. Our proposed test on community structure is based on the probability distribution of eigenvalues of the normalized retracing probability matrix derived by RNBRW. We attempt to make the best use of asymptotic results on such a distribution when there is no community structure, i.e., asymptotic distribution under the null hypothesis. Moreover, we provide a theoretical foundation for our statistic by obtaining the true mean and a tight lower bound for RNBRW edge weights variance.

Keywords: hypothesis testing, RNBRW, network inference, community structure

Procedia PDF Downloads 150

Authors: Bernhard Widhalm, Cornelia Rieder-Gradinger, Ewald Srebotnik

Abstract:

Pine wood (Pinus sylvestris L.) is the basic raw material for the production of Oriented Strand Boards (OSB) and the major source of volatile organic compounds, especially terpenes (like α- and β-pinene). To lower the total emission level of OSB, terpene metabolising microorganisms were therefore applied onto pine wood strands for the production of emission-reduced boards. Suitable microorganisms were identified during preliminary tests under laboratory conditions. At first, their terpene degrading potential was investigated in liquid culture, followed by laboratory tests using unsterile pine wood particles and strands. The main focus was laid on an adoptable terpene reduction in a short incubation time. An optimised bacterial mixture of Pseudomonas putida and Pseudomonas fluorescens showed the best results and was therefore used for further experiments on a larger scale. In an industry-compatible testing procedure, pine wood strands were incubated with the bacterial mixture for a period of 2 to 4 days. Incubation time was stopped by drying the strands. OSB were then manufactured from the pre-treated strands and emissions were measured by means of SPME/GC-MS analysis. Bacterial pre-treatment of strands resulted in a reduction of α-pinene- and β-pinene-emissions from OSB by 40% and 70%, respectively, even after only 2 days of incubation. The results of the investigation provide a basis for the application of microbial treatment within the industrial OSB production line, where shortest possible incubation times are required. For this purpose, the performance of the bacterial mixture will have to be further optimised.

Keywords: GC-MS, OSB, Pseudomonas sp., terpene degradation

Procedia PDF Downloads 268

Authors: W. Sornlar, S. Supothina, A. Wannagon

Abstract:

Lightweight geopolymer can be prepared by using some foaming agents, such as metal powders or hydrogen peroxide; however, it is difficult to control the generated cell size due to the high reactivity of the system. This study aims to investigate the influence of Sodium Lauryl Ether Sulfate (SLES) foam addition and curing temperature on the physical, mechanical, thermal, and microstructure behaviors of the lightweight kaolinite-based geopolymer. To provide porous structure, the geopolymer paste was mixed with 0-15 wt% of SLES foam before casting into the mold. Testing and characterizations were carried out after 28 days. The results showed that SLES foam generated the regular and spherical macropores, which were well distributed in the geopolymer samples. The total porosity increased as SLES foam increased, similarly as the apparent porosity and water absorption. On the other hand, the bulk density and mechanical strength decreased as SLES foam increased. Curing temperature was studied simultaneously due to it strongly affects the mechanical strength of geopolymer. In this study, rising of curing temperature from 27 to 50°C (at 75% relative humidity) improved the compressive strength of samples but deteriorated after curing at 60°C. Among them, the composition of 15 wt% SLES foam (NF15) presented the highest porosity (70.51-72.89%), the lowest density (0.68-0.73 g/cm³), and very low thermal conductivity (0.172-0.197 W/mK). It had the proper compressive strength of 4.21-4.74 MPa that can be applied for the thermal insulation.

Keywords: lightweight, kaolinite-based geopolymer, curing temperature, foaming agent, thermal conductivity

Procedia PDF Downloads 181

Authors: Dragana Gnjatovic

Abstract:

Assessment is a burning topic in education policy and practice due to measurement-driven neoliberal agendas of quality and standardisation of assessment practice through high stakes standardised testing systems that are now influencing early childhood education. This paper presents a collaborative, arts-informed action research project which places children at the centre of their learning, with assessment as an integral part of play-based learning processes. It aims to challenge traditional approaches to assessment that are often teacher-led and decontextualised from the processes of learning through exploring approaches where children's voices are central, and their creative arts expressions are used to assess learning and development. The theoretical framework draws on Vygotsky's sociocultural theory and Freire's critical pedagogy, which indicate the importance of socially constructed reality where knowledge is the result of collaboration between children and adults. This reality perceives children as competent agents of their own learning processes. An interpretive-constructivist and critical-transformative paradigm underpin collaborative action research in a three to five-year-old setting, where creative methods like storytelling, play, drama, drawing are used to assess children's learning. As data collection and analysis are still in process, this paper will present the methodology and some data vignettes, with the aim of stimulating discussion about innovation in assessment and contribution of the collaborative enquiry in the field of Early Childhood Education and Care.

Keywords: assessment for learning, creative methodologies, collaborative action research, early childhood education and care

Procedia PDF Downloads 135

Authors: Subir Gupta, Subhas Ganguly

Abstract:

In this paper, we demonstrate the new area of application of image processing in metallurgical images to develop the more opportunity for structure-property correlation based approaches of alloy design. The present exercise focuses on the development of image processing tools suitable for phrase segmentation, grain boundary detection and recognition of micro-constituents in SEM micrographs of ferrite and pearlite steels. A comprehensive data of micrographs have been experimentally developed encompassing the variation of ferrite and pearlite volume fractions and taking images at different magnification (500X, 1000X, 15000X, 2000X, 3000X and 5000X) under scanning electron microscope. The variation in the volume fraction has been achieved using four different plain carbon steel containing 0.1, 0.22, 0.35 and 0.48 wt% C heat treated under annealing and normalizing treatments. The obtained data pool of micrographs arbitrarily divided into two parts to developing training and testing sets of micrographs. The statistical recognition features for ferrite and pearlite constituents have been developed by learning from training set of micrographs. The obtained features for microstructure pattern recognition are applied to test set of micrographs. The analysis of the result shows that the developed strategy can successfully detect the micro constitutes across the wide range of magnification and variation of volume fractions of the constituents in the structure with an accuracy of about +/- 5%.

Keywords: SEM micrograph, metallurgical image processing, ferrite pearlite steel, microstructure

Procedia PDF Downloads 199

Authors: Naohiro Nakamura

Abstract:

Analysis methods to accurately estimate the behavior of buildings when earthquakes occur is very important for improving the seismic safety of such buildings. Recently, the use of damping devices has increased significantly and there is a particular need to appropriately evaluate the behavior of buildings with such devices during earthquakes in the design stage. At present, however, the accuracy of the analysis evaluations is not sufficient. One reason is that the accuracy of current analysis methods has not been appropriately verified because there is very limited data on the behavior of actual buildings during earthquakes. Many types of shaking table test of large structures are performed at the '3-Dimensional Full-Scale Earthquake Testing Facility' (nicknamed 'E-Defense') operated by the National Research Institute of Earth Science and Disaster Prevention (NIED). In this study, simulations using 3- dimensional analysis models were conducted on shaking table test of a 5-story steel-frame structure with dampers. The results of the analysis correspond favorably to the test results announced afterward by the committee. However, the suitability of the parameters and models used in the analysis and the influence they had on the responses remain unclear. Hence, we conducted additional analysis and studies on these models and parameters. In this paper, outlines of the test are shown and the utilized analysis model is explained. Next, the analysis results are compared with the test results. Then, the additional analyses, concerning with the hysteresis curve of the dampers and the beam-end stiffness of the frame, are investigated.

Keywords: three-dimensional analysis, E-defense, full-scale experimen, vibration control damper

Procedia PDF Downloads 190

Authors: Zerrin Orbak, Busra Demir

Abstract:

Osteopetrosis is a rare genetic disease characterized by impaired bone resorption and increased bone sclerosis. Clinical presentation is very different in osteopetrosis. It can be asymptomatic or can be seen with typical symptoms. Here, a case of osteopetrosis was presented when evaluated for nystagmus. She was 10 months old. Parents were second-degree relatives. On physical examination, pigeon chest deformity and horizontal nystagmus were observed. There was a failure of thrive but no fracture. The cardiovascular examination was normal. Cranial, vertebral and long bone roentgenograms revealed characteristic deformities of osteopetrosis and diffuse sclerosis. The diagnosis was confirmed by genetic testing. A Homozygous mutation was detected in the TNFRSF11A gene (c.508A>G p.(Arg170Gly)). RANKL is encoded by the tumor necrosis factor ligand superfamily member 11 (TNFSF11) gene, and the binding to its receptor RANK, encoded by the TNFRSF11A gene, determines the activation of the downstream pathway that drives osteoclast differentiation and activation (51). The complete absence of osteoclasts is the key feature of the osteoclast-poor form of osteopetrosis (46). Patients are characterized by the absence of TRAP-positive osteoclasts in bone biopsies. The osteoclast-poor subtype of osteopetrosis caused by mutations in TNFSF11 gene is ultra-rare in humans. Clinical presentation is usually severe, with onset in early infancy or in fetal life. But here, a case was presented with horizontal nystagmus. A case presented with horizontal nystagmus, which was evaluated by neurology and diagnosed incidentally, was shared.

Keywords: osteopetrosis, nystagmus, bone, osteoclast-poor

Procedia PDF Downloads 87

Authors: Lia Gventsadze, Elguja Kutelia, David Gventsadze

Abstract:

The purpose of the article is to show the possibility for the development of a new generation, eco-friendly (asbestos free) nano-porous friction materials on the basis of Georgian raw materials, along with the determination of technological parameters for their production, as well as the optimization of tribological properties and the investigation of structural aspects of wear peculiarities of elaborated materials using the scanning electron microscopy (SEM) and Auger electron spectroscopy (AES) methods. The study investigated the tribological properties of the polymer friction materials on the basis of the phenol-formaldehyde resin using the porous diatomite filler modified by silane with the aim to improve the thermal stability, while the composition was modified by iron phosphate, technical carbon and basalt fibre. As a result of testing the stable values of friction factor (0.3-0,45) were reached, both in dry and wet friction conditions, the friction working parameters (friction factor and wear stability) remained stable up to 500 OC temperatures, the wear stability of gray cast-iron disk increased 3-4 times, the soundless operation of materials without squeaking were achieved. Herewith it was proved that small amount of ingredients (5-6) are enough to compose the nano-porous friction materials. The study explains the mechanism of the action of nano-porous composition base brake lining materials and its tribological efficiency on the basis of the triple phase model of the tribo-pair.

Keywords: brake lining, friction coefficient, wear, nanoporous composite, phenolic resin

Procedia PDF Downloads 393

Authors: Anthony Ayodeji Adegoke, Olayinka Ayobami Aiyegoro, Thor Axel Stenstrom

Abstract:

A study to investigate the species diversities, antibiogram and antibiotic resistance genes in Staphylococcus species from raw meat and dairy products collected from an abattoir and a farm shop of a research institute in Irene, South Africa over a six-month period was conducted. Polymerase Chain Reaction was used to speciate the bacteria and to detect the presence and otherwise of resistance genes. Antibiotic susceptibility testing was performed by disk diffusion method on Mueller-Hinton agar according to the Clinical Laboratory Standards Institute standards. A total of twenty-six (26) antibiotics were used to determine the antibiotic susceptibility. S. xylosus was the predominant isolate with 30% total occurrence, followed by S. epidermis, S. aureus, S. saprophyticus and S. haemolyticus with 25%, 15%, 15%, and 10% abundance respectively. The isolates were resistant to ceftezidime, gentamycin, nalidixic acid, nortrafuration, ampicillin, penicillin, oxytetracycline, tetracycline, doxycycline, clindamycin and lincomycin. mecA genes was detected among the methicillin resistant Staphylococcus species (MRSS) but no vancomycin resistance genes (van A and van B) were detected in these isolates. The presence of MRSS and multidrug resistant Staphylococcus species in meat affirms the need to avoid consumption of partially cooked meat currently rampant in South Africa, to avoid the spread of difficult to control pathogens in epidemiological proportion.

Keywords: Staphylococcus species, antibiotics, antibiotic resistance genes, food products, methicillin resistance, mecA gene

Procedia PDF Downloads 299

Authors: A. Khodabakhshi, A. Mortazavi

Abstract:

Accurate determination of rock mass deformation modulus, as an important design parameter, is one of the most controversial issues in most engineering projects. A 3D numerical model of standard plate load test (PLT) using the FLAC3D code was carried to investigate the mechanism governing the test process. Five objectives were the focus of this study. The first goal was to employ 3D modeling in the interpretation of PLT conducted at the Bazoft dam site, Iran. The second objective was to investigate the effect of displacements measuring depth from the loading plates on the calculated moduli. The magnitude of rock mass deformation modulus calculated from PLT depends on anchor depth, and in practice, this may be a cause of error in the selection of realistic deformation modulus for the rock mass. The third goal of the study was to investigate the effect of testing plate diameter on the calculated modulus. Moreover, a comparison of the calculated modulus from ISRM formula, numerical modeling and calculated modulus from the actual PLT carried out at right abutment of the Bazoft dam site was another objective of the study. Finally, the effect of plastic strains on the calculated moduli in each of the loading-unloading cycles for three loading plates was investigated. The geometry, material properties, and boundary conditions on the constructed 3D model were selected based on the in-situ conditions of PLT at Bazoft dam site. A good agreement was achieved between numerical model results and the field tests results.

Keywords: deformation modulus, numerical model, plate loading test, rock mass

Procedia PDF Downloads 170

Authors: Naduni Ranasinghe

Abstract:

E-learning environments are getting more popular than any other due to the impact of COVID19. Even though e-learning is one of the best solutions for the teaching-learning process in the academic process, it’s not without major challenges. Nowadays, machine learning approaches are utilized in the analysis of how behavioral factors lead to better adoption and how they related to better performance of the students in eLearning environments. During the pandemic, we realized the academic process in the eLearning approach had a major issue, especially for the performance of the students. Therefore, an approach that investigates student behaviors in eLearning environments using a data-intensive machine learning approach is appreciated. A hybrid approach was used to understand how each previously told variables are related to the other. A more quantitative approach was used referred to literature to understand the weights of each factor for adoption and in terms of performance. The data set was collected from previously done research to help the training and testing process in ML. Special attention was made to incorporating different dimensionality of the data to understand the dependency levels of each. Five independent variables out of twelve variables were chosen based on their impact on the dependent variable, and by considering the descriptive statistics, out of three models developed (Random Forest classifier, SVM, and Decision tree classifier), random forest Classifier (Accuracy – 0.8542) gave the highest value for accuracy. Overall, this work met its goals of improving student performance by identifying students who are at-risk and dropout, emphasizing the necessity of using both static and dynamic data.

Keywords: academic performance prediction, e learning, learning analytics, machine learning, predictive model

Procedia PDF Downloads 157

Authors: Abdul Manan

Abstract:

The necessity for efficient and cost-effective energy storage devices to intelligently store the inconsistent energy output from modern renewable energy sources is peaked today. The scientific community is struggling to identify the appropriate material system for energy storage applications. Countless contributions by researchers worldwide have now helped us identify the possible snags and limitations associated with each material/method. Energy storage has attracted great attention for its use in portable electronic devices military field. Different devices, such as dielectric capacitors, supercapacitors, and batteries, are used for energy storage. Of these, dielectric capacitors have high energy output, a long life cycle, fast charging and discharging capabilities, work at high temperatures, and excellent fatigue resistance. The energy storage characteristics have been studied to be highly affected by various factors, such as grain size, optimized compositions, grain orientation, energy band gap, processing techniques, defect engineering, core-shell formation, interface engineering, electronegativity difference, the addition of additives, density, secondary phases, the difference of Pmax-Pr, sample thickness, area of the electrode, testing frequency, and AC/DC conditions. The data regarding these parameters/factors are scattered in the literature, and the aim of this study is to gather the data into a single paper that will be beneficial for new researchers in the field of interest. Furthermore, control over and optimizing these parameters will lead to enhancing the energy storage properties.

Keywords: strategies, ceramics, energy storage, capacitors

Procedia PDF Downloads 77

Authors: Marcus Klein, Martina GrießBach, Richard Kupke

Abstract:

The current advances in the research and manufacturing of large area graphene layers are promising towards the introduction of this exciting material in the display industry and other applications that benefit from excellent electrical and optical characteristics. New production technologies in the fabrication of flexible displays, touch screens or printed electronics apply graphene layers on non-metal substrates and bring new challenges to the required metrology. Traditional measurement concepts of layer thickness, sheet resistance, and layer uniformity, are difficult to apply to graphene production processes and are often harmful to the product layer. New non-contact sensor concepts are required to adapt to the challenges and even the foreseeable inline production of large area graphene. Dedicated non-contact measurement sensors are a pioneering method to leverage these issues in a large variety of applications, while significantly lowering the costs of development and process setup. Transferred and printed graphene layers can be characterized with high accuracy in a huge measurement range using a very high resolution. Large area graphene mappings are applied for process optimization and for efficient quality control for transfer, doping, annealing and stacking processes. Examples of doped, defected and excellent Graphene are presented as quality images and implications for manufacturers are explained.

Keywords: graphene, doping and defect testing, non-contact sheet resistance measurement, inline metrology

Procedia PDF Downloads 307

Authors: Kristian Bautista, Ruben A. Idoy

Abstract:

A bio-inspired metaheuristic algorithm inspired by the theory of collective animal behavior (CAB) was integrated to density-based clustering modeled as multimodal optimization problem. The algorithm was tested on synthetic, Iris, Glass, Pima and Thyroid data sets in order to measure its effectiveness relative to CDE-based Clustering algorithm. Upon preliminary testing, it was found out that one of the parameter settings used was ineffective in performing clustering when applied to the algorithm prompting the researcher to do an investigation. It was revealed that fine tuning distance δ3 that determines the extent to which a given data point will be clustered helped improve the quality of cluster output. Even though the modification of distance δ3 significantly improved the solution quality and cluster output of the algorithm, results suggest that there is no difference between the population mean of the solutions obtained using the original and modified parameter setting for all data sets. This implies that using either the original or modified parameter setting will not have any effect towards obtaining the best global and local animal positions. Results also suggest that CDE-based clustering algorithm is better than CAB-density clustering algorithm for all data sets. Nevertheless, CAB-density clustering algorithm is still a good clustering algorithm because it has correctly identified the number of classes of some data sets more frequently in a thirty trial run with a much smaller standard deviation, a potential in clustering high dimensional data sets. Thus, the researcher recommends further investigation in the post-processing stage of the algorithm.

Keywords: clustering, metaheuristics, collective animal behavior algorithm, density-based clustering, multimodal optimization

Procedia PDF Downloads 230

Authors: Jin Koo

Abstract:

During the coronavirus pandemic, there has been a further increasing demand for computer-based tests (CBT), and now it has become an important test mode. The main purpose of this study is to investigate the comparability of student scores obtained from computerized-based formats of a standardized test in the two subject areas of reading and mathematics. Also, this study investigates whether there is an interaction effect between test modes of CBT and paper-based tests (PBT) and gender/ability level in each subject area. The test used in this study is a multiple-choice standardized test for students in grades 8-11. For this study, data were collected during four test administrations: 2015-16, 2017-18, and 2020-21. This research used a one-factor between-subjects ANOVA to compute the PBT and CBT groups’ test means for each subject area (reading and mathematics). Also, 2-factor between-subjects ANOVAs were conducted to investigate examinee characteristics: gender (male and female), ethnicity (African-American, Asian, Hispanic, multi-racial, and White), and ability level (low, average, and high-ability groups). The author found that students’ test scores in the two subject areas varied across CBT and PBT by gender and ability level, meaning that gender, ethnicity, and ability level were related to the score difference. These results will be discussed according to the current testing systems. In addition, this study’s results will open up to school teachers and test developers the possible influence that gender, ethnicity, and ability level have on a student’s score based on whether they take the CBT or PBT.

Keywords: ability level, computer-based, gender, paper-based, test

Procedia PDF Downloads 100

Authors: Md. Shams Razi Shopnil, Tanvir Imtiaz, Sabrina Mahjabin, Md. Sahadat Hossain

Abstract:

Saturated hydraulic conductivity is one of the most significant attributes of pavement base course. Determination of hydraulic conductivity is a routine procedure for regular aggregate base courses. However, in many cases, a cement-stabilized base course is used with compromised drainage ability. Traditional hydraulic conductivity testing procedure is a readily available option which leads to two consequential drawbacks, i.e., the time required for the specimen to be saturated and extruding the sample after completion of the laboratory test. To overcome these complications, this study aims at formulating an empirical approach to predicting hydraulic conductivity based on Unconfined Compressive Strength test results. To do so, this study comprises two separate experiments (Constant Head Permeability test and Unconfined Compressive Strength test) conducted concurrently on a specimen having the same physical credentials. Data obtained from the two experiments were then used to devise a correlation between hydraulic conductivity and unconfined compressive strength. This correlation in the form of a polynomial equation helps to predict the hydraulic conductivity of cement-treated pavement base course, bypassing the cumbrous process of traditional permeability and less commonly used horizontal permeability tests. The correlation was further corroborated by a different set of data, and it has been found that the derived polynomial equation is deemed to be a viable tool to predict hydraulic conductivity.

Keywords: hydraulic conductivity, unconfined compressive strength, recycled plastics, recycled concrete aggregates

Procedia PDF Downloads 90

Authors: Teh Raihana Nazirah Roslan, Siti Zulaiha Ibrahim, Sharmila Karim

Abstract:

A warrant is a financial contract that confers the right but not the obligation, to buy or sell a security at a certain price before expiration. The standard procedure to value equity warrants using call option pricing models such as the Black–Scholes model had been proven to contain many flaws, such as the assumption of constant interest rate and constant volatility. In fact, existing alternative models were found focusing more on demonstrating techniques for pricing, rather than empirical testing. Therefore, a mathematical model for pricing and analyzing equity warrants which comprises stochastic interest rate and stochastic volatility is essential to incorporate the dynamic relationships between the identified variables and illustrate the real market. Here, the aim is to develop dynamic pricing formulations for hybrid equity warrants by incorporating stochastic interest rates from the Cox-Ingersoll-Ross (CIR) model, along with stochastic volatility from the Heston model. The development of the model involves the derivations of stochastic differential equations that govern the model dynamics. The resulting equations which involve Cauchy problem and heat equations are then solved using partial differential equation approaches. The analytical pricing formulas obtained in this study comply with the form of analytical expressions embedded in the Black-Scholes model and other existing pricing models for equity warrants. This facilitates the practicality of this proposed formula for comparison purposes and further empirical study.

Keywords: Cox-Ingersoll-Ross model, equity warrants, Heston model, hybrid models, stochastic

Procedia PDF Downloads 129

Authors: Don Buddika Oshadi Malaweera, Lora Harris, Bruce Rathgeber, Chibuike C. Udenigwe, Kirsti Rouvinen-Watt

Abstract:

Fatty liver disease is among the three most severe health concerns for mink and believed to occur through the same mechanism as nursing sickness. In North America, nursing sickness affects about 45% of mink farms and in Canada, approximately 50,000 mink females is affected annually. Orotic acid (OA) plays a critical role in lipid metabolism and can increase hepatic lipids by enhancing Sterol regulatory element binding protein-1c expression and decreasing Carnitine palmitoyl transferase I activity. This study was conducted to identify particular pathways and regulatory control points involved in fatty liver development, and evaluate the effectiveness of arginine and bioactive peptides for prevention and treatment of fatty liver disease in mink. A total of 45 mink were used in 9 treatments. The experimental diets consisted of 1% OA, 2% L-arginine and 5% of whey protein hydrolysates. At the end of 10 days of experimental period, the mink were anaesthetized, sampled for blood and euthanized, samples were obtained for histological, biochemical and molecular assays. The blood samples will be analyzed for clinical chemistry and triacylglycerol. The liver samples will be analyzed for total lipid content and analyzed for 6 genes of interest involved in adipogenic transformation, ER stress, and liver inflammation.

Keywords: fatty liver, L-arginine, mink, orotic acid, whey protein hydrolysates

Procedia PDF Downloads 302

Authors: Sriram Kashyap Prasad, Ionut Florescu

Abstract:

This study models the intraday asset prices as driven by Markov process. This work identifies the latent states of the Hidden Markov model, using limit order book data (trades and quotes) to continuously estimate the states throughout the day. This work builds a trading strategy using estimated states to generate signals. The strategy utilizes current state to recalibrate buy/ sell levels and the transition between states to trigger stop-loss when adverse price movements occur. The proposed trading strategy is tested on the Stevens High Frequency Trading (SHIFT) platform. SHIFT is a highly realistic market simulator with functionalities for creating an artificial market simulation by deploying agents, trading strategies, distributing initial wealth, etc. In the implementation several assets on the NASDAQ exchange are used for testing. In comparison to a strategy with static buy/ sell levels, this study shows that the number of limit orders that get matched and executed can be increased. Executing limit orders earns rebates on NASDAQ. The system can capture jumps in the limit order book prices, provide dynamic buy/sell levels and trigger stop loss signals to improve the PnL (Profit and Loss) performance of the strategy.

Keywords: algorithmic trading, Hidden Markov model, high frequency trading, limit order book learning

Procedia PDF Downloads 151

Authors: Habib Alehossein, M. S. K. Fernando

Abstract:

Soil density depends on the volume of the voids and the proportion of the water and air in the voids. However, there is a limit to the contraction of the voids at any given compaction energy, whereby additional water is used to reduce the void volume further by lubricating the particles' frictional contacts. Hence, at an optimum moisture content and specific compaction energy, the density of unsaturated soil can be maximized where the void volume is minimum. However, when considering a full compaction curve and permutations and variations of all these components (soil, air, water, and energy), laboratory soil compaction tests can become expensive, time-consuming, and exhausting. Therefore, analytical methods constructed on a few test data can be developed and used to reduce such unnecessary efforts significantly. Concentrating on the compaction testing results, this study discusses the analytical modelling method developed for some fine-grained and coarse-grained soils of Queensland. Soil properties and characteristics, such as full functional compaction curves under various compaction energy conditions, were studied and developed for a few soil types. Using MATLAB, several generic analytical codes were created for this study, covering all possible compaction parameters and results as they occur in a soil mechanics lab. These MATLAB codes produce a family of curves to determine the relationships between the density, moisture content, void ratio, saturation, and compaction energy.

Keywords: analytical, MATLAB, modelling, compaction curve, void ratio, saturation, moisture content

Procedia PDF Downloads 90

Authors: Anthony Townsend, Robyn Fasser

Abstract:

While complete objectivity is a desirable scientific position from which to conduct a care and contact evaluation (CCE), it is precisely the recognition that we are inherently incapable of operating objectively that is the foundation of ethical practice and skilled assessment. Drawing upon recent research from Daniel Kahneman (2021) on the differences between noise and bias, as well as different inherent biases collectively termed “The Elephant in the Brain” by Kevin Simler and Robin Hanson (2019) from Oxford University, this presentation addresses both the various ways in which our judgments, perceptions and even procedures can be distorted and contaminated while conducting a CCE, but also considers the value of second order cybernetics and the psychodynamic concept of ‘ambivalence’ as a conceptual basis to inform our assessment methodologies to limit such errors or at least better identify them. Both a conceptual framework for ambivalence, our higher-order capacity to allow for the convergence and consideration of multiple emotional experiences and cognitive perceptions to inform our reasoning, and a practical methodology for assessment relying on data triangulation, Bayesian inference and hypothesis testing is presented as a means of promoting ethical practice for health care professionals conducting CCEs. An emphasis on widening awareness and perspective, limiting ‘splitting’, is demonstrated both in how this form of emotional processing plays out in alienating dynamics in families as well as the assessment thereof. In addressing this concept, this presentation aims to illuminate the value of ambivalence as foundational to ethical practice for assessors.

Keywords: ambivalence, forensic, psychology, noise, bias, ethics

Procedia PDF Downloads 86

Authors: Abdalaziz M. Alsalhabi, Loai M. Alowa

Abstract:

This paper investigates Weld Rejection Rate (WRR) limits and tracer effects in construction projects, with a specific focus on a Gas Plant Project, a mega-project held by Saudi Aramco (SA) in Saudi Arabia. The study included a comprehensive examination of various factors impacting WRR limits. It commenced by comparing the Company practices with ASME standards, followed by an in-depth analysis of both weekly and cumulative projects' historical WRR data, evaluation of Radiographic Testing (RT) reports for rejected welds, and proposal of mitigation methods to eliminate future rejections. Additionally, the study revealed the causes of fluctuation in WRR data and benchmarked with the industry practices. Furthermore, a case study was conducted to explore the impact of tracers on WRR, providing insights into their influence on the welding process. This paper aims to achieve three primary objectives. Firstly, it seeks to validate the existing practices of WRR limits and advocate for their inclusion within relevant International Industry Standards. Secondly, it aims to validate the effectiveness of the WRR formula that incorporates tracer effects, ensuring its reliability in assessing weld quality. Lastly, this study aims to identify opportunities for process improvement in WRR control, with the ultimate goal of enhancing project processes and ensuring the integrity, safety, and efficiency of constructed assets.

Keywords: weld rejection rate, weld repair rate in joint and linear basis, tracers effects, construction projects

Procedia PDF Downloads 41

Authors: Gali Moritz, Jacqueline H. Becker, Jyoti V. Ankam, Kimberly Arcoleo, Matthew Wysocki, Roee Holtzer, Juan Wisnivesky, Paula J. Busse, Alex D. Federman, Sunit P. Jariwala, Jonathan M. Feldman

Abstract:

Objective: Cognitive impairment (CI), whose incidence is greater among ethnic/racial minorities, is a significant barrier to asthma self-management (SM) behaviors and outcomes in older adults. The aim of this study was to examine the relationships between CI, assessed using the Montreal Cognitive Assessment (MoCA), and asthma SM behaviors and outcomes in a sample of predominantly Black and Hispanic participants. Additionally, we evaluated whether using two different MoCA cutoff scores influenced the association between CI and study outcomes. Methods: Baseline cross-sectional data were extracted from a longitudinal study of older adults with asthma (N=165) age≥ 60 years and used for analysis. Cognition was assessed using the MoCA. Asthma control, asthma-related quality of life (QOL), inhaled corticosteroid (ICS) dosing, and ICS adherence were assessed using self-report. The inhaler technique was observed and rated. Results: Using established MoCA cutoff scores of 23 and 26 yielded 45% and 74% CI rates, respectively. CI, defined using the 23 cutoff score, was significantly associated with worse asthma control (p=.04) and worse ICS adherence (p=.01). With a cutoff score of 26, only asthma-related QOL was significantly associated with CI (p=.03). Race/ethnicity and education did not moderate the relationships between CI and asthma SM behaviors and outcomes. Conclusions: CI in older adults with asthma is associated with important clinical outcomes, but this relationship is influenced by the cutoff score used to define CI.

Keywords: cognition, respiratory, elderly, testing, adherence, validity

Procedia PDF Downloads 80

Authors: Arvind Mittal, Rajesh Gupta

Abstract:

Influence of heat input on the micro structure and mechanical properties of shield metal arc welded of duplex stainless steel UNSNO.S-31803 has been investigated. Three heat input combinations designated as low heat (0.675 KJ/mm), medium heat (0.860 KJ/mm) and high heat (1.094 KJ/mm) and weld joints made using these combinations were subjected to micro structural evaluations and tensile and impact testing so as to analyze the effect of thermal arc energy on the micro structure and mechanical properties of these joints. The result of this investigation shows that the joints made using low heat input exhibited higher tensile strength than those welded with medium and high heat input. Heat affected zone of welded joint made with medium heat input has austenitic ferritic grain structure with some patchy austenite provide high toughness. Significant grain coarsening was observed in the heat affected zone (HAZ) of medium and high heat input welded joints, whereas low heat input welded joint shows the fine grain structure in the heat affected zone with small amount of dendritic formation and equiaxed grain structure where inner zone indicates slowly cooled grains in the direction of heat dissipation. This is the main reason for the observable changes of tensile properties of weld joints welded with different arc energy inputs.

Keywords: microstructure, mechanical properties, shield metal arc welded, duplex stainless steel

Procedia PDF Downloads 279

Authors: Natalie M. Khazaal

Abstract:

The effects of the civil war on Lebanese women have been challenging to conceptualize. For some, war is a liberating and empowering force for women, while for others it is one that subjugates women and disempowers them in new ways. Scholars have explored the impact on the Lebanese civil war (1975-1990) on women in the fields of labor history, political activism and literary production. In all these arenas, women’s role and visibility were contested and negotiated in diverse ways. But probably the most visible arena where this contestation took place was television. Dramatized entertainment series were crucial sites where fictional women battled out the gender question, and which reflected and participated in the negotiations of gender politics. Even more stunningly, actual television stations became part of this battle through the plots and portrayals of women that they created. The state-backed Tele-Liban (TL) peddled patriarchal articulations of gender that directly competed with the edgy vision of liberated, independent women on the pirate Lebanese Broadcasting Corporation (LBC). This presentation explores how LBC used gender to distinguish its brand against the retrograde TL programing. Television series are an important medium for creating, testing and reenacting gender politics. They are even more consequential in another way. They are the sites where a dramatic shift in the relationship between Arab television and Arab publics—from benign neglect of public concerns towards engagement with audiences—took place for the first time. As this shift is at the heart of why Arab media was seen as a participant in the Arab uprisings, it is important to explore the roots of the shift in the dramas and comedy series of the mid-1980s Lebanese television. This presentation argues that television battles over gender were consequential and need serious consideration as sites of unexpected meaning.

Keywords: gender, Lebanon, television, war, women

Procedia PDF Downloads 637

Authors: P. Gao, Z. Q. Li, Y. G. Jin

Abstract:

In the past 10 years, computers and cellphones have become one of the most important factors in our lives, and one which has a tremendously negative impact on our muscles. Muscle tension may be one of the causes of sleep disturbance. Tension in the shoulders and neck can affect blood circulation to the muscles. This research uses a dry needling treatment to reduce muscle tension in order to determine if the strain in the head and shoulders can influence sleep duration. All 38 patients taking part in the testing suffered from tinnitus and have been experiencing disturbed sleep for at least one to five years. Even after undergoing drug therapy treatments and traditional acupuncture therapies, their sleep disturbances have not shown any improvement. After five to 10 dry needling treatments, 24 of the patients reported an improvement in their sleep duration. Five patients considered themselves to be completely recovered, while 12 patients experienced no improvement. This study investigated these pathogenic and therapeutic problems. The standard treatment for sleep disturbances is drug-based therapy; the results of most standard treatments are unfortunately negative. The result of this clinical research has demonstrated that: The possible cause of sleep disturbance for a lot of patients is the result of tensions in the neck and shoulder muscles. Blood circulation to those muscles is also influenced by the duration of sleep. Hypertonic neck and shoulder muscles are considered to impact sleeping patterns and lead to disturbed sleep. Poor posture, often adopted while speaking on the phone, is one of the main causes of hypertonic neck and shoulder muscle problems. The dry needling treatment specifically focuses on the release of muscle tension.

Keywords: dry needling, muscle tension, sleep duration, hypertonic muscles

Procedia PDF Downloads 245

Authors: Andrej Golowin, Viktor Denk, Axel Riepe

Abstract:

Solid fan blades and discs in aero engines are subjected to high combined low and high cycle fatigue loads especially around the contact areas between blade and disc. Therefore, special coatings (e.g. dry film lubricant) and surface treatments (e.g. shot peening or laser shock peening) are applied to increase the strength with respect to combined cyclic fatigue and fretting fatigue, but also to improve damage tolerance capability. The traditional deterministic damage tolerance assessment based on fracture mechanics analysis, which treats service damage as an initial crack, often gives overly conservative results especially in the presence of vibratory stresses. A probabilistic damage tolerance methodology using crack initiation data has been developed for fan discs exposed to relatively high vibratory stresses in cross- and tail-wind conditions at certain resonance speeds for limited time periods. This Monte-Carlo based method uses a damage databank from similar designs, measured vibration levels at typical aircraft operations and wind conditions and experimental crack initiation data derived from testing of artificially damaged specimens with representative surface treatment under combined fatigue conditions. The proposed methodology leads to a more realistic prediction of the minimum damage tolerance life for the most critical locations applicable to modern fan disc designs.

Keywords: combined fatigue, damage tolerance, engine, surface treatment

Procedia PDF Downloads 496

Authors: Tannistha Dasgupta

Abstract:

This study explores the aspects of second language (L2) spoken fluency that are related to L2 linguistic knowledge and processing skill. It draws on Levelt’s ‘blueprint’ of the L2 speaker which discusses the cognitive issues underlying the act of speaking. However, L2 speaking assessments have largely neglected the underlying mechanism involved in language production; emphasis is given on the relationship between subjective ratings of L2 speech sample and objectively measured aspects of fluency. Hence, in this study, the relation between L2 linguistic knowledge and processing skill i.e. Cognitive Fluency (CF), and objectively measurable aspects of L2 spoken fluency i.e. Utterance Fluency (UF) is examined. The participants of the study are L2 learners of English, studying at high school level in Hyderabad, India. 50 participants with intermediate level of proficiency in English performed several lexical retrieval tasks and attention-shifting tasks to measure CF, and 8 oral tasks to measure UF. Each aspect of UF (speed, pause, and repair) were measured against the scores of CF to find out those aspects of UF which are reliable indicators of CF. Quantitative analysis of the data shows that among the three aspects of UF; speed is the best predictor of CF, and pause is weakly related to CF. The study suggests that including the speed aspect of UF could make L2 fluency assessment more reliable, valid, and objective. Thus, incorporating the assessment of psycholinguistic mechanisms into L2 spoken fluency testing, could result in fairer evaluation.

Keywords: attention-shifting, cognitive fluency, lexical retrieval, utterance fluency

Procedia PDF Downloads 711