Search results for: partial feedback linearization
2132 Analytical Authentication of Butter Using Fourier Transform Infrared Spectroscopy Coupled with Chemometrics
Authors: M. Bodner, M. Scampicchio
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Fourier Transform Infrared (FT-IR) spectroscopy coupled with chemometrics was used to distinguish between butter samples and non-butter samples. Further, quantification of the content of margarine in adulterated butter samples was investigated. Fingerprinting region (1400-800 cm–1) was used to develop unsupervised pattern recognition (Principal Component Analysis, PCA), supervised modeling (Soft Independent Modelling by Class Analogy, SIMCA), classification (Partial Least Squares Discriminant Analysis, PLS-DA) and regression (Partial Least Squares Regression, PLS-R) models. PCA of the fingerprinting region shows a clustering of the two sample types. All samples were classified in their rightful class by SIMCA approach; however, nine adulterated samples (between 1% and 30% w/w of margarine) were classified as belonging both at the butter class and at the non-butter one. In the two-class PLS-DA model’s (R2 = 0.73, RMSEP, Root Mean Square Error of Prediction = 0.26% w/w) sensitivity was 71.4% and Positive Predictive Value (PPV) 100%. Its threshold was calculated at 7% w/w of margarine in adulterated butter samples. Finally, PLS-R model (R2 = 0.84, RMSEP = 16.54%) was developed. PLS-DA was a suitable classification tool and PLS-R a proper quantification approach. Results demonstrate that FT-IR spectroscopy combined with PLS-R can be used as a rapid, simple and safe method to identify pure butter samples from adulterated ones and to determine the grade of adulteration of margarine in butter samples.Keywords: adulterated butter, margarine, PCA, PLS-DA, PLS-R, SIMCA
Procedia PDF Downloads 1472131 Perceptions of College Students on Whether an Intelligent Tutoring System Is a Tutor
Authors: Michael Smalenberger
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Intelligent tutoring systems (ITS) are computer-based platforms which can incorporate artificial intelligence to provide step-by-step guidance as students practice problem-solving skills. ITS can replicate the benefits of one-on-one tutoring, foster transactivity in collaborative environments, and lead to substantial learning gains when used to supplement the instruction of a teacher or when used as the sole method of instruction. Developments improving the ease of ITS creation have recently increased their proliferation, leading many K-12 schools and institutions of higher education in the United States to regularly use ITS within classrooms. We investigated how students perceive their experience using an ITS. In this study, 111 undergraduate students used an ITS in a college-level introductory statistics course and were subsequently asked for feedback on their experience. Results show that their perceptions were generally favorable of the ITS, and most would seek to use an ITS both for STEM and non-STEM courses in the future. Along with detailed transaction-level data, this feedback also provides insights on the design of user-friendly interfaces, guidance on accessibility for students with impairments, the sequencing of exercises, students’ expectation of achievement, and comparisons to other tutoring experiences. We discuss how these findings are important for the creation, implementation, and evaluation of ITS as a mode and method of teaching and learning.Keywords: college statistics course, intelligent tutoring systems, in vivo study, student perceptions of tutoring
Procedia PDF Downloads 1022130 Numerical Study of Trailing Edge Serrations on a Wells Turbine
Authors: Abdullah S. AlKhalifa, Mohammad Nasim Uddin, Michael Atkinson
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The primary objective of this investigation is to explore the aerodynamic impact of adding trailing edge serrations to a Wells turbine. The baseline turbine consists of eight blades with NACA 0015 airfoils. The blade chord length was 0.125 m, and the span was 0.100 m. Two modified NACA 0015 serrated configurations were studied: 1) full-span and 2) partial span serrations covering the trailing edge from hub to tip. Numerical simulations were carried out by solving the three-dimensional, incompressible steady-state Reynolds Averaged Navier-Stokes (RANS) equations using the k-ω SST turbulence model in ANSYS™ (CFX). The aerodynamic performance of the modified Wells turbine to the baseline was made by comparing non-dimensional parameters of torque coefficient, pressure drop coefficient, and turbine efficiency. A comparison of the surface limiting streamlines was performed to analyze the flow topology of the turbine blades. The trailing edge serrations generated a substantial change in surface pressure and effectively reduced the separated flow region, thus improving efficiency in most cases. As a result, the average efficiency increased across the range of simulated flow coefficients.Keywords: renewable energy, trailing edge serrations, Wells turbine, partial serration
Procedia PDF Downloads 1032129 The Chromitites of the Collo Ultramafic Rocks (NE Algeria): Two Generations Evidenced From Petrological, Mineralogical and Isotopic Studies
Authors: Rabah Laouar, Yahia Boudra, Adel Satouh, Adrian Boyce
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The ultramafic rocks of the Collo region crop out as « stratified » masses that cross-cut older metamorphic formation of the basement. These rocks are mainly peridotites and serpentinites. The peridotites are composed of olivine, orthopyroxene, clinopyroxene and spinel (chromite). The chemical composition of these lherzolites show a magnesian character with high MgO contents (34.4 to 37.5%), high Cr (0.14 to 0.27%), Ni (0.14 to 0.26%) and Co (34 to 133 ppm) and low CaO and Al₂O₃ (0.02 to 2.2 and 0.5 to 2.8 % respectively). They represent a residue (restite) of a mantle magmas partial melting. The chromite which represents about 2 to 3% of the rock is a ubiquitous mineral and shows two different generations: primary idiomorphic millimetric crystals and secondary very fine, xenomorphic and interstitial aggregates. The primary chromites are alumino-ferro-magnesian crystals. They show high Al₂O₃ (25.77% to 27.36%) and MgO (10.70% to 13.36%). Cr# (100*Cr/ (Al+Cr)) varies between 45 and 48, and Mg# (100*Mg/Mg+Fe₂+) varies between 49 and 59. On the other hand, the secondary interstitial grains are iron-rich chromites; they show low Al₂O₃ (4.67% to 9.54%) and MgO (4.60% to 4.65%). Cr# is relatively high (77 to 88) whereas Mg# show relatively low values, varying between 22 and 25. Oxygen isotopic composition of both types of chromites is consistent with their derivation from a mantle source (ð¹⁸O vary between +3.9 and +5.2‰), though a contribution of ¹⁶O-rich component to the secondary chromites is not ruled out.Keywords: peridotites, serpentinites, chromite, partial melting, collo, Algeria
Procedia PDF Downloads 922128 Similar Correlation of Meat and Sugar to Global Obesity Prevalence
Authors: Wenpeng You, Maciej Henneberg
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Background: Sugar consumption has been overwhelmingly advocated as a major dietary offender to obesity prevalence. Meat intake has been hypothesized as an obesity contributor in previous publications, but a moderate amount of meat to be included in our daily diet still has been suggested in many dietary guidelines. Comparable sugar and meat exposure data were obtained to assess the difference in relationships between the two major food groups and obesity prevalence at population level. Methods: Population level estimates of obesity and overweight rates, per capita per day exposure of major food groups (meat, sugar, starch crops, fibers, fats and fruits) and total calories, per capita per year GDP, urbanization and physical inactivity prevalence rate were extracted and matched for statistical analysis. Correlation coefficient (Pearson and partial) comparisons with Fisher’s r-to-z transformation and β range (β ± 2 SE) and overlapping in multiple linear regression (Enter and Stepwise) were used to examine potential differences in the relationships between obesity prevalence and sugar exposure and meat exposure respectively. Results: Pearson and partial correlations (controlled for total calories, physical inactivity prevalence, GDP and urbanization) analyses revealed that sugar and meat exposures correlated to obesity and overweight prevalence significantly. Fisher's r-to-z transformation did not show statistically significant difference in Pearson correlation coefficients (z=-0.53, p=0.5961) or partial correlation coefficients (z=-0.04, p=0.9681) between obesity prevalence and both sugar exposure and meat exposure. Both Enter and Stepwise models in multiple linear regression analysis showed that sugar and meat exposure were most significant predictors of obesity prevalence. Great β range overlapping in the Enter (0.289-0.573) and Stepwise (0.294-0.582) models indicated statistically sugar and meat exposure correlated to obesity without significant difference. Conclusion: Worldwide sugar and meat exposure correlated to obesity prevalence at the same extent. Like sugar, minimal meat exposure should also be suggested in the dietary guidelines.Keywords: meat, sugar, obesity, energy surplus, meat protein, fats, insulin resistance
Procedia PDF Downloads 3062127 Emotion Mining and Attribute Selection for Actionable Recommendations to Improve Customer Satisfaction
Authors: Jaishree Ranganathan, Poonam Rajurkar, Angelina A. Tzacheva, Zbigniew W. Ras
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In today’s world, business often depends on the customer feedback and reviews. Sentiment analysis helps identify and extract information about the sentiment or emotion of the of the topic or document. Attribute selection is a challenging problem, especially with large datasets in actionable pattern mining algorithms. Action Rule Mining is one of the methods to discover actionable patterns from data. Action Rules are rules that help describe specific actions to be made in the form of conditions that help achieve the desired outcome. The rules help to change from any undesirable or negative state to a more desirable or positive state. In this paper, we present a Lexicon based weighted scheme approach to identify emotions from customer feedback data in the area of manufacturing business. Also, we use Rough sets and explore the attribute selection method for large scale datasets. Then we apply Actionable pattern mining to extract possible emotion change recommendations. This kind of recommendations help business analyst to improve their customer service which leads to customer satisfaction and increase sales revenue.Keywords: actionable pattern discovery, attribute selection, business data, data mining, emotion
Procedia PDF Downloads 2002126 Performance Analysis of PAPR Reduction in OFDM Systems based on Partial Transmit Sequence (PTS) Technique
Authors: Alcardo Alex Barakabitze, Tan Xiaoheng
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Orthogonal Frequency Division Multiplexing (OFDM) is a special case of Multi-Carrier Modulation (MCM) technique which transmits a stream of data over a number of lower data rate subcarriers. OFDM splits the total transmission bandwidth into a number of orthogonal and non-overlapping subcarriers and transmit the collection of bits called symbols in parallel using these subcarriers. This paper explores the Peak to Average Power Reduction (PAPR) using the Partial Transmit Sequence technique. We provide the distribution analysis and the basics of OFDM signals and then show how the PAPR increases as the number of subcarriers increases. We provide the performance analysis of CCDF and PAPR expressed in decibels through MATLAB simulations. The simulation results show that, in PTS technique, the performance of PAPR reduction in OFDM systems improves significantly as the number of sub-blocks increases. However, by keeping the same number of sub-blocks variation, oversampling factor and the number of OFDM blocks’ iteration for generating the CCDF, the OFDM systems with 128 subcarriers have an improved performance in PAPR reduction compared to OFDM systems with 256, 512 or >512 subcarriers.Keywords: OFDM, peak to average power reduction (PAPR), bit error rate (BER), subcarriers, wireless communications
Procedia PDF Downloads 5152125 Improving Student Programming Skills in Introductory Computer and Data Science Courses Using Generative AI
Authors: Genady Grabarnik, Serge Yaskolko
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Generative Artificial Intelligence (AI) has significantly expanded its applicability with the incorporation of Large Language Models (LLMs) and become a technology with promise to automate some areas that were very difficult to automate before. The paper describes the introduction of generative Artificial Intelligence into Introductory Computer and Data Science courses and analysis of effect of such introduction. The generative Artificial Intelligence is incorporated in the educational process two-fold: For the instructors, we create templates of prompts for generation of tasks, and grading of the students work, including feedback on the submitted assignments. For the students, we introduce them to basic prompt engineering, which in turn will be used for generation of test cases based on description of the problems, generating code snippets for the single block complexity programming, and partitioning into such blocks of an average size complexity programming. The above-mentioned classes are run using Large Language Models, and feedback from instructors and students and courses’ outcomes are collected. The analysis shows statistically significant positive effect and preference of both stakeholders.Keywords: introductory computer and data science education, generative AI, large language models, application of LLMS to computer and data science education
Procedia PDF Downloads 582124 GUI Design of Mathematical Model of Cardiovascular-Respiratory System
Authors: Ntaganda J.M., Maniraguha J.D., Mukeshimana S., Harelimana D, Bizimungu T., Ruataganda E.
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This paper presents the design of Graphic User Interface (GUI) in Matlab as interaction tool between human and machine. The designed GUI can be used by medical doctors and other experts particularly the physiologists. Matlab packages and estimated parameters of the mathematical model of cardiovascular-respiratory system developed in Rwandan context are used in GUI. The ordinary differential equations (ODE’s) govern a mathematical model in designing GUI in Matlab and a window that sets model estimated parameters and the measured parameters by any user. For healthy subject, these measured parameters include heart rate, systolic blood and diastolic blood pressure, partial pressure of oxygen in arterial blood, partial pressure of carbon dioxide in arterial blood, concentration of bound and dissolved oxygen in the mixed venous blood entering the lungs, and concentration of bound and dissolved carbon dioxide in the mixed venous blood entering the lungs. The results of numerical test give a consistent appearance as empirically known results.Keywords: Graphic User Interface, mathematical model, cardiovascur-respiratory system, walking physical activity, blood pressure, oxygen
Procedia PDF Downloads 1192123 The Influence of Partial Replacement of Hydrated Lime by Pozzolans on Properties of Lime Mortars
Authors: Przemyslaw Brzyski, Stanislaw Fic
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Hydrated lime, because of the life cycle (return to its natural form as a result of the setting and hardening) has a positive environmental impact. The lime binder is used in mortars. Lime is a slow setting binder with low mechanical properties. The aim of the study was to evaluate the possibility of improving the properties of the lime binder by using different pozzolanic materials as partial replacement of hydrated lime binder. Pozzolan materials are the natural or industrial waste, so do not affect the environmental impact of the lime binder. The following laboratory tests were performed: the analysis of the physical characteristics of the tested samples of lime mortars (bulk density, porosity), flexural and compressive strength, water absorption and the capillary rise of samples and consistency of fresh mortars. As a partial replacement of hydrated lime (in the amount of 10%, 20%, 30% by weight of lime) a metakaolin, silica fume, and zeolite were used. The shortest setting and hardening time showed mortars with the addition of metakaolin. All additives noticeably improved strength characteristic of lime mortars. With the increase in the amount of additive, the increase in strength was also observed. The highest flexural strength was obtained by using the addition of metakaolin in an amount of 20% by weight of lime (2.08 MPa). The highest compressive strength was obtained by using also the addition of metakaolin but in an amount of 30% by weight of lime (9.43 MPa). The addition of pozzolan caused an increase in the mortar tightness which contributed to the limitation of absorbability. Due to the different surface area, pozzolanic additives affected the consistency of fresh mortars. Initial consistency was assumed as plastic. Only the addition of silica fume an amount of 20 and 30% by weight of lime changed the consistency to the thick-plastic. The conducted study demonstrated the possibility of applying lime mortar with satisfactory properties. The features of lime mortars do not differ significantly from cement-based mortar properties and show a lower environmental impact due to CO₂ absorption during lime hardening. Taking into consideration the setting time, strength and consistency, the best results can be obtained with metakaolin addition to the lime mortar.Keywords: lime, binder, mortar, pozzolan, properties
Procedia PDF Downloads 1942122 Understanding the Lived Experiences of Children and Young People Using Client Preference Tools in Mental Health Therapy: A Systematic Literature Review
Authors: Charlotte Zamani
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Children's and young people’s (CYP’s) perspectives on using client preference tools are central to understanding youth mental health therapy engagement. This systematic literature review attempts to understand the meanings of CYP using preference tools that may allow greater connection with the therapeutic process. Following a systematic search using PRISMA guidelines, seven studies were identified that reported qualitative feedback on preferred treatment options or activities within therapy. The data were analysed using interpretative phenomenological analysis (IPA). Three group experiential themes were found: ‘Tailor my support’, ‘My autonomy leads to greater engagement’ and ‘Preferences facilitate my authentic self’. CYP is broadly divided into those who thrive in decision-making and those who require more support. Being offered a choice in therapy delivery provides easier access and means more freedom for CYP. Preferences in therapy appeared to enable greater self-knowledge and a deeper connection to the therapeutic process. The therapist is integral in using preference tools in therapy. Youth feedback is currently limited, yet essential and ethical in order to understand critical factors of CYP engagement and for future research.Keywords: child and adolescent, client preferences, mental health therapy, qualitative
Procedia PDF Downloads 132121 Transportation Mode Classification Using GPS Coordinates and Recurrent Neural Networks
Authors: Taylor Kolody, Farkhund Iqbal, Rabia Batool, Benjamin Fung, Mohammed Hussaeni, Saiqa Aleem
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The rising threat of climate change has led to an increase in public awareness and care about our collective and individual environmental impact. A key component of this impact is our use of cars and other polluting forms of transportation, but it is often difficult for an individual to know how severe this impact is. While there are applications that offer this feedback, they require manual entry of what transportation mode was used for a given trip, which can be burdensome. In order to alleviate this shortcoming, a data from the 2016 TRIPlab datasets has been used to train a variety of machine learning models to automatically recognize the mode of transportation. The accuracy of 89.6% is achieved using single deep neural network model with Gated Recurrent Unit (GRU) architecture applied directly to trip data points over 4 primary classes, namely walking, public transit, car, and bike. These results are comparable in accuracy to results achieved by others using ensemble methods and require far less computation when classifying new trips. The lack of trip context data, e.g., bus routes, bike paths, etc., and the need for only a single set of weights make this an appropriate methodology for applications hoping to reach a broad demographic and have responsive feedback.Keywords: classification, gated recurrent unit, recurrent neural network, transportation
Procedia PDF Downloads 1382120 Optimizing Fire Suppression Time in Buildings by Forming a Fire Feedback Loop
Authors: Zhdanova A. O., Volkov R. S., Kuznetsov G. V., Strizhak P. A.
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Fires in different types of facilities are a serious problem worldwide.It is still an unaccomplished science and technology objective to establish the minimum number and type of sensors in automatic systems of compartment fire suppression which would turn the fire-extinguishing agent spraying on and off in real time depending on the state of the fire, minimize the amount of agent applied, delay time in fire suppression and system response, as well as the time of combustion suppression. Based on the results of experimental studies, the conclusion was made that it is reasonable to use a gas analysis system and heat sensors (in the event of their prior activation) to determine the effectiveness of fire suppression (fire-extinguishing composition interacts with the fire). Thus, the concentration of CO in the interaction of the firefighting liquid with the fire increases to 0.7–1.2%, which indicates a slowdown in the flame combustion, and heat sensors stop responding at a gas medium temperature below 80 ºC, which shows a gradual decrease in the heat release from the fire. The evidence from this study suggests that the information received from the video recording equipment (video camera) should be used in real time as an additional parameter confirming fire suppression. Research was supported by Russian Science Foundation (project No 21-19-00009, https://rscf.ru/en/project/21-19-00009/).Keywords: compartment fires, fire suppression, continuous control of fire behavior, feedback systems
Procedia PDF Downloads 1302119 Wearable Interface for Telepresence in Robotics
Authors: Uriel Martinez-Hernandez, Luke W. Boorman, Hamideh Kerdegari, Tony J. Prescott
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In this paper, we present architecture for the study of telepresence, immersion and human-robot interaction. The architecture is built around a wearable interface, developed here, that provides the human with visual, audio and tactile feedback from a remote location. We have chosen to interface the system with the iCub humanoid robot, as it mimics many human sensory modalities, such as vision, with gaze control and tactile feedback. This allows for a straightforward integration of multiple sensory modalities, but also offers a more complete immersion experience for the human. These systems are integrated, controlled and synchronised by an architecture developed for telepresence and human-robot interaction. Our wearable interface allows human participants to observe and explore a remote location, while also being able to communicate verbally with humans located in the remote environment. Our approach has been tested from local, domestic and business venues, using wired, wireless and Internet based connections. This has involved the implementation of data compression to maintain data quality to improve the immersion experience. Initial testing has shown the wearable interface to be robust. The system will endow humans with the ability to explore and interact with other humans at remote locations using multiple sensing modalities.Keywords: telepresence, telerobotics, human-robot interaction, virtual reality
Procedia PDF Downloads 2902118 Engaging Students in Learning through Visual Demonstration Models in Engineering Education
Authors: Afsha Shaikh, Mohammed Azizur Rahman, Ibrahim Hassan, Mayur Pal
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Student engagement in learning is instantly affected by the sources of learning methods available for them, such as videos showing the applications of the concept or showing a practical demonstration. Specific to the engineering discipline, there exist enormous challenging concepts that can be simplified when they are connected to real-world scenarios. For this study, the concept of heat exchangers was used as it is a part of multidisciplinary engineering fields. To make the learning experience enjoyable and impactful, 3-D printed heat exchanger models were created for students to use while working on in-class activities and assignments. Students were encouraged to use the 3-D printed heat exchanger models to enhance their understanding of theoretical concepts associated with its applications. To assess the effectiveness of the method, feedback was received by students pursuing undergraduate engineering via an anonymous electronic survey. To make the feedback more realistic, unbiased, and genuine, students spent nearly two to three weeks using the models in their in-class assignments. The impact of these tools on their learning was assessed through their performance in their ungraded assignments as well as their interactive discussions with peers. ‘Having to apply the theory learned in class whilst discussing with peers on a class assignment creates a relaxed and stress-free learning environment in classrooms’; this feedback was received by more than half the students who took the survey and found 3-D models of heat exchanger very easy to use. Amongst many ways to enhance learning and make students more engaged through interactive models, this study sheds light on the importance of physical tools that help create a lasting mental representation in the minds of students. Moreover, in this technologically enhanced era, the concept of augmented reality was considered in this research. E-drawings application was recommended to enhance the vision of engineering students so they can see multiple views of the detailed 3-D models and cut through its different sides and angles to visualize it properly. E-drawings could be the next tool to implement in classrooms to enhance students’ understanding of engineering concepts.Keywords: student engagement, life-long-learning, visual demonstration, 3-D printed models, engineering education
Procedia PDF Downloads 1162117 Image Segmentation Using Active Contours Based on Anisotropic Diffusion
Authors: Shafiullah Soomro
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Active contour is one of the image segmentation techniques and its goal is to capture required object boundaries within an image. In this paper, we propose a novel image segmentation method by using an active contour method based on anisotropic diffusion feature enhancement technique. The traditional active contour methods use only pixel information to perform segmentation, which produces inaccurate results when an image has some noise or complex background. We use Perona and Malik diffusion scheme for feature enhancement, which sharpens the object boundaries and blurs the background variations. Our main contribution is the formulation of a new SPF (signed pressure force) function, which uses global intensity information across the regions. By minimizing an energy function using partial differential framework the proposed method captures semantically meaningful boundaries instead of catching uninterested regions. Finally, we use a Gaussian kernel which eliminates the problem of reinitialization in level set function. We use several synthetic and real images from different modalities to validate the performance of the proposed method. In the experimental section, we have found the proposed method performance is better qualitatively and quantitatively and yield results with higher accuracy compared to other state-of-the-art methods.Keywords: active contours, anisotropic diffusion, level-set, partial differential equations
Procedia PDF Downloads 1622116 Worst-Case Load Shedding in Electric Power Networks
Authors: Fu Lin
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We consider the worst-case load-shedding problem in electric power networks where a number of transmission lines are to be taken out of service. The objective is to identify a prespecified number of line outages that lead to the maximum interruption of power generation and load at the transmission level, subject to the active power-flow model, the load and generation capacity of the buses, and the phase-angle limit across the transmission lines. For this nonlinear model with binary constraints, we show that all decision variables are separable except for the nonlinear power-flow equations. We develop an iterative decomposition algorithm, which converts the worst-case load shedding problem into a sequence of small subproblems. We show that the subproblems are either convex problems that can be solved efficiently or nonconvex problems that have closed-form solutions. Consequently, our approach is scalable for large networks. Furthermore, we prove the convergence of our algorithm to a critical point, and the objective value is guaranteed to decrease throughout the iterations. Numerical experiments with IEEE test cases demonstrate the effectiveness of the developed approach.Keywords: load shedding, power system, proximal alternating linearization method, vulnerability analysis
Procedia PDF Downloads 1412115 An Investigation on Fresh and Hardened Properties of Concrete While Using Polyethylene Terephthalate (PET) as Aggregate
Authors: Md. Jahidul Islam, A. K. M. Rakinul Islam, M. Salamah Meherier
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This study investigates the suitability of using plastic, such as polyethylene terephthalate (PET), as a partial replacement of natural coarse and fine aggregates (for example, brick chips and natural sand) to produce lightweight concrete for load bearing structural members. The plastic coarse aggregate (PCA) and plastic fine aggregate (PFA) were produced from melted polyethylene terephthalate (PET) bottles. Tests were conducted using three different water–cement (w/c) ratios, such as 0.42, 0.48, and 0.57, where PCA and PFA were used as 50% replacement of coarse and fine aggregate respectively. Fresh and hardened properties of concrete have been compared for natural aggregate concrete (NAC), PCA concrete (PCC) and PFA concrete (PFC). The compressive strength of concrete at 28 days varied with the water–cement ratio for both the PCC and PFC. Between PCC and PFC, PFA concrete showed the highest compressive strength (23.7 MPa) at 0.42 w/c ratio and also the lowest compressive strength (13.7 MPa) at 0.57 w/c ratio. Significant reduction in concrete density was mostly observed for PCC samples, ranging between 1977–1924 kg/m³. With the increase in water–cement ratio PCC achieved higher workability compare to both NAC and PFC. It was found that both the PCA and PFA contained concrete achieved the required compressive strength to be used for structural purpose as partial replacement of the natural aggregate; but to obtain the desired lower density as lightweight concrete the PCA is most suited.Keywords: polyethylene terephthalate, plastic aggregate, concrete, fresh and hardened properties
Procedia PDF Downloads 4412114 Mediating Role of Social Responsibility on the Relationship between Consumer Awareness of Green Marketing and Purchase Intentions
Authors: Norazah Mohd Suki, Norbayah Mohd Suki
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This research aims to examine the influence of mediating effect of corporate social responsibility on the relationship between consumer awareness of green marketing and purchase intentions in the retail setting. Data from 200 valid questionnaires was analyzed using the partial least squares (PLS) approach for the analysis of structural equation models with SmartPLS computer program version 2.0 as research data does not necessarily have a multivariate normal distribution and is less sensitive to sample size than other covariance approaches. PLS results revealed that corporate social responsibility partially mediated the link between consumer awareness of green marketing and purchase intentions of the product in the retail setting. Marketing managers should allocate a sufficient portion of their budget to appropriate corporate social responsibility activities by engaging in voluntary programs for positive return on investment leading to increased business profitability and long run business sustainability. The outcomes of the mediating effects of corporate social responsibility add a new impetus to the growing literature and preceding discoveries on consumer green marketing awareness, which is inadequately researched in the Malaysian setting. Direction for future research is also presented.Keywords: green marketing awareness, social responsibility, partial least squares, purchase intention
Procedia PDF Downloads 6052113 Accurate Cortical Reconstruction in Narrow Sulci with Zero-Non-Zero Distance (ZNZD) Vector Field
Authors: Somojit Saha, Rohit K. Chatterjee, Sarit K. Das, Avijit Kar
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A new force field is designed for propagation of the parametric contour into deep narrow cortical fold in the application of knowledge based reconstruction of cerebral cortex from MR image of brain. Designing of this force field is highly inspired by the Generalized Gradient Vector Flow (GGVF) model and markedly differs in manipulation of image information in order to determine the direction of propagation of the contour. While GGVF uses edge map as its main driving force, the newly designed force field uses the map of distance between zero valued pixels and their nearest non-zero valued pixel as its main driving force. Hence, it is called Zero-Non-Zero Distance (ZNZD) force field. The objective of this force field is forceful propagation of the contour beyond spurious convergence due to partial volume effect (PVE) in to narrow sulcal fold. Being function of the corresponding non-zero pixel value, the force field has got an inherent property to determine spuriousness of the edge automatically. It is effectively applied along with some morphological processing in the application of cortical reconstruction to breach the hindrance of PVE in narrow sulci where conventional GGVF fails.Keywords: deformable model, external force field, partial volume effect, cortical reconstruction, MR image of brain
Procedia PDF Downloads 3982112 The Influence of Audio on Perceived Quality of Segmentation
Authors: Silvio Ricardo Rodrigues Sanches, Bianca Cogo Barbosa, Beatriz Regina Brum, Cléber Gimenez Corrêa
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To evaluate the quality of a segmentation algorithm, the authors use subjective or objective metrics. Although subjective metrics are more accurate than objective ones, objective metrics do not require user feedback to test an algorithm. Objective metrics require subjective experiments only during their development. Subjective experiments typically display to users some videos (generated from frames with segmentation errors) that simulate the environment of an application domain. This user feedback is crucial information for metric definition. In the subjective experiments applied to develop some state-of-the-art metrics used to test segmentation algorithms, the videos displayed during the experiments did not contain audio. Audio is an essential component in applications such as videoconference and augmented reality. If the audio influences the user’s perception, using only videos without audio in subjective experiments can compromise the efficiency of an objective metric generated using data from these experiments. This work aims to identify if the audio influences the user’s perception of segmentation quality in background substitution applications with audio. The proposed approach used a subjective method based on formal video quality assessment methods. The results showed that audio influences the quality of segmentation perceived by a user.Keywords: background substitution, influence of audio, segmentation evaluation, segmentation quality
Procedia PDF Downloads 1182111 Iterative Solver for Solving Large-Scale Frictional Contact Problems
Authors: Thierno Diop, Michel Fortin, Jean Deteix
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Since the precise formulation of the elastic part is irrelevant for the description of the algorithm, we shall consider a generic case. In practice, however, we will have to deal with a non linear material (for instance a Mooney-Rivlin model). We are interested in solving a finite element approximation of the problem, leading to large-scale non linear discrete problems and, after linearization, to large linear systems and ultimately to calculations needing iterative methods. This also implies that penalty method, and therefore augmented Lagrangian method, are to be banned because of their negative effect on the condition number of the underlying discrete systems and thus on the convergence of iterative methods. This is in rupture to the mainstream of methods for contact in which augmented Lagrangian is the principal tool. We shall first present the problem and its discretization; this will lead us to describe a general solution algorithm relying on a preconditioner for saddle-point problems which we shall describe in some detail as it is not entirely standard. We will propose an iterative approach for solving three-dimensional frictional contact problems between elastic bodies, including contact with a rigid body, contact between two or more bodies and also self-contact.Keywords: frictional contact, three-dimensional, large-scale, iterative method
Procedia PDF Downloads 2122110 Adequacy of Second-Generation Laryngeal Mask Airway during Prolonged Abdominal Surgery
Authors: Sukhee Park, Gaab Soo Kim
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Purpose: We aimed to evaluate the adequacy of second-generation laryngeal mask airway use during prolonged abdominal surgery in respect of ventilation, oxygenation, postoperative pulmonary complications (PPC), and postoperative non-pulmonary complications on living donor kidney transplant (LDKT) surgery. Methods: In total, 257 recipients who underwent LDKT using either laryngeal mask airway-ProSeal (LMA-P) or endotracheal tube (ETT) were retrospectively analyzed. Arterial partial pressure of carbon dioxide (PaCO2 and ratio of arterial partial pressure of oxygen to fractional inspired oxygen (PFR) during surgery were compared between two groups. In addition, PPC including pulmonary aspiration and postoperative non-pulmonary complications including nausea, vomiting, hoarseness, vocal cord palsy, delirium, and atrial fibrillation were also compared. Results: PaCO2 and PFR during surgery were not significantly different between the two groups. PPC was also not significantly different between the two groups. Interestingly, the incidence of delirium was significantly lower in the LMA-P group than the ETT group (3.0% vs. 10.3%, P = 0.029). Conclusions: During prolonged abdominal surgery such as LDKT, second-generation laryngeal mask airway offers adequate ventilation and oxygenation and can be considered a suitable alternative to ETT.Keywords: laryngeal mask airway, prolonged abdominal surgery, kidney transplantation, postoperative pulmonary complication
Procedia PDF Downloads 1482109 Effects of Temperature and Cysteine Addition on Formation of Flavor from Maillard Reaction Using Xylose and Rapeseed Meal Peptide
Authors: Zuoyong Zhang, Min Yu, Jinlong Zhao, Shudong He
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The Maillard reaction can produce the flavor enhancing substance through the chemical crosslinking between free amino group of the protein or polypeptide with the carbonyl of the reducing sugar. In this research, solutions of rapeseed meal peptide and D-xylose with or without L-cysteine (RXC or RX) were heated over a range of temperatures (80-140 °C) for 2 h. It was observed that RXs had a severe browning,while RXCs accompanied by more pH decrement with the temperature increasing. Then the correlation among data of quantitative sensory descriptive analysis, free amino acid (FAA) and GC–MS of RXCs and RXs were analyzed using the partial least square regression method. Results suggested that the Maillard reaction product (MRPs) with cysteine formed at 120 °C (RXC-120) had greater sensory properties especially meat-like flavor compared to other MRPs. Meanwhile, it revealed that glutamic and glycine not only had a positive contribution to meaty aroma but also showed a significant and positive influence on umami taste of RXs based on the FAA data. Moreover, the sulfur-containing compounds showed a significant positive correlation with the meat-like flavor of RXCs, while RXs depended on furans and nitrogenous-containing compounds with more caramel-like flavor. Therefore, a MRP with strong meaty flavor could be obtained at 120 °C by addition of cysteine.Keywords: rapeseed meal, Maillard reaction, sensory characteristics, FAA, GC–MS, partial least square regression
Procedia PDF Downloads 2672108 Synchronous Versus Asynchronous Telecollaboration in Intercultural Communication
Authors: Vita Kalnberzina, Lauren Miller Anderson
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The aim of the paper is to report on the results of the telecollaboration project results carried out between the students of the University of Latvia, National Louis University in the US, and Austral University in Chili during the Intercultural Communication course. The objectives of the study are 1) to compare different forms of student telecollaboration and virtual exchange, 2) to collect and analyse the student feedback on the telecollaboration project, 3) to evaluate the products (films) produced during the telecollaboration project. The methods of research used are as follows: Survey of the student feedback after the project, video text analysis of the films produced by the students, and interview of the students participating in the project. We would like to compare the results of a three-year collaboration project, where we tried out synchronous telecollaboration and asynchronous collaboration. The different variables that were observed were the impact of the different time zones, different language proficiency levels of students, and different curricula developed for collaboration. The main findings suggest that the effort spent by students to organize meetings in different time zones and to get to know each other diminishes the quality of the product developed and thus reduces the students' feeling of accomplishment. Therefore, we would like to propose that asynchronous collaboration where the national teams work on a film project specifically developed by the students of one university for the students of another university ends up with a better quality film, which in its turn appeals more to the students of the other university and creates a deeper intercultural bond between the collaborating students.Keywords: telecollaboration, intercultural communication, synchronous collaboration, asynchronous collaboration
Procedia PDF Downloads 1012107 The Role and Effects of Communication on Occupational Safety: A Review
Authors: Pieter A. Cornelissen, Joris J. Van Hoof
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The interest in improving occupational safety started almost simultaneously with the beginning of the Industrial Revolution. Yet, it was not until the late 1970’s before the role of communication was considered in scientific research regarding occupational safety. In recent years the importance of communication as a means to improve occupational safety has increased. Not only as communication might have a direct effect on safety performance and safety outcomes, but also as it can be viewed as a major component of other important safety-related elements (e.g., training, safety meetings, leadership). And while safety communication is an increasingly important topic in research, its operationalization is often vague and differs among studies. This is not only problematic when comparing results, but also in applying these results to practice and the work floor. By means of an in-depth analysis—building on an existing dataset—this review aims to overcome these problems. The initial database search yielded 25.527 articles, which was reduced to a research corpus of 176 articles. Focusing on the 37 articles of this corpus that addressed communication (related to safety outcomes and safety performance), the current study will provide a comprehensive overview of the role and effects of safety communication and outlines the conditions under which communication contributes to a safer work environment. The study shows that in literature a distinction is commonly made between safety communication (i.e., the exchange or dissemination of safety-related information) and feedback (i.e. a reactive form of communication). And although there is a consensus among researchers that both communication and feedback positively affect safety performance, there is a debate about the directness of this relationship. Whereas some researchers assume a direct relationship between safety communication and safety performance, others state that this relationship is mediated by safety climate. One of the key findings is that despite the strongly present view that safety communication is a formal and top-down safety management tool, researchers stress the importance of open communication that encourages and allows employees to express their worries, experiences, views, and share information. This raises questions with regard to other directions (e.g., bottom-up, horizontal) and forms of communication (e.g., informal). The current review proposes a framework to overcome the often vague and different operationalizations of safety communication. The proposed framework can be used to characterize safety communication in terms of stakeholders, direction, and characteristics of communication (e.g., medium usage).Keywords: communication, feedback, occupational safety, review
Procedia PDF Downloads 3032106 Green Materials for Hot Mixed Asphalt Production
Authors: Salisu Dahiru, Jibrin M. Kaura, Abubakar I. Jumare, Sulaiman M. Mahmood
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Reclaimed asphalt, used automobile tires and rice husk, were regarded as waste. These materials could be used in construction of new roads and for roads rehabilitation. Investigation into the production of a Green Hot Mixed Asphalt (GHMA) pavement using Reclaimed Asphalt Pavement (RAP) as partial replacement for coarse aggregate, Crumb Rubber (CR) from waste automobile tires as modifier for bitumen binder and Rice Husk Ash (RHA) as partial replacement of ordinary portland cement (OPC) filler, for roads construction and rehabilitation was presented. 30% Reclaimed asphalt of total aggregate, 15% Crumb Rubber of total binder content, 5% Rice Husk Ash of total mix, and 5.2% Crumb Rubber Modified Bitumen content were recommended for optimum performance. Loss of marshal stability was investigated on mix with the recommended optimum CRMB. The mix revealed good performance with only about 13% loss of stability after 24 hours of immersion in hot water bath, as against about 24% marshal stability lost reported in previous studies for conventional Hot Mixed Asphalt (HMA).Keywords: rice husk, reclaimed asphalt, filler, crumb rubber, bitumen content green hot mix asphalt
Procedia PDF Downloads 3362105 Explicit Numerical Approximations for a Pricing Weather Derivatives Model
Authors: Clarinda V. Nhangumbe, Ercília Sousa
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Weather Derivatives are financial instruments used to cover non-catastrophic weather events and can be expressed in the form of standard or plain vanilla products, structured or exotics products. The underlying asset, in this case, is the weather index, such as temperature, rainfall, humidity, wind, and snowfall. The complexity of the Weather Derivatives structure shows the weakness of the Black Scholes framework. Therefore, under the risk-neutral probability measure, the option price of a weather contract can be given as a unique solution of a two-dimensional partial differential equation (parabolic in one direction and hyperbolic in other directions), with an initial condition and subjected to adequate boundary conditions. To calculate the price of the option, one can use numerical methods such as the Monte Carlo simulations and implicit finite difference schemes conjugated with Semi-Lagrangian methods. This paper is proposed two explicit methods, namely, first-order upwind in the hyperbolic direction combined with Lax-Wendroff in the parabolic direction and first-order upwind in the hyperbolic direction combined with second-order upwind in the parabolic direction. One of the advantages of these methods is the fact that they take into consideration the boundary conditions obtained from the financial interpretation and deal efficiently with the different choices of the convection coefficients.Keywords: incomplete markets, numerical methods, partial differential equations, stochastic process, weather derivatives
Procedia PDF Downloads 852104 A Comprehensive Review of Adaptive Building Energy Management Systems Based on Users’ Feedback
Authors: P. Nafisi Poor, P. Javid
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Over the past few years, the idea of adaptive buildings and specifically, adaptive building energy management systems (ABEMS) has become popular. Well-performed management in terms of energy is to create a balance between energy consumption and user comfort; therefore, in new energy management models, efficient energy consumption is not the sole factor and the user's comfortability is also considered in the calculations. One of the main ways of measuring this factor is by analyzing user feedback on the conditions to understand whether they are satisfied with conditions or not. This paper provides a comprehensive review of recent approaches towards energy management systems based on users' feedbacks and subsequently performs a comparison between them premised upon their efficiency and accuracy to understand which approaches were more accurate and which ones resulted in a more efficient way of minimizing energy consumption while maintaining users' comfortability. It was concluded that the highest accuracy rate among the presented works was 95% accuracy in determining satisfaction and up to 51.08% energy savings can be achieved without disturbing user’s comfort. Considering the growing interest in designing and developing adaptive buildings, these studies can support diverse inquiries about this subject and can be used as a resource to support studies and researches towards efficient energy consumption while maintaining the comfortability of users.Keywords: adaptive buildings, energy efficiency, intelligent buildings, user comfortability
Procedia PDF Downloads 1342103 Design of 900 MHz High Gain SiGe Power Amplifier with Linearity Improved Bias Circuit
Authors: Guiheng Zhang, Wei Zhang, Jun Fu, Yudong Wang
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A 900 MHz three-stage SiGe power amplifier (PA) with high power gain is presented in this paper. Volterra Series is applied to analyze nonlinearity sources of SiGe HBT device model clearly. Meanwhile, the influence of operating current to IMD3 is discussed. Then a β-helper current mirror bias circuit is applied to improve linearity, since the β-helper current mirror bias circuit can offer stable base biasing voltage. Meanwhile, it can also work as predistortion circuit when biasing voltages of three bias circuits are fine-tuned, by this way, the power gain and operating current of PA are optimized for best linearity. The three power stages which fabricated by 0.18 μm SiGe technology are bonded to the printed circuit board (PCB) to obtain impedances by Load-Pull system, then matching networks are done for best linearity with discrete passive components on PCB. The final measured three-stage PA exhibits 21.1 dBm of output power at 1 dB compression point (OP1dB) with power added efficiency (PAE) of 20.6% and 33 dB power gain under 3.3 V power supply voltage.Keywords: high gain power amplifier, linearization bias circuit, SiGe HBT model, Volterra series
Procedia PDF Downloads 341