Search results for: computer mediated power point presentations
Commenced in January 2007
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Paper Count: 13321

Search results for: computer mediated power point presentations

2551 Facial Behavior Modifications Following the Diffusion of the Use of Protective Masks Due to COVID-19

Authors: Andreas Aceranti, Simonetta Vernocchi, Marco Colorato, Daniel Zaccariello

Abstract:

Our study explores the usefulness of implementing facial expression recognition capabilities and using the Facial Action Coding System (FACS) in contexts where the other person is wearing a mask. In the communication process, the subjects use a plurality of distinct and autonomous reporting systems. Among them, the system of mimicking facial movements is worthy of attention. Basic emotion theorists have identified the existence of specific and universal patterns of facial expressions related to seven basic emotions -anger, disgust, contempt, fear, sadness, surprise, and happiness- that would distinguish one emotion from another. However, due to the COVID-19 pandemic, we have come up against the problem of having the lower half of the face covered and, therefore, not investigable due to the masks. Facial-emotional behavior is a good starting point for understanding: (1) the affective state (such as emotions), (2) cognitive activity (perplexity, concentration, boredom), (3) temperament and personality traits (hostility, sociability, shyness), (4) psychopathology (such as diagnostic information relevant to depression, mania, schizophrenia, and less severe disorders), (5) psychopathological processes that occur during social interactions patient and analyst. There are numerous methods to measure facial movements resulting from the action of muscles, see for example, the measurement of visible facial actions using coding systems (non-intrusive systems that require the presence of an observer who encodes and categorizes behaviors) and the measurement of electrical "discharges" of contracting muscles (facial electromyography; EMG). However, the measuring system invented by Ekman and Friesen (2002) - "Facial Action Coding System - FACS" is the most comprehensive, complete, and versatile. Our study, carried out on about 1,500 subjects over three years of work, allowed us to highlight how the movements of the hands and upper part of the face change depending on whether the subject wears a mask or not. We have been able to identify specific alterations to the subjects’ hand movement patterns and their upper face expressions while wearing masks compared to when not wearing them. We believe that finding correlations between how body language changes when our facial expressions are impaired can provide a better understanding of the link between the face and body non-verbal language.

Keywords: facial action coding system, COVID-19, masks, facial analysis

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2550 Educational Experiences in Engineering in the COVID Era and Their Comparative Analysis, Spain, March to June 2020

Authors: Borja Bordel, Ramón Alcarria, Marina Pérez

Abstract:

In March 2020, in Spain, a sanitary and unexpected crisis caused by COVID-19 was declared. All of a sudden, all degrees, classes and evaluation tests and projects had to be transformed into online activities. However, the chaotic situation generated by a complex operation like that, executed without any well-established procedure, led to very different experiences and, finally, results. In this paper, we are describing three experiences in two different Universities in Madrid. On the one hand, the Technical University of Madrid, a public university with little experience in online education. On the other hand, Alfonso X el Sabio University, a private university with more than five years of experience in online teaching. All analyzed subjects were related to computer engineering. Professors and students answered a survey and personal interviews were also carried out. Besides, the professors’ workload and the students’ academic results were also compared. From the comparative analysis of all these experiences, we are extracting the most successful strategies, methodologies, and activities. The recommendations in this paper will be useful for courses during the next months when the sanitary situation is still affecting an educational organization. While, at the same time, they will be considered as input for the upcoming digitalization process of higher education.

Keywords: educational experience, online education, higher education digitalization, COVID, Spain

Procedia PDF Downloads 124
2549 The Image of Saddam Hussein and Collective Memory: The Semiotics of Ba'ath Regime's Mural in Iraq (1980-2003)

Authors: Maryam Pirdehghan

Abstract:

During the Ba'ath Party's rule in Iraq, propaganda was utilized to justify and to promote Saddam Hussein's image in the collective memory as the greatest Arab leader. Consequently, urban walls were routinely covered with images of Saddam. Relying on these images, the regime aimed to provide a basis for evoking meanings in the public opinion, which would supposedly strengthen Saddam’s power and reconstruct facts to legitimize his political ideology. Nonetheless, Saddam was not always portrayed with common and explicit elements but in certain periods of his rule, the paintings depicted him in an unusual context, where various historical and contemporary elements were combined in a narrative background. Therefore, an understanding of the implied socio-political references of these elements is required to fully elucidate the impact of these images on forming the memory and collective unconscious of the Iraqi people. To obtain such understanding, one needs to address the following questions: a) How Saddam Hussein is portrayed in mural during his rule? b) What of elements and mythical-historical narratives are found in the paintings? c) Which Saddam's political views were subject to the collective memory through mural? Employing visual semiotics, this study reveals that during Saddam Hussein's regime, the paintings were initially simple portraits but gradually transformed into narrative images, characterized by a complex network of historical, mythical and religious elements. These elements demonstrate the transformation of a secular-nationalist politician into a Muslim ruler who tried to instill three major policies in domestic and international relations i.e. the arabization of Iraq, as well as the propagation of pan-arabism ideology (first period), the implementation of anti-Israel policy (second period) and the implementation of anti-American-British policy (last period).

Keywords: Ba'ath Party, Saddam Hussein, mural, Iraq, propaganda, collective memory

Procedia PDF Downloads 303
2548 Gender Identify and Agency of Traumatized Subjects in Incestuous Family

Authors: Jenyu Peng

Abstract:

Incestuous abuse can be considered a form of domestic violence that exemplifies gender inequality. It challenges the common image of home as “haven of safety”. In Taiwan, even after years of feminist NGOs’ effort to encourage victims to speak up, the shared cultural representations of family, still praising piety towards the parents, seem to keep the incest trauma in secret. As clinical practitioners have observed, most devastating psychological sequels of incest trauma are often related to silencing. Thus one can expect that in families centered cultures, the difficulties for victims to disclose are greater, and the traumatic consequences more severe. This poses crucial therapeutic issues for clinicians working in those cultures. Since 2009, the author, a trained psychoanalyst and researcher, has been conducting “clinical fieldwork” on incest trauma in Taiwan. Employing ethnographical method, our theoretical references are both psychoanalytical and anthropological. The necessity of interdisciplinary efforts in incest trauma research will be addressed and discussed. The analyses of the present paper will focus on five incestuous families: four Han families, and one aboriginal. Although Taiwanese aboriginal peoples have been pretty much sinicized since decades, it is worth observing the convergent and divergent aspects in these two cultures. Moreover, findings of a previous research conducted in France during 2002-2004 will serve as background for the purpose of comparison. The results will be presented along with three questions: 1) How the perception of family influences the process of disclosure? 2) How the incestuous experience comes into play with victims’ gender identity and sexuality, pivotal for the subjectification? 3) How victims more successful in gendered subjectification modify their dynamics with their traumatizing family? This research finds that most victims tend to defend their own incestuous families, and that victims’ subjectivity and agency are actually entangled in the power structure of incestuous family.

Keywords: incestuous family, subjectification, gender identity, agency

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2547 Loss Function Optimization for CNN-Based Fingerprint Anti-Spoofing

Authors: Yehjune Heo

Abstract:

As biometric systems become widely deployed, the security of identification systems can be easily attacked by various spoof materials. This paper contributes to finding a reliable and practical anti-spoofing method using Convolutional Neural Networks (CNNs) based on the types of loss functions and optimizers. The types of CNNs used in this paper include AlexNet, VGGNet, and ResNet. By using various loss functions including Cross-Entropy, Center Loss, Cosine Proximity, and Hinge Loss, and various loss optimizers which include Adam, SGD, RMSProp, Adadelta, Adagrad, and Nadam, we obtained significant performance changes. We realize that choosing the correct loss function for each model is crucial since different loss functions lead to different errors on the same evaluation. By using a subset of the Livdet 2017 database, we validate our approach to compare the generalization power. It is important to note that we use a subset of LiveDet and the database is the same across all training and testing for each model. This way, we can compare the performance, in terms of generalization, for the unseen data across all different models. The best CNN (AlexNet) with the appropriate loss function and optimizers result in more than 3% of performance gain over the other CNN models with the default loss function and optimizer. In addition to the highest generalization performance, this paper also contains the models with high accuracy associated with parameters and mean average error rates to find the model that consumes the least memory and computation time for training and testing. Although AlexNet has less complexity over other CNN models, it is proven to be very efficient. For practical anti-spoofing systems, the deployed version should use a small amount of memory and should run very fast with high anti-spoofing performance. For our deployed version on smartphones, additional processing steps, such as quantization and pruning algorithms, have been applied in our final model.

Keywords: anti-spoofing, CNN, fingerprint recognition, loss function, optimizer

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2546 Improving Research by the Integration of a Collaborative Dimension in an Information Retrieval (IR) System

Authors: Amel Hannech, Mehdi Adda, Hamid Mcheick

Abstract:

In computer science, the purpose of finding useful information is still one of the most active and important research topics. The most popular application of information retrieval (IR) are Search Engines, they meet users' specific needs and aim to locate the effective information in the web. However, these search engines have some limitations related to the relevancy of the results and the ease to explore those results. In this context, we proposed in previous works a Multi-Space Search Engine model that is based on a multidimensional interpretation universe. In the present paper, we integrate an additional dimension that allows to offer users new research experiences. The added component is based on creating user profiles and calculating the similarity between them that then allow the use of collaborative filtering in retrieving search results. To evaluate the effectiveness of the proposed model, a prototype is developed. The experiments showed that the additional dimension has improved the relevancy of results by predicting the interesting items of users based on their experiences and the experiences of other similar users. The offered personalization service allows users to approve the pertinent items, which allows to enrich their profiles and further improve research.

Keywords: information retrieval, v-facets, user behavior analysis, user profiles, topical ontology, association rules, data personalization

Procedia PDF Downloads 242
2545 Factory Communication System for Customer-Based Production Execution: An Empirical Study on the Manufacturing System Entropy

Authors: Nyashadzashe Chiraga, Anthony Walker, Glen Bright

Abstract:

The manufacturing industry is currently experiencing a paradigm shift into the Fourth Industrial Revolution in which customers are increasingly at the epicentre of production. The high degree of production customization and personalization requires a flexible manufacturing system that will rapidly respond to the dynamic and volatile changes driven by the market. They are a gap in technology that allows for the optimal flow of information and optimal manufacturing operations on the shop floor regardless of the rapid changes in the fixture and part demands. Information is the reduction of uncertainty; it gives meaning and context on the state of each cell. The amount of information needed to describe cellular manufacturing systems is investigated by two measures: the structural entropy and the operational entropy. Structural entropy is the expected amount of information needed to describe scheduled states of a manufacturing system. While operational entropy is the amount of information that describes the scheduled states of a manufacturing system, which occur during the actual manufacturing operation. Using Anylogic simulator a typical manufacturing job shop was set-up with a cellular manufacturing configuration. The cellular make-up of the configuration included; a Material handling cell, 3D Printer cell, Assembly cell, manufacturing cell and Quality control cell. The factory shop provides manufactured parts to a number of clients, and there are substantial variations in the part configurations, new part designs are continually being introduced to the system. Based on the normal expected production schedule, the schedule adherence was calculated from the structural entropy and operation entropy of varying the amounts of information communicated in simulated runs. The structural entropy denotes a system that is in control; the necessary real-time information is readily available to the decision maker at any point in time. For contractive analysis, different out of control scenarios were run, in which changes in the manufacturing environment were not effectively communicated resulting in deviations in the original predetermined schedule. The operational entropy was calculated from the actual operations. From the results obtained in the empirical study, it was seen that increasing, the efficiency of a factory communication system increases the degree of adherence of a job to the expected schedule. The performance of downstream production flow fed from the parallel upstream flow of information on the factory state was increased.

Keywords: information entropy, communication in manufacturing, mass customisation, scheduling

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2544 Influence of the Location of Flood Embankments on the Condition of Oxbow Lakes and Riparian Forests: A Case Study of the Middle Odra River Beds on the Example of Dragonflies (Odonata), Ground Beetles (Coleoptera: Carabidae) and Plant Communities

Authors: Magda Gorczyca, Zofia Nocoń

Abstract:

Past and current studies from different countries showed that river engineering leads to environmental degradation and extinction of many species - often those protected by local and international wildlife conservation laws. Through the years, the main focus of rivers utilization has shifted from industrial applications to recreation and wildlife preservation with a focus on keeping the biodiversity which plays a significant role in preventing climate changes. Thus an opportunity appeared to recreate flooding areas and natural habitats, which are very rare in the scale of Europe. Additionally, river restoration helps to avoid floodings and periodic droughts, which are usually very damaging to the economy. In this research, the biodiversity of dragonflies and ground beetles was analyzed in the context of plant communities and forest stands structure. Results were enriched with data from past and current literature. A comparison was made between two parts of the Odra river. A part where oxbow lake and riparian forest were separated from the river bed by embankment and a part of the river with floodplains left intact. Validity assessment of embankments relocation was made based on the research results. In the period between May and September, insects were collected, phytosociological analysis were taken, and forest stand structure properties were specified. In the part of the river not separated by the embankments, rare and protected species of plants were spotted (e.g., Trapanatans, Salvinianatans) as well as greater species and quantitive diversity of dragonfly. Ground beetles fauna, though, was richer in the area separated by the embankment. Even though the research was done during only one season and in a limited area, the results can be a starting point for further extended research and may contribute to acquiring legal wildlife protection and restoration of the researched area. During the research, the presence of invasive species Impatiens parviflora, Echinocystislobata, and Procyonlotor were observed, which may lead to loss of the natural values of the researched areas.

Keywords: carabidae, floodplains, middle Odra river, Odonata, oxbow lakes, riparian forests

Procedia PDF Downloads 129
2543 Learning Gains and Constraints Resulting from Haptic Sensory Feedback among Preschoolers' Engagement during Science Experimentation

Authors: Marios Papaevripidou, Yvoni Pavlou, Zacharias Zacharia

Abstract:

Embodied cognition and additional (touch) sensory channel theories indicate that physical manipulation is crucial to learning since it provides, among others, touch sensory input, which is needed for constructing knowledge. Given these theories, the use of Physical Manipulatives (PM) becomes a prerequisite for learning. On the other hand, empirical research on Virtual Manipulatives (VM) (e.g., simulations) learning has provided evidence showing that the use of PM, and thus haptic sensory input, is not always a prerequisite for learning. In order to investigate which means of experimentation, PM or VM, are required for enhancing student science learning at the kindergarten level, an empirical study was conducted that sought to investigate the impact of haptic feedback on the conceptual understanding of pre-school students (n=44, age mean=5,7) in three science domains: beam balance (D1), sinking/floating (D2) and springs (D3). The participants were equally divided in two groups according to the type of manipulatives used (PM: presence of haptic feedback, VM: absence of haptic feedback) during a semi-structured interview for each of the domains. All interviews followed the Predict-Observe-Explain (POE) strategy and consisted of three phases: initial evaluation, experimentation, final evaluation. The data collected through the interviews were analyzed qualitatively (open-coding for identifying students’ ideas in each domain) and quantitatively (use of non-parametric tests). Findings revealed that the haptic feedback enabled students to distinguish heavier to lighter objects when held in hands during experimentation. In D1 the haptic feedback did not differentiate PM and VM students' conceptual understanding of the function of the beam as a mean to compare the mass of objects. In D2 the haptic feedback appeared to have a negative impact on PM students’ learning. Feeling the weight of an object strengthen PM students’ misconception that heavier objects always sink, whereas the scientifically correct idea that the material of an object determines its sinking/floating behavior in the water was found to be significantly higher among the VM students than the PM ones. In D3 the PM students outperformed significantly the VM students with regard to the idea that the heavier an object is the more the spring will expand, indicating that the haptic input experienced by the PM students served as an advantage to their learning. These findings point to the fact that PMs, and thus touch sensory input, might not always be a requirement for science learning and that VMs could be considered, under certain circumstances, as a viable means for experimentation.

Keywords: haptic feedback, physical and virtual manipulatives, pre-school science learning, science experimentation

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2542 Bhumastra “Unmanned Ground Vehicle”

Authors: Vivek Krishna, Nikhil Jain, A. Mary Posonia A., Albert Mayan J

Abstract:

Terrorism and insurgency are significant global issues that require constant attention and effort from governments and scientists worldwide. To combat these threats, nations invest billions of dollars in developing new defensive technologies to protect civilians. Breakthroughs in vehicle automation have led to the use of sophisticated machines for many dangerous and critical anti-terrorist activities. Our concept of an "Unmanned Ground Vehicle" can carry out tasks such as border security, surveillance, mine detection, and active combat independently or in tandem with human control. The robot's movement can be wirelessly controlled by a person in a distant location or can travel to a pre-programmed destination autonomously in situations where personal control is not feasible. Our defence system comprises two units: the control unit that regulates mobility and the motion tracking unit. The remote operator robot uses the camera's live visual feed to manually operate both units, and the rover can automatically detect movement. The rover is operated by manpower who controls it using a joystick or mouse, and a wireless modem enables a soldier in a combat zone to control the rover via an additional controller feature.

Keywords: robotics, computer vision, Machine learning, Artificial intelligence, future of AI

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2541 Evaluation of a Data Fusion Algorithm for Detecting and Locating a Radioactive Source through Monte Carlo N-Particle Code Simulation and Experimental Measurement

Authors: Hadi Ardiny, Amir Mohammad Beigzadeh

Abstract:

Through the utilization of a combination of various sensors and data fusion methods, the detection of potential nuclear threats can be significantly enhanced by extracting more information from different data. In this research, an experimental and modeling approach was employed to track a radioactive source by combining a surveillance camera and a radiation detector (NaI). To run this experiment, three mobile robots were utilized, with one of them equipped with a radioactive source. An algorithm was developed in identifying the contaminated robot through correlation between camera images and camera data. The computer vision method extracts the movements of all robots in the XY plane coordinate system, and the detector system records the gamma-ray count. The position of the robots and the corresponding count of the moving source were modeled using the MCNPX simulation code while considering the experimental geometry. The results demonstrated a high level of accuracy in finding and locating the target in both the simulation model and experimental measurement. The modeling techniques prove to be valuable in designing different scenarios and intelligent systems before initiating any experiments.

Keywords: nuclear threats, radiation detector, MCNPX simulation, modeling techniques, intelligent systems

Procedia PDF Downloads 91
2540 A Pedagogical Approach of Children’s Learning by Toys, Perspective: Bangladesh

Authors: Muktadir Ahmed, Sayed Akhlakur Rahaman, Mridha Shihab Mahmud

Abstract:

The parents of Bangladesh have scarcity of knowledge about children play. Most of them do not know which toys are perfect for their children. Appropriate toys for playing is one of the most significant parts of children development from early age, besides for proper amelioration of children’s mental growth and brain capacities, toys play an emergent role. So selection of proper toy for children is very important. A toy forms the sagacity of a child and instructs child’s attitude. In this era of globalization to keep pace with everything children toys are also going forward but in a deleterious way. Maximum toys are now battery-driven and for this psychological developments of children are not increasing in effective way; therefore, pedagogical toys are proper selection. This type of toy inspires the wisdom and helps a child to reveal himself/herself. Pedagogical toys are attractive to children and help to stimulate their imagination. Pedagogical toys help them to build senso-motoric skills and hand-eye coordination. In this study, some children divided into two groups, one group played with pedagogical toys and another group played with conventional toys. This study is going to exhibit the difference between pedagogical and conventional toys for kids. The main aim of this study is to reveal the potency of pedagogical toy for children. To implement this study two Daycare Centers (DCC) Projapoti 1 & 3 of Mymensingh city had chosen. Every DCC having 1.5-6 years old children but for this study 2-5 years old children had been selected. The children of Projapoti-1 played with pedagogical toys and the children of Projapoti-2 played with conventional toys. After 6 weeks of study, the children of Projapoti-1 proved that they have improved their skills more than those children of Projapoti-3 who were playing with conventional toys. The children of Projapoti-1 have developed their touch sensation, muscular movement, imitation power, hand-eye coordination whereas the children of Projapoti-3 have only developed their muscular movement fairly (while running after battery driven toys) which is not better than those children of Projapoti-1. They cannot imitate like the children of Projapoti-1. They just had fun from playing virtual games, battery driven toys, watching cartoons etc. Actually, it is not possible to develop a child’s brain without pedagogical toy.

Keywords: brain development, mental growth, pedagogical toys, play for children

Procedia PDF Downloads 311
2539 Colour Quick Response Code with High Damage Resistance Capability

Authors: Minh Nguyen

Abstract:

Today, QR or Quick Response Codes are prevalent, and mobile/smart devices can efficiently read and understand them. Therefore, we can see their appearance in many areas, such as storing web pages/websites, business phone numbers, redirecting to an app download, business location, social media. The popularity of the QR Code is mainly because of its many advantages, such as it can hold a good amount of information, is small, easy to scan and read by a general RGB camera, and it can still work with some damages on its surface. However, there are still some issues. For instance, some areas needed to be kept untouched for its successful decode (e.g., the “Finder Patterns,” the “Quiet Zone,” etc.), the capability of built-in auto-correction is not robust enough, and it is not flexible enough for many application such as Augment Reality (AR). We proposed a new Colour Quick Response Code that has several advantages over the original ones: (1) there is no untouchable area, (2) it allows up to 40% of the entire code area to be damaged, (3) it is more beneficial for Augmented Reality applications, and (4) it is back-compatible and readable by available QR Code scanners such as Pyzbar. From our experience, our Colour Quick Response Code is significantly more flexible on damage compared to the original QR Code. Our code is believed to be suitable in situations where standard 2D Barcodes fail to work, such as curved and shiny surfaces, for instance, medical blood test sample tubes and syringes.

Keywords: QR code, computer vision, image processing, 2D barcode

Procedia PDF Downloads 100
2538 Combustion Characteristics of Wet Woody Biomass in a Grate Furnace: Including Measurements within the Bed

Authors: Narges Razmjoo, Hamid Sefidari, Michael Strand

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Biomass combustion is a growing technique for heat and power production due to the increasing stringent regulations with CO2 emissions. Grate-fired systems have been regarded as a common and popular combustion technology for burning woody biomass. However, some grate furnaces are not well optimized and may emit significant amount of unwanted compounds such as dust, NOx, CO, and unburned gaseous components. The combustion characteristics inside the fuel bed are of practical interest, as they are directly related to the release of volatiles and affect the stability and the efficiency of the fuel bed combustion. Although numerous studies have been presented on the grate firing of biomass, to the author’s knowledge, none of them have conducted a detailed experimental study within the fuel bed. It is difficult to conduct measurements of temperature and gas species inside the burning bed of the fuel in full-scale boilers. Results from such inside bed measurements can also be applied by the numerical experts for modeling the fuel bed combustion. The current work presents an experimental investigation into the combustion behavior of wet woody biomass (53 %) in a 4 MW reciprocating grate boiler, by focusing on the gas species distribution along the height of the fuel bed. The local concentrations of gases (CO, CO2, CH4, NO, and O2) inside the fuel bed were measured through a glass port situated on the side wall of the furnace. The measurements were carried out at five different heights of the fuel bed, by means of a bent stainless steel probe containing a type-k thermocouple. The sample gas extracted from the fuel bed, through the probe, was filtered and dried and then was analyzed using two infrared spectrometers. Temperatures of about 200-1100 °C were measured close to the grate, indicating that char combustion is occurring at the bottom of the fuel bed and propagates upward. The CO and CO2 concentration varied in the range of 15-35 vol % and 3-16 vol %, respectively, and NO concentration varied between 10-140 ppm. The profile of the gas concentrations distribution along the bed height provided a good overview of the combustion sub-processes in the fuel bed.

Keywords: experimental, fuel bed, grate firing, wood combustion

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2537 Nature of a Supercritical Mesophase

Authors: Hamza Javar Magnier, Leslie V. Woodcock

Abstract:

It has been reported that at temperatures above the critical there is no “continuity of liquid and gas”, as originally hypothesized by van der Waals. Rather, both gas and liquid phases, with characteristic properties as such, extend to supercritical temperatures. Each phase is bounded by the locus of a percolation transition, i.e. a higher-order thermodynamic phase change associated with percolation of gas clusters in a large void, or liquid interstitial vacancies in a large cluster. Between these two-phase bounds, it is reported there exists a mesophase that resembles an otherwise homogeneous dispersion of gas micro-bubbles in liquid (foam) and a dispersion of liquid micro-droplets in gas (mist). Such a colloidal-like state of a pure one-component fluid represents a hitherto unchartered equilibrium state of matter besides pure solid, liquid or gas. Here we provide compelling evidence, from molecular dynamics (MD) simulations, for the existence of this supercritical mesophase and its colloidal nature. We report preliminary results of computer simulations for a model fluid using a simplistic representation of atoms or molecules, i.e. a hard-core repulsion with an attraction so short that the atoms are referred to as “adhesive spheres”. Molecular clusters, and hence percolation transitions, are unambiguously defined. Graphics of color-coded clusters show colloidal characteristics of the supercritical mesophase.

Keywords: critical phenomena, mesophase, supercritical, square-well, critical parameters

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2536 An Analytical Approach for the Fracture Characterization in Concrete under Fatigue Loading

Authors: Bineet Kumar

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Many civil engineering infrastructures frequently encounter repetitive loading during their service life. Due to the inherent complexity observed in concrete, like quasi-brittle materials, understanding the fatigue behavior in concrete still posesa challenge. Moreover, the fracture process zone characteristics ahead of the crack tip have been observed to be different in fatigue loading than in the monotonic cases. Therefore, it is crucial to comprehend the energy dissipation associated with the fracture process zone (FPZ) due to repetitive loading. It is well known that stiffness degradation due to cyclic loadingprovides a better understanding of the fracture behavior of concrete. Under repetitive load cycles, concrete members exhibit a two-stage stiffness degradation process. Experimentally it has been observed that the stiffness decreases initially with an increase in crack length and subsequently increases. In this work, an attempt has been made to propose an analytical expression to predict energy dissipation and later the stiffness degradation as a function of crack length. Three-point bend specimens have been considered in the present work to derive the formulations. In this approach, the expression for the resultant stress distribution below the neutral axis has been derived by correlating the bending stress with the cohesive stresses developed ahead of the crack tip due to the existence of the fracture process zone. This resultant stress expression is utilized to estimate the dissipated energydue to crack propagation as a function of crack length. Further, the formulation for the stiffness degradation has been developed by relating the dissipated energy with the work done. It can be used to predict the critical crack length and fatigue life. An attempt has been made to understand the influence of stress amplitude on the damage pattern by using the information on the rate of stiffness degradation. It has been demonstrated that with the increase in the stress amplitude, the damage/FPZ proceeds more in the direction of crack propagation compared to the damage in the direction parallel to the span of the beam, which causes a lesser rate of stiffness degradation for the incremental crack length. Further, the effect of loading frequency has been investigated in terms of stiffness degradation. Under low-frequency loading cases, the damage/FPZ has been found to spread more in the direction parallel to the span, in turn reducing the critical crack length and fatigue life. In such a case, a higher rate of stiffness degradation has been observed in comparison to the high-frequency loading case.

Keywords: fatigue life, fatigue, fracture, concrete

Procedia PDF Downloads 74
2535 A Comparative Study on Software Patent: The Meaning of 'Use' in Direct Infringement

Authors: Tien Wei Daniel Hwang

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The computer program inventors, particularly in Fintech, are unwilling to apply for patents in Taiwan after 2014. Passing the ‘statutory subject matter eligibility’ test and becoming the system patent are not the only cause to the reduction in the number of application. Taiwanese court needs to resolve whether the defendants had ‘used’ that software patent in patent direct infringement suit. Both 35 U.S.C. § 271(a) and article 58 paragraph 2 of Taiwan Patent Law don’t define the meaning of ‘use’ in the statutes. Centillion Data Sys., LLC v. Qwest Commc’ns Int’l, Inc. reconsidered the meaning of ‘use’ in system patent infringement, and held that ‘a party must put the invention into service, i.e., control the system as a whole and obtain benefit from it.’ In Taiwan, Intellectual Property Office, Ministry of Economic Affairs, has explained that ‘using’ the patent is ‘achieving the technical effect of the patent.’ Nonetheless, this definition is too broad to apply to not only the software patent but also the traditional patent. To supply the friendly environment for Fintech corporations, this article aims to let Taiwanese court realize why and how United States District Court, S.D. Indiana, Indianapolis Division and United States Court of Appeals, Federal Circuit defined the meaning of ‘use’ in 35 U.S.C. § 271(a). However, this definition is so lax and confuses many defendants in United States. Accordingly, this article indicates the elements in Taiwan Patent Law are different with 35 U.S.C. § 271(a), so Taiwanese court can follow the interpretation of ‘use’ in Centillion Data case without the same obstacle.

Keywords: direct infringement, FinTech, software patent, use

Procedia PDF Downloads 287
2534 Ability of Gastric Enzyme Extract of Adult Camel to Clot Bovine Milk

Authors: Boudjenah-Haroun Saliha, Isselnane Souad, Nouani Abdelwahab, Baaissa Babelhadj, Mati Abderrahmane

Abstract:

Algeria is experiencing significant development of the dairy sector, where consumption of milk and milk products increased by 2.7 million tons in 2008 to 4,400,000 tons in 2013, and cheese production has reached 1640 tons in the year 2014 with average consumption of 0.7 kg/person/year. Although rennet is still the most used coagulating enzyme in cheese, its production has been growing worldwide shortage. This shortage is primarily due to a growing increase in the production and consumption of cheese, and the inability to increase in parallel the production of rennet. This shortage has caused very large fluctuations in its price). To overcome these obstacles, much research has been undertaken to find effective and competitive substitutes used industrially. For this, the selection of a local production of rennet substitute is desirable. It would allow a permanent supply with limited dependence on imports and price fluctuations. Investigations conducted by our research team showed that extracts coagulants from the stomachs of older camels are characterized by a coagulating power than those from younger camels. The objective of this work is to study the possibility of substituting commercial rennet coagulant by gastric enzymes from adult camels for coagulation bovine milk. Excerpts from the raw camel coagulants obtained are characterized through their teneures proteins and clotting and proteolytic activities. Milk clotting conditions by the action of these extracts were optimized. Milk clotting time all treated with enzyme preparations and under different conditions was calculated. Bovine rennet has been used for comparison. The results show that crude extracts from gastric adult camel can be good substituting bovine rennet.

Keywords: Algeria, camel, cheese, coagulation, gastric extracts, milk

Procedia PDF Downloads 420
2533 Predicting Aggregation Propensity from Low-Temperature Conformational Fluctuations

Authors: Hamza Javar Magnier, Robin Curtis

Abstract:

There have been rapid advances in the upstream processing of protein therapeutics, which has shifted the bottleneck to downstream purification and formulation. Finding liquid formulations with shelf lives of up to two years is increasingly difficult for some of the newer therapeutics, which have been engineered for activity, but their formulations are often viscous, can phase separate, and have a high propensity for irreversible aggregation1. We explore means to develop improved predictive ability from a better understanding of how protein-protein interactions on formulation conditions (pH, ionic strength, buffer type, presence of excipients) and how these impact upon the initial steps in protein self-association and aggregation. In this work, we study the initial steps in the aggregation pathways using a minimal protein model based on square-well potentials and discontinuous molecular dynamics. The effect of model parameters, including range of interaction, stiffness, chain length, and chain sequence, implies that protein models fold according to various pathways. By reducing the range of interactions, the folding- and collapse- transition come together, and follow a single-step folding pathway from the denatured to the native state2. After parameterizing the model interaction-parameters, we developed an understanding of low-temperature conformational properties and fluctuations, and the correlation to the folding transition of proteins in isolation. The model fluctuations increase with temperature. We observe a low-temperature point, below which large fluctuations are frozen out. This implies that fluctuations at low-temperature can be correlated to the folding transition at the melting temperature. Because proteins “breath” at low temperatures, defining a native-state as a single structure with conserved contacts and a fixed three-dimensional structure is misleading. Rather, we introduce a new definition of a native-state ensemble based on our understanding of the core conservation, which takes into account the native fluctuations at low temperatures. This approach permits the study of a large range of length and time scales needed to link the molecular interactions to the macroscopically observed behaviour. In addition, these models studied are parameterized by fitting to experimentally observed protein-protein interactions characterized in terms of osmotic second virial coefficients.

Keywords: protein folding, native-ensemble, conformational fluctuation, aggregation

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2532 Contribution Of Community-based House To House (H2h) Active Tuberculosis (Tb) Case Finding (Acf) To Increase In Tb Notification In Nigeria: Kano State Experience 2012 To 2022

Authors: Ibrahim Umar, S Chindo, A Rajab

Abstract:

Background: TB remains a disease of public health concern in Nigeria with an estimated incidence rate of 219/100,000. Kano has the second highest TB burden in Nigeria and is the leading state with the highest consistent yearly TB notification. House-to-house (H2H) active case search in the community was found to have major contribution to the total TB notification in the state. Aims and Objective: To showcase the impact of H2H community active TB case search (ACF) to yearly TB notification in Kano State, Northern Nigeria from 2012 to 2022. Methodology: This is a retrospective descriptive study based on the analysis of data collected during the routine quarterly and yearly TB data collected in the state. Data was analyzed using the Power BI with statistical alpha level of significance <0.05. Results: Between 2012 and 2013 there was no House-to-house active TB case search in Nigeria and Kano had zero contribution to TB notification from the community in those years. However, in 2014 with the introduction of H2H Active TB Case Search Kano notified 6,014 TB cases out of which 113 came from the community ACF that translated to 2% contribution to total TB notification. From 2014 to 2022 there was progressive increase in community contribution to TB case notification from 113 out of 6,014 total TB patients notified (2012) to 11,799 out of 26,371 TB patients notified (2022) in Kano State. This translated to 45% increase in community contribution to total TB case notification. Discussion: Remarkable increase in community contribution to total TB case notification in Kano State was achieved in 2022 with 11,799 TB cases notified from the community Active TB case search to the total of 26,731 TB cases notified in Kano State, Nigeria. Conclusion: in research has shown that Community-based H2H Active TB Case Search through Community TB Workers (CTWs) is an excellent strategy in finding the missing TB cases towards Ending TB in the world.

Keywords: tuberculosis(TB), active case search (ACF), house-to-house (H2H), community TB workers (CTWs)

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2531 Harmonization of Accreditation Standards in Education of Central Asian Countries: Theoretical Aspect

Authors: Yskak Nabi, Onolkan Umankulova, Ilyas Seitov

Abstract:

Tempus project about “Central Asian network for quality assurance – CANQA” had been implemented in 2009-2012. As the result of the project, two accreditation agencies were established: the agency for quality assurance in the field of education, “EdNet” in Kyrgyzstan, center of progressive technologies in Tajikistan. The importance of the research studies of the project is supported by the idea that the creation of Central-Asian network for quality assurance in education is still relevant, and results of the International forum “Global in regional: Kazakhstan in Bologna process and EU projects,” that was held in Nur-Sultan in October 2020, proves this. At the same time, the previous experience of the partnership between accreditation agencies of Central Asia shows that recommendations elaborated within the CANQA project were not theoretically justified. But there are a number of facts and arguments that prove the practical appliance of these recommendations. In this respect, joint activities of accreditation agencies of Kyrgyzstan and Kazakhstan are representative. For example, independent Kazakh agency of accreditation and rating successfully conducts accreditation of Kyrgyz universities; based on the memorandum about joint activity between the agency for quality assurance in the field of education “EdNet” (Kyrgyzstan) and Astana accreditation agency (Kazakhstan), the last one provides its experts for accreditation procedures in EdNet. Exchange of experience among the agencies shows an effective approach towards adaptation of European standards to the reality of education systems of Central Asia with consideration of not only a legal framework but also from the point of European practices view. Therefore, the relevance of the research is identified as there is a practical partnership between accreditation agencies of Central Asian countries, but the absence of theoretical justification of integrational processes in the accreditation field. As a result, the following hypothesis was put forward: “if to develop theoretical aspects for harmonization of accreditation standards, then integrational processes would be improved since the implementation of Bologna process principles would be supported with wider possibilities, and particularly, students and academic mobility would be improved.” Indeed, for example, in Kazakhstan, the total share of foreign students was 5,04% in 2020, and most of them are coming from Kyrgyzstan, Tajikistan, and Uzbekistan, and if integrational processes will be improved, then this share can increase.

Keywords: accreditation standards in education, Central Asian countries, pedagogical theory, model

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2530 Impact of Social Crisis on Property Market Performance and Evolving Strategy for Improved Property Transactions in Crisis Prone Environment: A Case Study of North Eastern Nigeria

Authors: A. Yakub AbdurRaheem

Abstract:

Urban violence in the form of ethnic and religious conflicts have been on the increase in many African cities in the recent years of which most of them are the result of intense and bitter competition for political power, the control of limited economic, social and environmental resources. In Nigeria, the emergence of the Boko Haram insurgency in most parts of the northeastern parts have ignited violence, bloodshed, refugee exodus and internal migration. Not only do the persistent attacks of the sect create widespread insecurity and fear, but it has also stifled normal processes of trade and investments most especially real property investment which is acclaimed to accelerate the economic cycle, thus the need to evolve strategies for an improved property market in such areas. This paper, therefore, examines the impact of this social crisis on effective and efficient utilization of real properties as a resource towards the development of the economy, using a descriptive analysis approach where particular emphasis was based on trends in residential housing values; volume of estimated property transactions and real estate investment decisions by affected individuals. Findings indicate that social crisis in the affected areas have been a clog on the wheels of property development and investment as properties worth hundreds of millions have been destroyed thereby having great impact on property values. Based on these findings, recommendations were made to include the need to strategically continue investing in property during such times, the need for Nigerian government to establish an active conflict monitoring and management unit for the prompt response, encourage community and neighborhood policing to ameliorate security challenges in Nigeria.

Keywords: social crisis, economy, resources, property market

Procedia PDF Downloads 224
2529 Climate Change Impact on Water Resources Management in Remote Islands Using Hybrid Renewable Energy Systems

Authors: Elissavet Feloni, Ioannis Kourtis, Konstantinos Kotsifakis, Evangelos Baltas

Abstract:

Water inadequacy in small dry islands scattered in the Aegean Sea (Greece) is a major problem regarding Water Resources Management (WRM), especially during the summer period due to tourism. In the present work, various WRM schemes are designed and presented. The WRM schemes take into account current infrastructure and include Rainwater Harvesting tanks and Reverse Osmosis Desalination Units. The energy requirements are covered mainly by wind turbines and/or a seawater pumped storage system. Sizing is based on the available data for population and tourism per island, after taking into account a slight increase in the population (up to 1.5% per year), and it guarantees at least 80% reliability for the energy supply and 99.9% for potable water. Evaluation of scenarios is carried out from a financial perspective, after calculating the Life Cycle Cost (LCC) of each investment for a lifespan of 30 years. The wind-powered desalination plant was found to be the most cost-effective practice, from an economic point of view. Finally, in order to estimate the Climate Change (CC) impact, six different CC scenarios were investigated. The corresponding rate of on-grid versus off-grid energy required for ensuring the targeted reliability for the zero and each climatic scenario was investigated per island. The results revealed that under CC the grid-on energy required would increase and as a result, the reduction in wind turbines and seawater pumped storage systems’ reliability will be in the range of 4 to 44%. However, the range of this percentage change does not exceed 22% per island for all examined CC scenarios. Overall, CC is proposed to be incorporated into the design process for WRM-related projects. Acknowledgements: This research is co-financed by Greece and the European Union (European Social Fund - ESF) through the Operational Program «Human Resources Development, Education and Lifelong Learning 2014-2020» in the context of the project “Development of a combined rain harvesting and renewable energy-based system for covering domestic and agricultural water requirements in small dry Greek Islands” (MIS 5004775).

Keywords: small dry islands, water resources management, climate change, desalination, RES, seawater pumped storage system, rainwater harvesting

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2528 Effect of Downstream Pressure in Tuning the Flow Control Orifices of Pressure Fed Reaction Control System Thrusters

Authors: Prakash M.N, Mahesh G, Muhammed Rafi K.M, Shiju P. Nair

Abstract:

Introduction: In launch vehicle missions, Reaction Control thrusters are being used for the three-axis stabilization of the vehicle during the coasting phases. A pressure-fed propulsion system is used for the operation of these thrusters due to its less complexity. In liquid stages, these thrusters are designed to draw propellant from the same tank used for the main propulsion system. So in order to regulate the propellant flow rates of these thrusters, flow control orifices are used in feed lines. These orifices are calibrated separately as per the flow rate requirement of individual thrusters for the nominal operating conditions. In some missions, it was observed that the thrusters were operated at higher thrust than nominal. This point was addressed through a series of cold flow and hot tests carried out in-ground and this paper elaborates the details of the same. Discussion: In order to find out the exact reason for this phenomenon, two flight configuration thrusters were identified and hot tested in the ground with calibrated orifices and feed lines. During these tests, the chamber pressure, which is directly proportional to the thrust, is measured. In both cases, chamber pressures higher than the nominal by 0.32bar to 0.7bar were recorded. The increase in chamber pressure is due to an increase in the oxidizer flow rate of both the thrusters. Upon further investigation, it is observed that the calibration of the feed line is done with ambient pressure downstream. But in actual flight conditions, the orifices will be subjected to operate with 10 to 11bar pressure downstream. Due to this higher downstream pressure, the flow through the orifices increases and thereby, the thrusters operate with higher chamber pressure values. Conclusion: As part of further investigatory tests, two numbers of fresh thrusters were realized. Orifice tuning of these thrusters was carried out in three different ways. In the first trial, the orifice tuning was done by simulating 1bar pressure downstream. The second trial was done with the injector assembled downstream. In the third trial, the downstream pressure equal to the flight injection pressure was simulated downstream. Using these calibrated orifices, hot tests were carried out in simulated vacuum conditions. Chamber pressure and flow rate values were exactly matching with the prediction for the second and third trials. But for the first trial, the chamber pressure values obtained in the hot test were more than the prediction. This clearly shows that the flow is detached in the 1st trial and attached for the 2nd & 3rd trials. Hence, the error in tuning the flow control orifices is pinpointed as the reason for this higher chamber pressure observed in flight.

Keywords: reaction control thruster, propellent, orifice, chamber pressure

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2527 Correlation Analysis to Quantify Learning Outcomes for Different Teaching Pedagogies

Authors: Kanika Sood, Sijie Shang

Abstract:

A fundamental goal of education includes preparing students to become a part of the global workforce by making beneficial contributions to society. In this paper, we analyze student performance for multiple courses that involve different teaching pedagogies: a cooperative learning technique and an inquiry-based learning strategy. Student performance includes student engagement, grades, and attendance records. We perform this study in the Computer Science department for online and in-person courses for 450 students. We will perform correlation analysis to study the relationship between student scores and other parameters such as gender, mode of learning. We use natural language processing and machine learning to analyze student feedback data and performance data. We assess the learning outcomes of two teaching pedagogies for undergraduate and graduate courses to showcase the impact of pedagogical adoption and learning outcome as determinants of academic achievement. Early findings suggest that when using the specified pedagogies, students become experts on their topics and illustrate enhanced engagement with peers.

Keywords: bag-of-words, cooperative learning, education, inquiry-based learning, in-person learning, natural language processing, online learning, sentiment analysis, teaching pedagogy

Procedia PDF Downloads 64
2526 Modeling and Design of E-mode GaN High Electron Mobility Transistors

Authors: Samson Mil'shtein, Dhawal Asthana, Benjamin Sullivan

Abstract:

The wide energy gap of GaN is the major parameter justifying the design and fabrication of high-power electronic components made of this material. However, the existence of a piezo-electrics in nature sheet charge at the AlGaN/GaN interface complicates the control of carrier injection into the intrinsic channel of GaN HEMTs (High Electron Mobility Transistors). As a result, most of the transistors created as R&D prototypes and all of the designs used for mass production are D-mode devices which introduce challenges in the design of integrated circuits. This research presents the design and modeling of an E-mode GaN HEMT with a very low turn-on voltage. The proposed device includes two critical elements allowing the transistor to achieve zero conductance across the channel when Vg = 0V. This is accomplished through the inclusion of an extremely thin, 2.5nm intrinsic Ga₀.₇₄Al₀.₂₆N spacer layer. The added spacer layer does not create piezoelectric strain but rather elastically follows the variations of the crystal structure of the adjacent GaN channel. The second important factor is the design of a gate metal with a high work function. The use of a metal gate with a work function (Ni in this research) greater than 5.3eV positioned on top of n-type doped (Nd=10¹⁷cm⁻³) Ga₀.₇₄Al₀.₂₆N creates the necessary built-in potential, which controls the injection of electrons into the intrinsic channel as the gate voltage is increased. The 5µm long transistor with a 0.18µm long gate and a channel width of 30µm operate at Vd=10V. At Vg =1V, the device reaches the maximum drain current of 0.6mA, which indicates a high current density. The presented device is operational at frequencies greater than 10GHz and exhibits a stable transconductance over the full range of operational gate voltages.

Keywords: compound semiconductors, device modeling, enhancement mode HEMT, gallium nitride

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2525 A Web Application for Screening Dyslexia in Greek Students

Authors: Antonios Panagopoulos, Stamoulis Georgios

Abstract:

Dyslexia's diagnosis is made taking into account reading and writing skills and is carried out by qualified scientific staff. In addition, there are screening tests that are designed to give an indication of possible dyslexic difficulties. Their main advantage is that they create a pleasant environment for the user and reduce the stress that can lead to false results. An online application was created for the first time, as far as authors' knowledge, for screening Dyslexia in Greek high school students named «DyScreTe». Thus, a sample of 240 students between 16 and 18 years old in Greece was taken, of which 120 were diagnosed with dyslexia by an official authority in Greece, and 120 were typically developed. The main hypothesis that was examined is that students who were diagnosed with dyslexia by official authorities in Greece had significantly lower performance in the respective software tests. The results verified the hypothesis we made those children with dyslexia in each test had a lower performance com-pared to the type developed in successful responses, except for the intelligence test. After random sampling, it was shown that the new online application was a useful tool for screening dyslexia. However, computer evaluation cannot replace the diagnosis by a professional expert, but with the results of this application, the interdisciplinary team that deals with the differential diagnosis will create and evaluate, at a later time, the appropriate intervention program.

Keywords: dyslexia, screening tests, deficits, application

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2524 Factors Affecting Sustainability of a 3D Printed Object

Authors: Kadrefi Athanasia, Fronimaki Evgenia, Mavri Maria

Abstract:

3D Printing (3DP) is a distinct, disruptive technology that belongs to a wider group of manufacturing technologies, Additive Manufacturing (AM). In 3DP, a custom digital file turns into a solid object using a single computer and a 3D printer. Among multiple advantages, 3DP offers production with fewer steps compared to conventional manufacturing, lower production costs, and customizable designs. 3DP can be performed by several techniques, while the most common is Fused Deposition Modeling (FDM). FDM belongs to a wider group of AM techniques, material extrusion, where a digital file converts into a solid object using raw material (called filament) melted in high temperatures. As in most manufacturing procedures, environmental issues have been raised here, too. This study aims to review the literature on issues that determine technical and mechanical factors that affect the sustainability and resilience of a final 3D-printed object. The research focuses on the collection of papers that deal with 3D printing techniques and use keywords or phrases like ‘3D printed objects’, ‘factors of 3DP sustainability’, ‘waste materials,’ ‘infill patterns,’ and ‘support structures.’ After determining factors, a pilot survey will be conducted at the 3D Printing Lab in order to define the significance of each factor in the final 3D printed object.

Keywords: additive manufacturing, 3D printing, sustainable manufacturing, sustainable production

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2523 Perceptions of College Students on Whether an Intelligent Tutoring System Is a Tutor

Authors: Michael Smalenberger

Abstract:

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

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2522 Real-Time Classification of Hemodynamic Response by Functional Near-Infrared Spectroscopy Using an Adaptive Estimation of General Linear Model Coefficients

Authors: Sahar Jahani, Meryem Ayse Yucel, David Boas, Seyed Kamaledin Setarehdan

Abstract:

Near-infrared spectroscopy allows monitoring of oxy- and deoxy-hemoglobin concentration changes associated with hemodynamic response function (HRF). HRF is usually affected by natural physiological hemodynamic (systemic interferences) which occur in all body tissues including brain tissue. This makes HRF extraction a very challenging task. In this study, we used Kalman filter based on a general linear model (GLM) of brain activity to define the proportion of systemic interference in the brain hemodynamic. The performance of the proposed algorithm is evaluated in terms of the peak to peak error (Ep), mean square error (MSE), and Pearson’s correlation coefficient (R2) criteria between the estimated and the simulated hemodynamic responses. This technique also has the ability of real time estimation of single trial functional activations as it was applied to classify finger tapping versus resting state. The average real-time classification accuracy of 74% over 11 subjects demonstrates the feasibility of developing an effective functional near infrared spectroscopy for brain computer interface purposes (fNIRS-BCI).

Keywords: hemodynamic response function, functional near-infrared spectroscopy, adaptive filter, Kalman filter

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