Search results for: factor models
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 11311

Search results for: factor models

991 Modeling Floodplain Vegetation Response to Groundwater Variability Using ArcSWAT Hydrological Model, Moderate Resolution Imaging Spectroradiometer - Normalised Difference Vegetation Index Data, and Machine Learning

Authors: Newton Muhury, Armando A. Apan, Tek Maraseni

Abstract:

This study modelled the relationships between vegetation response and available water below the soil surface using the Terra’s Moderate Resolution Imaging Spectroradiometer (MODIS) generated Normalised Difference Vegetation Index (NDVI) and soil water content (SWC) data. The Soil & Water Assessment Tool (SWAT) interface known as ArcSWAT was used in ArcGIS for the groundwater analysis. The SWAT model was calibrated and validated in SWAT-CUP software using 10 years (2001-2010) of monthly streamflow data. The average Nash-Sutcliffe Efficiency during the calibration and validation was 0.54 and 0.51, respectively, indicating that the model performances were good. Twenty years (2001-2020) of monthly MODIS NDVI data for three different types of vegetation (forest, shrub, and grass) and soil water content for 43 sub-basins were analysed using the WEKA, machine learning tool with a selection of two supervised machine learning algorithms, i.e., support vector machine (SVM) and random forest (RF). The modelling results show that different types of vegetation response and soil water content vary in the dry and wet season. For example, the model generated high positive relationships (r=0.76, 0.73, and 0.81) between the measured and predicted NDVI values of all vegetation in the study area against the groundwater flow (GW), soil water content (SWC), and the combination of these two variables, respectively, during the dry season. However, these relationships were reduced by 36.8% (r=0.48) and 13.6% (r=0.63) against GW and SWC, respectively, in the wet season. On the other hand, the model predicted a moderate positive relationship (r=0.63) between shrub vegetation type and soil water content during the dry season, which was reduced by 31.7% (r=0.43) during the wet season. Our models also predicted that vegetation in the top location (upper part) of the sub-basin is highly responsive to GW and SWC (r=0.78, and 0.70) during the dry season. The results of this study indicate the study region is suitable for seasonal crop production in dry season. Moreover, the results predicted that the growth of vegetation in the top-point location is highly dependent on groundwater flow in both dry and wet seasons, and any instability or long-term drought can negatively affect these floodplain vegetation communities. This study has enriched our knowledge of vegetation responses to groundwater in each season, which will facilitate better floodplain vegetation management.

Keywords: ArcSWAT, machine learning, floodplain vegetation, MODIS NDVI, groundwater

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990 Towards End-To-End Disease Prediction from Raw Metagenomic Data

Authors: Maxence Queyrel, Edi Prifti, Alexandre Templier, Jean-Daniel Zucker

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Analysis of the human microbiome using metagenomic sequencing data has demonstrated high ability in discriminating various human diseases. Raw metagenomic sequencing data require multiple complex and computationally heavy bioinformatics steps prior to data analysis. Such data contain millions of short sequences read from the fragmented DNA sequences and stored as fastq files. Conventional processing pipelines consist in multiple steps including quality control, filtering, alignment of sequences against genomic catalogs (genes, species, taxonomic levels, functional pathways, etc.). These pipelines are complex to use, time consuming and rely on a large number of parameters that often provide variability and impact the estimation of the microbiome elements. Training Deep Neural Networks directly from raw sequencing data is a promising approach to bypass some of the challenges associated with mainstream bioinformatics pipelines. Most of these methods use the concept of word and sentence embeddings that create a meaningful and numerical representation of DNA sequences, while extracting features and reducing the dimensionality of the data. In this paper we present an end-to-end approach that classifies patients into disease groups directly from raw metagenomic reads: metagenome2vec. This approach is composed of four steps (i) generating a vocabulary of k-mers and learning their numerical embeddings; (ii) learning DNA sequence (read) embeddings; (iii) identifying the genome from which the sequence is most likely to come and (iv) training a multiple instance learning classifier which predicts the phenotype based on the vector representation of the raw data. An attention mechanism is applied in the network so that the model can be interpreted, assigning a weight to the influence of the prediction for each genome. Using two public real-life data-sets as well a simulated one, we demonstrated that this original approach reaches high performance, comparable with the state-of-the-art methods applied directly on processed data though mainstream bioinformatics workflows. These results are encouraging for this proof of concept work. We believe that with further dedication, the DNN models have the potential to surpass mainstream bioinformatics workflows in disease classification tasks.

Keywords: deep learning, disease prediction, end-to-end machine learning, metagenomics, multiple instance learning, precision medicine

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989 Multimodal Ophthalmologic Evaluation Can Detect Retinal Injuries in Asymptomatic Patients With Primary Antiphospholipid Syndrome

Authors: Taurino S. R. Neto, Epitácio D. S. Neto, Flávio Signorelli, Gustavo G. M. Balbi, Alex H. Higashi, Mário Luiz R. Monteiro, Eloisa Bonfá, Danieli C. O. Andrade, Leandro C. Zacharias

Abstract:

Purpose: To perform a multimodal evaluation, including the use of Optical Coherence Angiotomography (OCTA), in patients with primary antiphospholipid syndrome (PAPS) without ocular complaints and to compare them with healthy individuals. Methods: A complete structural and functional ophthalmological evaluation using OCTA and microperimetry (MP) exam in patients with PAPS, followed at a tertiary rheumatology outpatient clinic, was performed. All ophthalmologic manifestations were recorded and then statistical analysis was performed for comparative purposes; p <0.05 was considered statistically significant. Results: 104 eyes of 52 subjects (26 patients with PAPS without ocular complaints and 26 healthy individuals) were included. Among PAPS patients, 21 were female (80.8%) and 21 (80.8%) were Caucasians. Thrombotic PAPS was the main clinical criteria manifestation (100%); 65.4% had venous and 34.6% had arterial thrombosis. Obstetrical criteria were present in 34.6% of all thrombotic PAPS patients. Lupus anticoagulant was present in all patients. 19.2% of PAPS patients presented ophthalmologic findings against none of the healthy individuals. The most common retinal change was paracentral acute middle maculopathy (PAMM) (3 patients, 5 eyes), followed by drusen-like deposits (1 patient, 2 eyes) and pachychoroid pigment epitheliopathy (1 patient, 1 eye). Systemic hypertension and hyperlipidaemia were present in 100% of the PAPS patients with PAMM, while only six patients (26.1%) with PAPS without PAMM presented these two risk factors together. In the quantitative OCTA evaluation, we found significant differences between PAPS patients and controls in both the superficial vascular complex (SVC) and deep vascular complex (DVC) in the high-speed protocol, as well as in the SVC in the high-resolution protocol. In the analysis of the foveal avascular zone (FAZ) parameters, the PAPS group had a larger area of FAZ in the DVC using the high-speed method compared to the control group (p=0.047). In the quantitative analysis of the MP, the PAPS group had lower central (p=0.041) and global (p<0.001) retinal sensitivity compared to the control group, as well as in the sector analysis, with the exception of the inferior sector. In the quantitative evaluation of fixation stability, there was a trend towards worse stability in the PAPS subgroup with PAMM in both studied methods. Conclusions: PAMM was observed in 11.5% of PAPS patients with no previous ocular complaints. Systemic hypertension concomitant with hyperlipidemia was the most commonly associated risk factor for PAMM in patients with PAPS. PAPS patients present lower vascular density and retinal sensitivity compared to the control group, even in patients without PAMM.

Keywords: antiphospholipid syndrome, optical coherence angio tomography, optical coherence tomography, retina

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988 Character Development Outcomes: A Predictive Model for Behaviour Analysis in Tertiary Institutions

Authors: Rhoda N. Kayongo

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As behavior analysts in education continue to debate on how higher institutions can continue to benefit from their social and academic related programs, higher education is facing challenges in the area of character development. This is manifested in the percentages of college completion rates, teen pregnancies, drug abuse, sexual abuse, suicide, plagiarism, lack of academic integrity, and violence among their students. Attending college is a perceived opportunity to positively influence the actions and behaviors of the next generation of society; thus colleges and universities have to provide opportunities to develop students’ values and behaviors. Prior studies were mainly conducted in private institutions and more so in developed countries. However, with the complexity of the nature of student body currently due to the changing world, a multidimensional approach combining multiple factors that enhance character development outcomes is needed to suit the changing trends. The main purpose of this study was to identify opportunities in colleges and develop a model for predicting character development outcomes. A survey questionnaire composed of 7 scales including in-classroom interaction, out-of-classroom interaction, school climate, personal lifestyle, home environment, and peer influence as independent variables and character development outcomes as the dependent variable was administered to a total of five hundred and one students of 3rd and 4th year level in selected public colleges and universities in the Philippines and Rwanda. Using structural equation modelling, a predictive model explained 57% of the variance in character development outcomes. Findings from the results of the analysis showed that in-classroom interactions have a substantial direct influence on character development outcomes of the students (r = .75, p < .05). In addition, out-of-classroom interaction, school climate, and home environment contributed to students’ character development outcomes but in an indirect way. The study concluded that in the classroom are many opportunities for teachers to teach, model and integrate character development among their students. Thus, suggestions are made to public colleges and universities to deliberately boost and implement experiences that cultivate character within the classroom. These may contribute tremendously to the students' character development outcomes and hence render effective models of behaviour analysis in higher education.

Keywords: character development, tertiary institutions, predictive model, behavior analysis

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987 Optimization of Dez Dam Reservoir Operation Using Genetic Algorithm

Authors: Alireza Nikbakht Shahbazi, Emadeddin Shirali

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Since optimization issues of water resources are complicated due to the variety of decision making criteria and objective functions, it is sometimes impossible to resolve them through regular optimization methods or, it is time or money consuming. Therefore, the use of modern tools and methods is inevitable in resolving such problems. An accurate and essential utilization policy has to be determined in order to use natural resources such as water reservoirs optimally. Water reservoir programming studies aim to determine the final cultivated land area based on predefined agricultural models and water requirements. Dam utilization rule curve is also provided in such studies. The basic information applied in water reservoir programming studies generally include meteorological, hydrological, agricultural and water reservoir related data, and the geometric characteristics of the reservoir. The system of Dez dam water resources was simulated applying the basic information in order to determine the capability of its reservoir to provide the objectives of the performed plan. As a meta-exploratory method, genetic algorithm was applied in order to provide utilization rule curves (intersecting the reservoir volume). MATLAB software was used in order to resolve the foresaid model. Rule curves were firstly obtained through genetic algorithm. Then the significance of using rule curves and the decrease in decision making variables in the system was determined through system simulation and comparing the results with optimization results (Standard Operating Procedure). One of the most essential issues in optimization of a complicated water resource system is the increasing number of variables. Therefore a lot of time is required to find an optimum answer and in some cases, no desirable result is obtained. In this research, intersecting the reservoir volume has been applied as a modern model in order to reduce the number of variables. Water reservoir programming studies has been performed based on basic information, general hypotheses and standards and applying monthly simulation technique for a statistical period of 30 years. Results indicated that application of rule curve prevents the extreme shortages and decrease the monthly shortages.

Keywords: optimization, rule curve, genetic algorithm method, Dez dam reservoir

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986 Evaluation of Air Movement, Humidity and Temperature Perceptions with the Occupant Satisfaction in Office Buildings in Hot and Humid Climate Regions by Means of Field Surveys

Authors: Diego S. Caetano, Doreen E. Kalz, Louise L. B. Lomardo, Luiz P. Rosa

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The energy consumption in non-residential buildings in Brazil has a great impact on the national infrastructure. The growth of the energy consumption has a special role over the building cooling systems, supported by the increased people's requirements on hygrothermal comfort. This paper presents how the occupants of office buildings notice and evaluate the hygrothermic comfort regarding temperature, humidity, and air movement, considering the cooling systems presented at the buildings studied, analyzed by real occupants in areas of hot and humid climate. The paper presents results collected over a long time from 3 office buildings in the cities of Rio de Janeiro and Niteroi (Brazil) in 2015 and 2016, from daily questionnaires with eight questions answered by 114 people between 3 to 5 weeks per building, twice a day (10 a.m. and 3 p.m.). The paper analyses 6 out of 8 questions, emphasizing on the perception of temperature, humidity, and air movement. Statistics analyses were made crossing participant answers and humidity and temperature data related to time high time resolution time. Analyses were made from regressions comparing: internal and external temperature, and then compared with the answers of the participants. The results were put in graphics combining statistic graphics related to temperature and air humidity with the answers of the real occupants. Analysis related to the perception of the participants to humidity and air movements were also analyzed. The hygrothermal comfort statistic model of the European standard DIN EN 15251 and that from the Brazilian standard NBR 16401 were compared taking into account the perceptions of the hygrothermal comfort of the participants, with emphasis on air humidity, taking basis on prior studies published on this same research. The studies point out a relative tolerance for higher temperatures than the ones determined by the standards, besides a variation on the participants' perception concerning air humidity. The paper presents a group of detailed information that permits to improve the quality of the buildings based on the perception of occupants of the office buildings, contributing to the energy reduction without health damages and demands of necessary hygrothermal comfort, reducing the consumption of electricity on cooling.

Keywords: thermal comfort, energy consumption, energy standards, comfort models

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985 The 'Toshi-No-Sakon' Phenomenon: A Trend in Japanese Family Formations

Authors: Franco Lorenzo D. Morales

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‘Toshi-no-sakon,’ which translates to as ‘age gap marriage,’ is a term that has been popularized by celebrity couples in the Japanese entertainment industry. Japan is distinct for a developed nation for its rapidly aging population, declining marital and fertility rates, and the reinforcement of traditional gender roles. Statistical data has shown that the average age of marriage in Japan is increasing every year, showing a growing tendency for late marriage. As a result, the government has been trying to curb the declining trends by encouraging marriage and childbirth among the populace. This graduate thesis seeks to analyze the ‘toshi-no-sakon’ phenomenon in lieu of Japan’s current economic and social situation, and to see what the implications are for these kinds of married couples. This research also seeks to expound more on age gaps within married couples, which is a factor rarely-touched upon in Japanese family studies. A literature review was first performed in order to provide a framework to study ‘toshi-no-sakon’ from the perspective of four fields of study—marriage, family, aging, and gender. Numerous anonymous online statements by ‘toshi-no-sakon’ couples were then collected and analyzed, which brought to light a number of concerns. Couples wherein the husband is the older partner were prioritized in order to narrow down the focus of the research, and ‘toshi-no-sakon’ is only considered when the couple’s age gap is ten years or more. Current findings suggest that one of the perceived merits for a woman to marry an older man is that financial security would be guaranteed. However, this has been shown to be untrue as a number of couples express concern regarding their financial situation, which could be attributed to their husband’s socio-economic status. Having an older husband who is approaching the age of retirement presents another dilemma as the wife would be more obliged to provide care for her aging husband. This notion of the wife being a caregiver likely stems from an arrangement once common in Japanese families in which the wife must primarily care for her husband’s elderly parents. Childbearing is another concern as couples would be pressured to have a child right away due to the age of the husband, in addition to limiting the couple’s ideal number of children. This is another problematic aspect as the husband would have to provide income until his child has finished their education, implying that retirement would have to be delayed indefinitely. It is highly recommended that future studies conduct face-to-face interviews with couples and families who fall under the category of ‘toshi-no-sakon’ in order to gain a more in-depth perspective into the phenomenon and to reveal any undiscovered trends. Cases wherein the wife is the older partner in the relationship should also be given focus in future studies involving ‘toshi-no-sakon’.

Keywords: age gap, family structure, gender roles, marriage trends

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984 Risk Assessment on New Bio-Composite Materials Made from Water Resource Recovery

Authors: Arianna Nativio, Zoran Kapelan, Jan Peter van der Hoek

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Bio-composite materials are becoming increasingly popular in various applications, such as the automotive industry. Usually, bio-composite materials are made from natural resources recovered from plants, now, a new type of bio-composite material has begun to be produced in the Netherlands. This material is made from resources recovered from drinking water treatments (calcite), wastewater treatment (cellulose), and material from surface water management (aquatic plants). Surface water, raw drinking water, and wastewater can be contaminated with pathogens and chemical compounds. Therefore, it would be valuable to develop a framework to assess, monitor, and control the potential risks. Indeed, the goal is to define the major risks in terms of human health, quality of materials, and environment associated with the production and application of these new materials. This study describes the general risk assessment framework, starting with a qualitative risk assessment. The qualitative risk analysis was carried out by using the HAZOP methodology for the hazard identification phase. The HAZOP methodology is logical and structured and able to identify the hazards in the first stage of the design when hazards and associated risks are not well known. The identified hazards were analyzed to define the potential associated risks, and then these were evaluated by using the qualitative Event Tree Analysis. ETA is a logical methodology used to define the consequences for a specific hazardous incidents, evaluating the failure modes of safety barriers and dangerous intermediate events that lead to the final scenario (risk). This paper shows the effectiveness of combining of HAZOP and qualitative ETA methodologies for hazard identification and risk mapping. Then, key risks were identified, and a quantitative framework was developed based on the type of risks identified, such as QMRA and QCRA. These two models were applied to assess human health risks due to the presence of pathogens and chemical compounds such as heavy metals into the bio-composite materials. Thus, due to these contaminations, the bio-composite product, during its application, might release toxic substances into the environment leading to a negative environmental impact. Therefore, leaching tests are going to be planned to simulate the application of these materials into the environment and evaluate the potential leaching of inorganic substances, assessing environmental risk.

Keywords: bio-composite, risk assessment, water reuse, resource recovery

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983 Forecasting Regional Data Using Spatial Vars

Authors: Taisiia Gorshkova

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Since the 1980s, spatial correlation models have been used more often to model regional indicators. An increasingly popular method for studying regional indicators is modeling taking into account spatial relationships between objects that are part of the same economic zone. In 2000s the new class of model – spatial vector autoregressions was developed. The main difference between standard and spatial vector autoregressions is that in the spatial VAR (SpVAR), the values of indicators at time t may depend on the values of explanatory variables at the same time t in neighboring regions and on the values of explanatory variables at time t-k in neighboring regions. Thus, VAR is a special case of SpVAR in the absence of spatial lags, and the spatial panel data model is a special case of spatial VAR in the absence of time lags. Two specifications of SpVAR were applied to Russian regional data for 2000-2017. The values of GRP and regional CPI are used as endogenous variables. The lags of GRP, CPI and the unemployment rate were used as explanatory variables. For comparison purposes, the standard VAR without spatial correlation was used as “naïve” model. In the first specification of SpVAR the unemployment rate and the values of depending variables, GRP and CPI, in neighboring regions at the same moment of time t were included in equations for GRP and CPI respectively. To account for the values of indicators in neighboring regions, the adjacency weight matrix is used, in which regions with a common sea or land border are assigned a value of 1, and the rest - 0. In the second specification the values of depending variables in neighboring regions at the moment of time t were replaced by these values in the previous time moment t-1. According to the results obtained, when inflation and GRP of neighbors are added into the model both inflation and GRP are significantly affected by their previous values, and inflation is also positively affected by an increase in unemployment in the previous period and negatively affected by an increase in GRP in the previous period, which corresponds to economic theory. GRP is not affected by either the inflation lag or the unemployment lag. When the model takes into account lagged values of GRP and inflation in neighboring regions, the results of inflation modeling are practically unchanged: all indicators except the unemployment lag are significant at a 5% significance level. For GRP, in turn, GRP lags in neighboring regions also become significant at a 5% significance level. For both spatial and “naïve” VARs the RMSE were calculated. The minimum RMSE are obtained via SpVAR with lagged explanatory variables. Thus, according to the results of the study, it can be concluded that SpVARs can accurately model both the actual values of macro indicators (particularly CPI and GRP) and the general situation in the regions

Keywords: forecasting, regional data, spatial econometrics, vector autoregression

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982 Walking the Talk? Thinking and Acting – Teachers' and Practitioners' Perceptions about Physical Activity, Health and Well-Being, Do They 'Walk the Talk' ?

Authors: Kristy Howells, Catherine Meehan

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This position paper presents current research findings into the proposed gap between teachers’ and practitioners’ thinking and acting about physical activity health and well-being in childhood. Within the new Primary curriculum, there is a focus on sustained physical activity within a Physical Education and healthy lifestyles in Personal, Health, Social and Emotional lessons, but there is no curriculum guidance about what sustained physical activity is and how it is defined. The current health guidance on birth to five suggests that children should not be inactive for long periods and specify light and energetic activities, however there is the a suggested period of time per day for young children to achieve, but the guidance does not specify how this should be measured. The challenge therefore for teachers and practitioners is their own confidence and understanding of what “good / moderate intensity” physical activity and healthy living looks like for children and the children understanding what they are doing. There is limited research about children from birth to eight years and also the perceptions and attitudes of those who work with this age group of children, however it was found that children at times can identify different levels of activity and it has been found that children can identify healthy foods and good choices for healthy living at a basic level. Authors have also explored teachers’ beliefs about teaching and learning and found that teachers could act in accordance to their beliefs about their subject area only when their subject knowledge, understanding and confidence of that area is high. It has been proposed that confidence and competence of practitioners and teachers to integrate ‘well-being’ within the learning settings has been reported as being low. This may be due to them not having high subject knowledge. It has been suggested that children’s life chances are improved by focusing on well-being in their earliest years. This includes working with parents and families, and being aware of the environmental contexts that may impact on children’s wellbeing. The key is for practitioners and teachers to know how to implement these ideas effectively as these key workers have a profound effect on young children as role models and due to the time of waking hours spent with them. The position paper is part of a longitudinal study at Canterbury Christ Church University and currently we will share the research findings from the initial questionnaire (online, postal, and in person) that explored and evaluated the knowledge, competence and confidence levels of practitioners and teachers as to the structure and planning of sustained physical activity and healthy lifestyles and how this progresses with the children’s age.

Keywords: health, perceptions, physical activity, well-being

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981 Professional Development in EFL Classroom: Motivation and Reflection

Authors: Iman Jabbar

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Within the scope of professionalism and in order to compete with the modern world, teachers, are expected to develop their teaching skills and activities in addition to their professional knowledge. At the college level, the teacher should be able to face classroom challenges through his engagement with the learning situation to understand the students and their needs. In our field of TESOL, the role of the English teacher is no longer restricted to teaching English texts, but rather he should endeavor to enhance the students’ skills such as communication and critical analysis. Within the literature of professionalism, there are certain strategies and tools that an English teacher should adopt to develop his competence and performance. Reflective practice, which is an exploratory process, is one of these strategies. Another strategy contributing to classroom development is motivation. It is crucial in students’ learning as it affects the quality of learning English in the classroom in addition to determining success or failure as well as language achievement. This is a qualitative study grounded on interpretive perspectives of teachers and students regarding the process of professional development. This study aims at (a) understanding how teachers at the college level conceptualize reflective practice and motivation inside EFL classroom, and (b) exploring the methods and strategies that they implement to practice reflection and motivation. This study and is based on two questions: 1. How do EFL teachers perceive and view reflection and motivation in relation to their teaching and professional development? 2. How can reflective practice and motivation be developed into practical strategies and actions in EFL teachers’ professional context? The study is organized into two parts, theoretical and practical. The theoretical part reviews the literature on the concept of reflective practice and motivation in relation to professional development through providing certain definitions, theoretical models, and strategies. The practical part draws on the theoretical one, however; it is the core of the study since it deals with two issues. It involves the research design, methodology, and methods of data collection, sampling, and data analysis. It ends up with an overall discussion of findings and the researcher's reflections on the investigated topic. In terms of significance, the study is intended to contribute to the field of TESOL at the academic level through the selection of the topic and investigating it from theoretical and practical perspectives. Professional development is the path that leads to enhancing the quality of teaching English as a foreign or second language in a way that suits the modern trends of globalization and advanced technology.

Keywords: professional development, motivation, reflection, learning

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980 Influence of Synergistic Modification with Tung Oil and Heat Treatment on Physicochemical Properties of Wood

Authors: Luxi He, Tianfang Zhang, Zhengbin He, Songlin Yi

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Heat treatment has been widely recognized for its effectiveness in enhancing the physicochemical properties of wood, including hygroscopicity and dimensional stability. Nonetheless, the non-negligible volumetric shrinkage and loss of mechanical strength resulting from heat treatment may diminish the wood recovery and its product value. In this study, tung oil was used to alleviate heat-induced shrinkage and reduction in mechanical properties of wood during heat treatment. Tung oil was chosen as a modifier because it is a traditional Chinese plant oil that has been widely used for over a thousand years to protect wooden furniture and buildings due to its biodegradable and non-toxic properties. The effects of different heating media (air, tung oil) and their effective treatment parameters (temperature, duration) on the changes in the physical properties (morphological characteristics, pore structures, micromechanical properties), and chemical properties (chemical structures, chemical composition) of wood were investigated by using scanning electron microscopy, confocal laser scanning microscopy, atomic force microscopy, X-ray photoelectron spectroscopy, and dynamic vapor sorption. Meanwhile, the correlation between the mass changes and the color change, volumetric shrinkage, and hygroscopicity was also investigated. The results showed that the thermal degradation of wood cell wall components was the most important factor contributing to the changes in heat-induced shrinkage, color, and moisture adsorption of wood. In air-heat-treated wood samples, there was a significant correlation between mass change and heat-induced shrinkage, brightness, and moisture adsorption. However, the presence of impregnated tung oil in oil-heat-treated wood appears to disrupt these correlations among physical properties. The results of micromechanical properties demonstrated a significant decrease in elastic modulus following high-temperature heat treatment, which was mitigated by tung oil treatment. Chemical structure and compositional analyses indicated that the changes in chemical structure primarily stem from the degradation of hemicellulose and cellulose, and the presence of tung oil created an oxygen-insulating environment that slowed down this degradation process. Morphological observation results showed that tung oil permeated the wood structure and penetrated the cell walls through transportation channels, altering the micro-morphology of the cell wall surface, obstructing primary water passages (e.g., vessels and pits), and impeding the release of volatile degradation products as well as the infiltration and diffusion of water. In summary, tung oil treatment represents an environmentally friendly and efficient method for maximizing wood recovery and increasing product value. This approach holds significant potential for industrial applications in wood heat treatment.

Keywords: tung oil, heat treatment, physicochemical properties, wood cell walls

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979 Item-Trait Pattern Recognition of Replenished Items in Multidimensional Computerized Adaptive Testing

Authors: Jianan Sun, Ziwen Ye

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Multidimensional computerized adaptive testing (MCAT) is a popular research topic in psychometrics. It is important for practitioners to clearly know the item-trait patterns of administered items when a test like MCAT is operated. Item-trait pattern recognition refers to detecting which latent traits in a psychological test are measured by each of the specified items. If the item-trait patterns of the replenished items in MCAT item pool are well detected, the interpretability of the items can be improved, which can further promote the abilities of the examinees who attending the MCAT to be accurately estimated. This research explores to solve the item-trait pattern recognition problem of the replenished items in MCAT item pool from the perspective of statistical variable selection. The popular multidimensional item response theory model, multidimensional two-parameter logistic model, is assumed to fit the response data of MCAT. The proposed method uses the least absolute shrinkage and selection operator (LASSO) to detect item-trait patterns of replenished items based on the essential information of item responses and ability estimates of examinees collected from a designed MCAT procedure. Several advantages of the proposed method are outlined. First, the proposed method does not strictly depend on the relative order between the replenished items and the selected operational items, so it allows the replenished items to be mixed into the operational items in reasonable order such as considering content constraints or other test requirements. Second, the LASSO used in this research improves the interpretability of the multidimensional replenished items in MCAT. Third, the proposed method can exert the advantage of shrinkage method idea for variable selection, so it can help to check item quality and key dimension features of replenished items and saves more costs of time and labors in response data collection than traditional factor analysis method. Moreover, the proposed method makes sure the dimensions of replenished items are recognized to be consistent with the dimensions of operational items in MCAT item pool. Simulation studies are conducted to investigate the performance of the proposed method under different conditions for varying dimensionality of item pool, latent trait correlation, item discrimination, test lengths and item selection criteria in MCAT. Results show that the proposed method can accurately detect the item-trait patterns of the replenished items in the two-dimensional and the three-dimensional item pool. Selecting enough operational items from the item pool consisting of high discriminating items by Bayesian A-optimality in MCAT can improve the recognition accuracy of item-trait patterns of replenished items for the proposed method. The pattern recognition accuracy for the conditions with correlated traits is better than those with independent traits especially for the item pool consisting of comparatively low discriminating items. To sum up, the proposed data-driven method based on the LASSO can accurately and efficiently detect the item-trait patterns of replenished items in MCAT.

Keywords: item-trait pattern recognition, least absolute shrinkage and selection operator, multidimensional computerized adaptive testing, variable selection

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978 An Investigation into the Influence of Compression on 3D Woven Preform Thickness and Architecture

Authors: Calvin Ralph, Edward Archer, Alistair McIlhagger

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3D woven textile composites continue to emerge as an advanced material for structural applications and composite manufacture due to their bespoke nature, through thickness reinforcement and near net shape capabilities. When 3D woven preforms are produced, they are in their optimal physical state. As 3D weaving is a dry preforming technology it relies on compression of the preform to achieve the desired composite thickness, fibre volume fraction (Vf) and consolidation. This compression of the preform during manufacture results in changes to its thickness and architecture which can often lead to under-performance or changes of the 3D woven composite. Unlike traditional 2D fabrics, the bespoke nature and variability of 3D woven architectures makes it difficult to know exactly how each 3D preform will behave during processing. Therefore, the focus of this study is to investigate the effect of compression on differing 3D woven architectures in terms of structure, crimp or fibre waviness and thickness as well as analysing the accuracy of available software to predict how 3D woven preforms behave under compression. To achieve this, 3D preforms are modelled and compression simulated in Wisetex with varying architectures of binder style, pick density, thickness and tow size. These architectures have then been woven with samples dry compression tested to determine the compressibility of the preforms under various pressures. Additional preform samples were manufactured using Resin Transfer Moulding (RTM) with varying compressive force. Composite samples were cross sectioned, polished and analysed using microscopy to investigate changes in architecture and crimp. Data from dry fabric compression and composite samples were then compared alongside the Wisetex models to determine accuracy of the prediction and identify architecture parameters that can affect the preform compressibility and stability. Results indicate that binder style/pick density, tow size and thickness have a significant effect on compressibility of 3D woven preforms with lower pick density allowing for greater compression and distortion of the architecture. It was further highlighted that binder style combined with pressure had a significant effect on changes to preform architecture where orthogonal binders experienced highest level of deformation, but highest overall stability, with compression while layer to layer indicated a reduction in fibre crimp of the binder. In general, simulations showed a relative comparison to experimental results; however, deviation is evident due to assumptions present within the modelled results.

Keywords: 3D woven composites, compression, preforms, textile composites

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977 Assessment of Water Pollution in the River Nile (Egypt) by Applying Blood Biomarkers in Two Excellent Model Species Oreochromis niloticus niloticus and Clarias gariepinus

Authors: Alaa G. M. Osman, Abd-El –Baset M. Abd El Reheem, Khaled Y. Abouelfadl, Usama M. Mahmoud, Mohsen A. Moustafa

Abstract:

This study aimed to explore new sites of biomarker research and to establish the use of blood parameters in wild fish populations. Four hundred and twenty fish samples were collected from six sites along the whole course of the river Nile, Egypt. The mean values of erythrocytes, thrombocytes, hemoglobin concentration, hematocrit value, and mean corpuscular volume were significantly lower in the blood of Nile tilapia and African catfish collected from downstream (contaminated) compared to upstream sites. In contrast, mean corpuscular hemoglobin and mean corpuscular hemoglobin concentration in the peripheral blood of both fish species significantly increased from upstream to downstream river Nile. The leukocytes count was significantly decreased in contaminated sites compared to upstream area. Hematological variables in the peripheral blood of Oreochromis niloticus niloticus and Clarias gariepinus exhibited significant (p<0.05) correlation with nearly all the detected chemical and physical parameters along the Nile course. In the present study, lower cellular and nuclear areas and cellular and nuclear shape factor were recorded in the erythrocytes of fish collected from downstream compared to those caught from upstream sites. This was confirmed by higher immature ratios of red cells in the blood of fish sampled from downstream river Nile. Karyorrhetic and enucleated erythrocytes were significantly correlated with physiochemical parameters in water samples collected from the same sites is being higher in the blood of fish collected from downstream sites. To see if there was any correlation between fish altered physiological fitness and environmental stress, we measured serum biochemical variables namely; total protein, cholesterol, triglycerides, calcium, chlorides, alkaline phosphatase activity (ALP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), uric acid activity, creatinine, and serum glucose. The level of all the selected biochemical variables in the blood of O. niloticus niloticus and C. gariepinus were recorded to be significantly higher (p<0.05) in downstream sites. According to the present results, nearly all the detected haematological and blood biochemical variables are suitable indicators of contaminant exposure in O. niloticus niloticus and C. gariepinus. Also the detected erythrocytes malformations in blood collected from Nile tilapia and African catfish were proven to be suitable for bio-monitoring aquatic pollution. The results revealed species-specific differences in sensitivities, suggesting that Nile tilapia may serve as a more sensitive test species compared to African catfish.

Keywords: biomarkers, water pollution, blood parameters, river nile, african catfish, nile tilapia

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976 Life Satisfaction of Non-Luxembourgish and Native Luxembourgish Postgraduate Students

Authors: Chrysoula Karathanasi, Senad Karavdic, Angela Odero, Michèle Baumann

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It is not only the economic determinants that impact on life conditions, but maintaining a good level of life satisfaction (LS) may also be an important challenge currently. In Luxembourg, university students receive financial aid from the government. They are then registered at the Centre for Documentation and Information on Higher Education (CEDIES). Luxembourg is built on migration with almost half its population consisting of foreigners. It is upon this basis that our research aims to analyze the associations with mental health factors (health satisfaction, psychological quality of life, worry), perceived financial situation, career attitudes (adaptability, optimism, knowledge, planning) and LS, for non-Luxembourgish and native postgraduate students. Between 2012 and 2013, postgraduates registered at CEDIES were contacted by post and asked to participate in an online survey with either the option of English or French. The study population comprised of 644 respondents. Our statistical analysis excluded: those born abroad who had Luxembourgish citizenship, or those born in Luxembourg who did not have citizenship. Two groups were formed one consisting 147 non-Luxembourgish and the other 284 natives. A single item measured LS (1=not at all satisfied to 10=very satisfied). Bivariate tests, correlations and multiple linear regression models were used in which only significant relationships (p<0.05) were integrated. Among the two groups no differences were found between LS indicators (7.8/10 non-Luxembourgish; 8.0/10 natives) as both were higher than the European indicator of 7.2/10 (for 25-34 years). In the case of non-Luxembourgish students, they were older than natives (29.3 years vs. 26.3 years) perceived their financial situation as more difficult, and a higher percentage of their parents had an education level higher than a Bachelor's degree (father 59.2% vs 44.6% for natives; mother 51.4% vs 33.7% for natives). In addition, the father’s education was related to the LS of postgraduates and the higher was the score, the greater was the contribution to LS. Whereas for native students, when their scores of health satisfaction and career optimism were higher, their LS’ score was higher. For both groups their LS was linked to mental health-related factors, perception of their financial situation, career optimism, adaptability and planning. The higher the psychological quality of life score was, the greater the LS of postgraduates’ was. Good health and positive attitudes related to the job market enhanced their LS indicator.

Keywords: career attributes, father's education level, life satisfaction, mental health

Procedia PDF Downloads 361
975 Network Based Speed Synchronization Control for Multi-Motor via Consensus Theory

Authors: Liqin Zhang, Liang Yan

Abstract:

This paper addresses the speed synchronization control problem for a network-based multi-motor system from the perspective of cluster consensus theory. Each motor is considered as a single agent connected through fixed and undirected network. This paper presents an improved control protocol from three aspects. First, for the purpose of improving both tracking and synchronization performance, this paper presents a distributed leader-following method. The improved control protocol takes the importance of each motor’s speed into consideration, and all motors are divided into different groups according to speed weights. Specifically, by using control parameters optimization, the synchronization error and tracking error can be regulated and decoupled to some extent. The simulation results demonstrate the effectiveness and superiority of the proposed strategy. In practical engineering, the simplified models are unrealistic, such as single-integrator and double-integrator. And previous algorithms require the acceleration information of the leader available to all followers if the leader has a varying velocity, which is also difficult to realize. Therefore, the method focuses on an observer-based variable structure algorithm for consensus tracking, which gets rid of the leader acceleration. The presented scheme optimizes synchronization performance, as well as provides satisfactory robustness. What’s more, the existing algorithms can obtain a stable synchronous system; however, the obtained stable system may encounter some disturbances that may destroy the synchronization. Focus on this challenging technological problem, a state-dependent-switching approach is introduced. In the presence of unmeasured angular speed and unknown failures, this paper investigates a distributed fault-tolerant consensus tracking algorithm for a group non-identical motors. The failures are modeled by nonlinear functions, and the sliding mode observer is designed to estimate the angular speed and nonlinear failures. The convergence and stability of the given multi-motor system are proved. Simulation results have shown that all followers asymptotically converge to a consistent state when one follower fails to follow the virtual leader during a large enough disturbance, which illustrates the good performance of synchronization control accuracy.

Keywords: consensus control, distributed follow, fault-tolerant control, multi-motor system, speed synchronization

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974 The Acquisition of /r/ By Setswana-Learning Children

Authors: Keneilwe Matlhaku

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Crosslinguistic studies (theoretical and clinical) have shown delays and significant misarticulation in the acquisition of the rhotics. This article provides a detailed analysis of the early development of the rhotic phoneme, an apical trill /r/, by monolingual Setswana (Tswana S30) children of age ranges between 1 and 4 years. The data display the following trends: (1) late acquisition of /r/; (2) a wide range of substitution patterns involving this phoneme (i.e., gliding, coronal stopping, affrication, deletion, lateralization, as well as, substitution to a dental and uvular fricative). The primary focus of the article is on the potential origins of these variations of /r/, even within the same language. Our data comprises naturalistic longitudinal audio recordings of 6 children (2 males and 4 females) whose speech was recorded in their homes over a period of 4 months with no or only minimal disruptions in their daily environments. Phon software (Rose et al. 2013; Rose & MacWhinney 2014) was used to carry out the orthographic and phonetic transcriptions of the children’s data. Phon also enabled the generation of the children’s phonological inventories for comparison with adult target IPA forms. We explain the children’s patterns through current models of phonological emergence (MacWhinney 2015) as well as McAllister Byun, Inkelas & Rose (2016); Rose et al., (2022), which highlight the perceptual and articulatory factors influencing the development of sounds and sound classes. We highlight how the substitution patterns observed in the data can be captured through a consideration of the auditory properties of the target speech sounds, combined with an understanding of the types of articulatory gestures involved in the production of these sounds. These considerations, in turn, highlight some of the most central aspects of the challenges faced by the child toward learning these auditory-articulatory mappings. We provide a cross-linguistic survey of the acquisition of rhotic consonants in a sample of related and unrelated languages in which we show that the variability and volatility in the substitution patterns of /r/ is also brought about by the properties of the children’s ambient languages. Beyond theoretical issues, this article sets an initial foundation for developing speech-language pathology materials and services for Setswana learning children, an emerging area of public service in Botswana.

Keywords: rhotic, apical trill, Phon, phonological emergence, auditory, articulatory, mapping

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973 Sources and Content of Sexual Information among School Going Adolescents in Uganda

Authors: Jonathan Magala

Abstract:

Context: Adolescents in Uganda face significant challenges related to sexual health due to inadequate sexual information. This lack of information puts young people at risk of early pregnancies, sexually transmitted infections, and poverty. Therefore, it is essential to understand the sources, content, and challenges of acquiring sexual information among secondary school-going adolescents in Uganda. Research Aim: The aim of this study was to establish the sources, content, and challenges of acquiring sexual information among secondary school-going adolescents in Luwero Town Council, Uganda. Methodology: This study used a cross-sectional approach with both qualitative and quantitative methods. Questionnaires and in-depth interviews were conducted with 384 school-going adolescents aged between 13-19 years in Luwero Town Council, Uganda. Findings: The results of the study revealed that adolescents receive sexual information from various sources, with schools being the most common source, followed by parents and religious institutions being the least utilized. Adolescents received information on various topics related to sexuality, including puberty and sexual changes, pregnancy and reproduction, STD information, abstinence, and family planning. However, the content of sexual information was inadequate in addressing the challenges facing adolescents, and there were generation gaps, lack of role models, peer influence, and government policies. The male character from all the sources was the least in offering sexual information to adolescents. Theoretical Importance: The study's findings highlight the need for policy implementation to strengthen sexual education in school curriculum, as the sources of sexual information and the content are inadequate. The various topics should be addressed in schools to provide comprehensive education on sexual health for adolescents. Data Collection and Analysis Procedures: Data collection involved questionnaires and in-depth interviews with school-going adolescents. The data gathered were analyzed using descriptive statistics and thematic analysis. Questions Addressed: The study aimed to answer questions about the sources of sexual information among school-going adolescents, the content of sexual information provided, the challenges faced in accessing the information, and the importance of sex education policy implementation. Conclusion: The study concludes that schools are a popular source of sexual information among school-going adolescents in Uganda. However, the content of the information provided is inadequate in addressing the challenges that adolescents face regarding their sexual health. Therefore, policy implementation is essential in strengthening sexual education in the school curriculum and addressing various topics related to sexual health.

Keywords: adolescents, sexual information, schools, reproductive health

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972 Characterization of Phenolic Compounds from Carménère Wines during Aging with Oak Wood (Staves, Chips and Barrels)

Authors: E. Obreque-Slier, J. Laqui-Estaña, A. Peña-Neira, M. Medel-Marabolí

Abstract:

Wine is an important source of polyphenols. Red wines show important concentrations of nonflavonoid (gallic acid, ellagic acid, caffeic acid and coumaric acid) and flavonoid compounds [(+)-catechin, (-)-epicatechin, (+)-gallocatechin and (-)-epigallocatechin]. However, a significant variability in the quantitative and qualitative distribution of chemical constituents in wine has to be expected depending on an array of important factors, such as the varietal differences of Vitis vinifera and cultural practices. It has observed that Carménère grapes present a differential composition and evolution of phenolic compounds when compared to other varieties and specifically with Cabernet Sauvignon grapes. Likewise, among the cultural practices, the aging in contact with oak wood is a high relevance factor. Then, the extraction of different polyphenolic compounds from oak wood into wine during its ageing process produces both qualitative and quantitative changes. Recently, many new techniques have been introduced in winemaking. One of these involves putting new pieces of wood (oak chips or inner staves) into inert containers. It offers some distinct and previously unavailable flavour advantages, as well as new options in wine handling. To our best knowledge, there is not information about the behaviour of Carménère wines (Chilean emblematic cultivar) in contact with oak wood. In addition, the effect of aging time and wood product (barrels, chips or staves) on the phenolic composition in Carménère wines has not been studied. This study aims at characterizing the condensed and hydrolyzable tannins from Carménère wines during the aging with staves, chips and barrels from French oak wood. The experimental design was completely randomized with two independent assays: aging time (0-12 month) and different formats of wood (barrel, chips and staves). The wines were characterized by spectrophotometric (total tannins and fractionation of proanthocyanidins into monomers, oligomers and polymers) and HPLC-DAD (ellagitannins) analysis. The wines in contact with different products of oak wood showed a similar content of total tannins during the study, while the control wine (without oak wood) presented a lower content of these compounds. In addition, it was observed that the polymeric proanthocyanidin fraction was the most abundant, while the monomeric fraction was the less abundant fraction in all treatments in two sample. However, significative differences in each fractions were observed between wines in contact from barrel, chips, and staves in two sample dates. Finally, the wine from barrels presented the highest content of the ellagitannins from the fourth to the last sample date. In conclusion, the use of alternative formats of oak wood affects the chemical composition of wines during aging, and these enological products are an interesting alternative to contribute with tannins to wine.

Keywords: enological inputs, oak wood aging, polyphenols, red wine

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971 Austrian Secondary School Teachers’ Perspectives on Character Education and Life Skills: First Quantitative Insights from a Mixed Methods Study

Authors: Evelyn Kropfreiter, Roland Bernhard

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There has been an increased interest in school-based whole-child development in the Austrian education system in the last few years. Although there is a consensus among academics that teachers' beliefs are an essential component of their professional competence, there are hardly any studies in the German-speaking world examining teachers' beliefs about school-based character education. To close this gap, we are conducting a mixed methods study combining qualitative interviews and a questionnaire in Austria (doctoral thesis at the University of Salzburg). In this paper, we present preliminary insights into the quantitative strand of the project. In contrast to German-speaking countries, the Anglo-Saxon world has a long tradition of explicit character education in schools. There has been a rising interest in approaches focusing on a neo-Aristotelian form of character education in England. The Jubilee Centre strongly influences the "renaissance" of papers on neo-Aristotelian character education for Character and Virtues, founded in 2012. The quantitative questionnaire study (n = 264) is an online survey of teachers and school principals conducted in four different federal states in spring 2023. Most respondents (n = 264) from lower secondary schools (AHS-Unterstufe and Mittelschule) believe that character education in schools for 10-14-year-olds is more important for society than good exam results. Many teachers state that they consider themselves prepared to promote their students' personal development and life skills through their education and to attend further training courses. However, there are many obstacles in the education system to ensure that a comprehensive education reaches the students. Many teachers state that they consider themselves prepared to promote their students' character strengths and life skills through their education and to attend further training courses. However, there are many obstacles in the education system to ensure that a comprehensive education reaches the students. Among the most cited difficulties, teachers mention the time factor associated with an overcrowded curriculum and a strong focus on performance, which often leaves them needing more time to keep an eye on nurturing the whole person. The fact that character education is not a separate subject, and its implementation needs to be monitored also makes it challenging to implement it in everyday school life. Austrian teachers prioritize moral virtues such as compassion and honesty as character strengths in everyday school life and resilience and commitment in the next place. Our results are like those reported in other studies on teacher's beliefs about character education. They indicate that Austrian teachers want to teach character in their schools but see systemic constraints such as the curriculum, in which personality roles play a subordinate role, and the focus on performance testing in the school system and the associated lack of time as obstacles to fostering more character development in students.

Keywords: character education, life skills, teachers' beliefs, virtues

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970 Hybrid Knowledge and Data-Driven Neural Networks for Diffuse Optical Tomography Reconstruction in Medical Imaging

Authors: Paola Causin, Andrea Aspri, Alessandro Benfenati

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Diffuse Optical Tomography (DOT) is an emergent medical imaging technique which employs NIR light to estimate the spatial distribution of optical coefficients in biological tissues for diagnostic purposes, in a noninvasive and non-ionizing manner. DOT reconstruction is a severely ill-conditioned problem due to prevalent scattering of light in the tissue. In this contribution, we present our research in adopting hybrid knowledgedriven/data-driven approaches which exploit the existence of well assessed physical models and build upon them neural networks integrating the availability of data. Namely, since in this context regularization procedures are mandatory to obtain a reasonable reconstruction [1], we explore the use of neural networks as tools to include prior information on the solution. 2. Materials and Methods The idea underlying our approach is to leverage neural networks to solve PDE-constrained inverse problems of the form 𝒒 ∗ = 𝒂𝒓𝒈 𝒎𝒊𝒏𝒒 𝐃(𝒚, 𝒚̃), (1) where D is a loss function which typically contains a discrepancy measure (or data fidelity) term plus other possible ad-hoc designed terms enforcing specific constraints. In the context of inverse problems like (1), one seeks the optimal set of physical parameters q, given the set of observations y. Moreover, 𝑦̃ is the computable approximation of y, which may be as well obtained from a neural network but also in a classic way via the resolution of a PDE with given input coefficients (forward problem, Fig.1 box ). Due to the severe ill conditioning of the reconstruction problem, we adopt a two-fold approach: i) we restrict the solutions (optical coefficients) to lie in a lower-dimensional subspace generated by auto-decoder type networks. This procedure forms priors of the solution (Fig.1 box ); ii) we use regularization procedures of type 𝒒̂ ∗ = 𝒂𝒓𝒈𝒎𝒊𝒏𝒒 𝐃(𝒚, 𝒚̃)+ 𝑹(𝒒), where 𝑹(𝒒) is a regularization functional depending on regularization parameters which can be fixed a-priori or learned via a neural network in a data-driven modality. To further improve the generalizability of the proposed framework, we also infuse physics knowledge via soft penalty constraints (Fig.1 box ) in the overall optimization procedure (Fig.1 box ). 3. Discussion and Conclusion DOT reconstruction is severely hindered by ill-conditioning. The combined use of data-driven and knowledgedriven elements is beneficial and allows to obtain improved results, especially with a restricted dataset and in presence of variable sources of noise.

Keywords: inverse problem in tomography, deep learning, diffuse optical tomography, regularization

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969 Spatial Setting in Translation: A Comparative Evaluation of translations from Pre-Islamic Poetry

Authors: Raja Lahiani

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This study is concerned with scrutinising translations into English and French of references to locations in the desert of pre-Islamic Arabia. These references are used in the Source Text (ST) within a poetic image. Reference is made to the names of three different mountains in Arabia, namely Qatan, Sitar, and Yadhbul. As these mountains are referred to in the context of the poet’s description of the density and expansion of the clouds, it is crucial to know that while Sitar and Yadhbul are close to each other, Qatan is far away from them. This distance was functional for the poet to describe the expansion of the clouds. This reflects the spacious place (desert) he handled, and the fact that it was possible for him to physically see what he described. The purpose of this image is for the poet to communicate the vastness of the space he managed to see as he was in a moment of contemplation. Thus, knowledge of this characteristic about the setting is capital for the receiver to understand the communicative function of the verse. A corpus of eighteen translations is gathered. These vary between verse and prose renderings. The methodology adopted in this research work is comparative. Comparison is conducted at both the synchronic and diachronic levels; every translation shall be compared to the ST and then to previous translations. The comparative work will prove at the end that the translators who target historical facts do not necessarily succeed in preserving the image of the ST. It also proves that the more recent the translation is, the deeper the translator’s awareness is the link between imagery, setting, and point of view. Since the late eighteenth century and until nowadays, pre-Islamic poetry has been translated into Western languages. Translators differ as to motives, sources, priorities and intellectual backgrounds. A translator's skopoi undoubtedly affect the way s/he handles aspects of the ST. When it comes to culture-specific aspects and details related to setting, the problem is even more complex. Setting is a very important factor that reveals a great deal of the culture of pre-Islamic Arabia as this is remote in place, historical framework and literary tradition from its translators. History is present in pre-Islamic poetry, which justifies the important literature that has been written to extract information and data from it. These are imbedded not only by signalling given facts, events, and meditations but also by means of references to specific locations and landmarks that used to exist at the time. Spatial setting is an integral part of a literary text as it places it within its historical context. The importance of the translator’s awareness of spatial anthropological data before indulging in the process of translation is tested. This is also crucial in measuring the effect of setting loss and setting gain in translation. The findings of this research would ultimately evaluate the extent to which a comparative methodology is reliable in investigating the role of spatial setting awareness in translation.

Keywords: historical context, translation, comparative literature, spatial setting

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968 Hardware Implementation on Field Programmable Gate Array of Two-Stage Algorithm for Rough Set Reduct Generation

Authors: Tomasz Grzes, Maciej Kopczynski, Jaroslaw Stepaniuk

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The rough sets theory developed by Prof. Z. Pawlak is one of the tools that can be used in the intelligent systems for data analysis and processing. Banking, medicine, image recognition and security are among the possible fields of utilization. In all these fields, the amount of the collected data is increasing quickly, but with the increase of the data, the computation speed becomes the critical factor. Data reduction is one of the solutions to this problem. Removing the redundancy in the rough sets can be achieved with the reduct. A lot of algorithms of generating the reduct were developed, but most of them are only software implementations, therefore have many limitations. Microprocessor uses the fixed word length, consumes a lot of time for either fetching as well as processing of the instruction and data; consequently, the software based implementations are relatively slow. Hardware systems don’t have these limitations and can process the data faster than a software. Reduct is the subset of the decision attributes that provides the discernibility of the objects. For the given decision table there can be more than one reduct. Core is the set of all indispensable condition attributes. None of its elements can be removed without affecting the classification power of all condition attributes. Moreover, every reduct consists of all the attributes from the core. In this paper, the hardware implementation of the two-stage greedy algorithm to find the one reduct is presented. The decision table is used as an input. Output of the algorithm is the superreduct which is the reduct with some additional removable attributes. First stage of the algorithm is calculating the core using the discernibility matrix. Second stage is generating the superreduct by enriching the core with the most common attributes, i.e., attributes that are more frequent in the decision table. Described above algorithm has two disadvantages: i) generating the superreduct instead of reduct, ii) additional first stage may be unnecessary if the core is empty. But for the systems focused on the fast computation of the reduct the first disadvantage is not the key problem. The core calculation can be achieved with a combinational logic block, and thus add respectively little time to the whole process. Algorithm presented in this paper was implemented in Field Programmable Gate Array (FPGA) as a digital device consisting of blocks that process the data in a single step. Calculating the core is done by the comparators connected to the block called 'singleton detector', which detects if the input word contains only single 'one'. Calculating the number of occurrences of the attribute is performed in the combinational block made up of the cascade of the adders. The superreduct generation process is iterative and thus needs the sequential circuit for controlling the calculations. For the research purpose, the algorithm was also implemented in C language and run on a PC. The times of execution of the reduct calculation in a hardware and software were considered. Results show increase in the speed of data processing.

Keywords: data reduction, digital systems design, field programmable gate array (FPGA), reduct, rough set

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967 Beyond Sexual Objectification: Moderation Analysis of Trauma and Overexcitability Dynamics in Women

Authors: Ritika Chaturvedi

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Introduction: Sexual objectification, characterized by the reduction of an individual to a mere object of sexual desire, remains a pervasive societal issue with profound repercussions on individual well-being. Such experiences, often rooted in systemic and cultural norms, have long-lasting implications for mental and emotional health. This study aims to explore the intricate relationship between experiences of sexual objectification and insidious trauma, further investigating the potential moderating effects of overexcitability as proposed by Dabrowski's theory of positive disintegration. Methodology: The research involved a comprehensive cohort of 204 women, spanning ages from 18 to 65 years. Participants were tasked with completing self-administered questionnaires designed to capture their experiences with sexual objectification. Additionally, the questionnaire assessed symptoms indicative of insidious trauma and explored overexcitability across five distinct domains: emotional, intellectual, psychomotor, sensory, and imaginational. Employing advanced statistical techniques, including multiple regression and moderation analysis, the study sought to decipher the intricate interplay among these variables. Findings: The study's results revealed a compelling positive correlation between experiences of sexual objectification and the onset of symptoms indicative of insidious trauma. This correlation underscores the profound and detrimental effects of sexual objectification on an individual's psychological well-being. Interestingly, the moderation analyses introduced a nuanced understanding, highlighting the differential roles of various overexcitability. Specifically, emotional, intellectual, and sensual overexcitability were found to exacerbate trauma symptomatology. In contrast, psychomotor overexcitability emerged as a protective factor, demonstrating a mitigating influence on the relationship between sexual objectification and trauma. Implications: The study's findings hold significant implications for a diverse array of stakeholders, encompassing mental health practitioners, educators, policymakers, and advocacy groups. The identified moderating effects of overexcitability emphasize the need for tailored interventions that consider individual differences in coping and resilience mechanisms. By recognizing the pivotal role of overexcitability in modulating the traumatic consequences of sexual objectification, this research advocates for the development of more nuanced and targeted support frameworks. Moreover, the study underscores the importance of continued research endeavors to unravel the intricate mechanisms and dynamics underpinning these relationships. Such endeavors are crucial for fostering the evolution of informed, evidence-based interventions and strategies aimed at mitigating the adverse effects of sexual objectification and promoting holistic well-being.

Keywords: sexual objectification, insidious trauma, emotional overexcitability, intellectual overexcitability, sensual overexcitability, psychomotor overexcitability, imaginational overexcitability

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966 Co-Gasification of Petroleum Waste and Waste Tires: A Numerical and CFD Study

Authors: Thomas Arink, Isam Janajreh

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The petroleum industry generates significant amounts of waste in the form of drill cuttings, contaminated soil and oily sludge. Drill cuttings are a product of the off-shore drilling rigs, containing wet soil and total petroleum hydrocarbons (TPH). Contaminated soil comes from different on-shore sites and also contains TPH. The oily sludge is mainly residue or tank bottom sludge from storage tanks. The two main treatment methods currently used are incineration and thermal desorption (TD). Thermal desorption is a method where the waste material is heated to 450ºC in an anaerobic environment to release volatiles, the condensed volatiles can be used as a liquid fuel. For the thermal desorption unit dry contaminated soil is mixed with moist drill cuttings to generate a suitable mixture. By thermo gravimetric analysis (TGA) of the TD feedstock it was found that less than 50% of the TPH are released, the discharged material is stored in landfill. This study proposes co-gasification of petroleum waste with waste tires as an alternative to thermal desorption. Co-gasification with a high-calorific material is necessary since the petroleum waste consists of more than 60 wt% ash (soil/sand), causing its calorific value to be too low for gasification. Since the gasification process occurs at 900ºC and higher, close to 100% of the TPH can be released, according to the TGA. This work consists of three parts: 1. a mathematical gasification model, 2. a reactive flow CFD model and 3. experimental work on a drop tube reactor. Extensive material characterization was done by means of proximate analysis (TGA), ultimate analysis (CHNOS flash analysis) and calorific value measurements (Bomb calorimeter) for the input parameters of the mathematical and CFD model. The mathematical model is a zero dimensional model based on Gibbs energy minimization together with Lagrange multiplier; it is used to find the product species composition (molar fractions of CO, H2, CH4 etc.) for different tire/petroleum feedstock mixtures and equivalence ratios. The results of the mathematical model act as a reference for the CFD model of the drop-tube reactor. With the CFD model the efficiency and product species composition can be predicted for different mixtures and particle sizes. Finally both models are verified by experiments on a drop tube reactor (1540 mm long, 66 mm inner diameter, 1400 K maximum temperature).

Keywords: computational fluid dynamics (CFD), drop tube reactor, gasification, Gibbs energy minimization, petroleum waste, waste tires

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965 725 Arcadia Street in Pretoria: A Pretoria Case Study Focusing on Urban Acupuncture

Authors: Konrad Steyn, Jacques Laubscher

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South African urban design solutions are mostly aligned with European and North American models that are often not appropriate in addressing some of this country’s challenges such as multiculturalism and decaying urban areas. Sustainable urban redevelopment in South Africa should be comprehensive in nature, sensitive in its manifestation, and should be robust and inclusive in order to achieve social relevance. This paper argues that the success of an urban design intervention is largely dependent on the public’s perceptions and expectations, and the way people participate in shaping their environments. The concept of sustainable urbanism is thus more comprehensive than – yet should undoubtedly include – methods of construction, material usage and climate control principles. The case study is a central element of this research paper. 725 Arcadia Street in Pretoria, was originally commissioned as a food market structure. A starkly contrasting existing modernist adjacent building forms the morphological background. Built in 1969, it is a valuable part of Pretoria’s modernist fabric. It was realised early on that the project should not be a mere localised architectural intervention, but rather an occasion to revitalise the neighbourhood through urban regeneration. Because of the complex and comprehensive nature of the site and rich cultural diversity of the area, a multi-faceted approach seemed the most appropriate response. The methodology for collating data consisted of a combination of literature reviews (regarding the historic original fauna and flora and current plants, observation (frequent site visits) and physical surveying on the neighbourhood level (physical location, connectivity to surrounding landmarks as well as movement systems and pedestrian flows). This was followed by an exploratory design phase, culminating in the present redevelopment proposal. Since built environment interventions are increasingly based on generalised normative guidelines, an approach focusing of urban acupuncture could serve as an alternative. Celebrating the specific urban condition, urban acupuncture offers an opportunity to influence the surrounding urban fabric and achieve urban renewal through physical, social and cultural mediation.

Keywords: neighbourhood, urban renewal, South African urban design solutions, sustainable urban redevelopment

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964 Assessing the Geothermal Parameters by Integrating Geophysical and Geospatial Techniques at Siwa Oasis, Western Desert, Egypt

Authors: Eman Ghoneim, Amr S. Fahil

Abstract:

Many regions in Egypt are facing a reduction in crop productivity due to environmental degradation. One factor of crop deterioration includes the unsustainable drainage of surface water, leading to salinized soil conditions. Egypt has exerted time and effort to identify solutions to mitigate the surface water drawdown problem and its resulting effects by exploring renewable and sustainable sources of energy. Siwa Oasis represents one of the most favorable regions in Egypt for geothermal exploitation since it hosts an evident cluster of superficial thermal springs. Some of these hot springs are characterized by high surface temperatures and bottom hole temperatures (BHT) ranging between 20°C to 40 °C and 21 °C to 121.7°C, respectively. The depth to the Precambrian basement rock is commonly greater than 440 m, ranging from 440 m to 4724.4 m. It is this feature that makes the locality of Siwa Oasis sufficient for industrial processes and geothermal power production. In this study, BHT data from 27 deep oil wells were processed by applying the widely used Horner and Gulf of Mexico correction methods to obtain formation temperatures. BHT, commonly used in geothermal studies, remains the most abundant and readily available data source for subsurface temperature information. Outcomes of the present work indicated a geothermal gradient ranging from 18 to 42 °C/km, a heat flow ranging from 24.7 to 111.3 m.W.k⁻¹, and a thermal conductivity of 1.3–2.65 W.m⁻¹.k⁻¹. Remote sensing thermal infrared, topographic, geologic, and geothermal data were utilized to provide geothermal potential maps for the Siwa Oasis. Important physiographic variables (including surface elevation, lineament density, drainage density), geological and geophysical parameters (including land surface temperature, depth to basement, bottom hole temperature, magnetic, geothermal gradient, heat flow, thermal conductivity, and main rock units) were incorporated into GIS to produce a geothermal potential map (GTP) for the Siwa Oasis region. The model revealed that both the northeastern and southeastern sections of the study region are of high geothermal potential. The present work showed that combining bottom-hole temperature measurements and remote sensing data with the selected geospatial methodologies is a useful tool for geothermal prospecting in geologically and tectonically comparable settings in Egypt and East Africa. This work has implications for identifying sustainable resources needed to support food production and renewable energy resources.

Keywords: BHT, geothermal potential map, geothermal gradient, heat flow, thermal conductivity, satellite imagery, GIS

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963 Investigation on Behaviour of Reinforced Concrete Beam-Column Joints Retrofitted with CFRP

Authors: Ehsan Mohseni

Abstract:

The aim of this thesis is to provide numerical analyses of reinforced concrete beams-column joints with/without CFRP (Carbon Fiber Reinforced Polymer) in order to achieve a better understanding of the behaviour of strengthened beamcolumn joints. A comprehensive literature survey prior to this study revealed that published studies are limited to a handful only; the results are inconclusive and some are even contradictory. Therefore in order to improve on this situation, following that review, a numerical study was designed and performed as presented in this thesis. For the numerical study, dimensions, end supports, and characteristics of the beam and column models were the same as those chosen in an experimental investigation performed previously where ten beamcolumn joint were tested tofailure. Finite element analysis is a useful tool in cases where analytical methods are not capable of solving the problem due to the complexities associated with the problem. The cyclic behaviour of FRP strengthened reinforced concrete beam-columns joints is such a case. Interaction of steel (longitudinal and stirrups), concrete and FRP, yielding of steel bars and stirrups, cracking of concrete, the redistribution of stresses as some elements unload due to crushing or yielding and the confinement of concrete due to the presence of FRP are some of the issues that introduce the complexities into the problem.Numerical solutions, however, can provide further in formation about the behaviour in lieu of the costly experiments or complex closed form solutions. This thesis presents the results of a numerical study on beam-column joints subjected to cyclic loads that are strengthened with CFRP wraps or strrips in a variety of configurations. The analyses are performed by Abaqus finite element program and are calibrated with the experiments. A range of issues in beam-column joints including the cracking load, the ultimate load, lateral load-displacement curves of joints, are investigated.The numerical results for different configurations of strengthening are compared. Finally, the computed numerical results are compared with those obtained from experiments. the cracking load, the ultimate load, lateral load-displacement curves obtained from numerical analysis for all joints were in very good agreement with the corresponding experimental ones.The results obtained from the numerical analysis in most cases implies that this method is conservative and therefore can be used in design applications with confidence.

Keywords: numerical analysis, strengthening, CFRP, reinforced concrete joints

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962 Renewable Energy Storage Capacity Rating: A Forecast of Selected Load and Resource Scenario in Nigeria

Authors: Yakubu Adamu, Baba Alfa, Salahudeen Adamu Gene

Abstract:

As the drive towards clean, renewable and sustainable energy generation is gradually been reshaped by renewable penetration over time, energy storage has thus, become an optimal solution for utilities looking to reduce transmission and capacity cost, therefore the need for capacity resources to be adjusted accordingly such that renewable energy storage may have the opportunity to substitute for retiring conventional energy systems with higher capacity factors. Considering the Nigeria scenario, where Over 80% of the current Nigerian primary energy consumption is met by petroleum, electricity demand is set to more than double by mid-century, relative to 2025 levels. With renewable energy penetration rapidly increasing, in particular biomass, hydro power, solar and wind energy, it is expected to account for the largest share of power output in the coming decades. Despite this rapid growth, the imbalance between load and resources has created a hindrance to the development of energy storage capacity, load and resources, hence forecasting energy storage capacity will therefore play an important role in maintaining the balance between load and resources including supply and demand. Therefore, the degree to which this might occur, its timing and more importantly its sustainability, is the subject matter of the current research. Here, we forecast the future energy storage capacity rating and thus, evaluate the load and resource scenario in Nigeria. In doing so, We used the scenario-based International Energy Agency models, the projected energy demand and supply structure of the country through 2030 are presented and analysed. Overall, this shows that in high renewable (solar) penetration scenarios in Nigeria, energy storage with 4-6h duration can obtain over 86% capacity rating with storage comprising about 24% of peak load capacity. Therefore, the general takeaway from the current study is that most power systems currently used has the potential to support fairly large penetrations of 4-6 hour storage as capacity resources prior to a substantial reduction in capacity ratings. The data presented in this paper is a crucial eye-opener for relevant government agencies towards developing these energy resources in tackling the present energy crisis in Nigeria. However, if the transformation of the Nigeria. power system continues primarily through expansion of renewable generation, then longer duration energy storage will be needed to qualify as capacity resources. Hence, the analytical task from the current survey will help to determine whether and when long-duration storage becomes an integral component of the capacity mix that is expected in Nigeria by 2030.

Keywords: capacity, energy, power system, storage

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