Search results for: sub-band common spatial patterns
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 10040

Search results for: sub-band common spatial patterns

5570 Risk Assessment of Heavy Metals in River Sediments and Suspended Matter in Small Tributaries of Abandoned Mercury Mines in Wanshan, Guizhou

Authors: Guo-Hui Lu, Jing-Yi Cai, Ke-Yan Tan, Xiao-Cai Yin, Yu Zheng, Peng-Wei Shao, Yong-Liang Yang

Abstract:

Soil erosion around abandoned mines is one of the important geological agents for pollutant diffuses to the lower reaches of the local river basin system. River loading of pollutants is an important parameter for remediation of abandoned mines. In order to obtain information on pollutant transport and diffusion downstream in mining area, the small tributary system of the Xiaxi River in Wanshan District of Guizhou Province was selected as the research area. Sediment and suspended matter samples were collected and determined for Pb, As, Hg, Zn, Co, Cd, Cu, Ni, Cr, and Mn by inductively coupled plasma mass spectrometry (ICP-MS) and atomic fluorescence spectrometry (AFS) with the pretreatment of wet digestion. Discussions are made for pollution status and spatial distribution characteristics. The total Hg content in the sediments ranged from 0.45 to 16.0 g/g (dry weight) with an average of 5.79 g/g, which was ten times higher than the limit of Class II soil for mercury by the National Soil Environmental Quality Standard. The maximum occurred at the intersection of the Jin River and the Xiaxi River. The potential ecological hazard index (RI) was used to evaluate the ecological risk of heavy metals in the sediments. The average RI value for the whole study area suggests the high potential ecological risk level. High Cd potential ecological risk was found at individual sites.

Keywords: heavy metal, risk assessment, sediment, suspended matter, Wanshan mercury mine, small tributary system

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5569 Analysis of Cardiac Health Using Chaotic Theory

Authors: Chandra Mukherjee

Abstract:

The prevalent knowledge of the biological systems is based on the standard scientific perception of natural equilibrium, determination and predictability. Recently, a rethinking of concepts was presented and a new scientific perspective emerged that involves complexity theory with deterministic chaos theory, nonlinear dynamics and theory of fractals. The unpredictability of the chaotic processes probably would change our understanding of diseases and their management. The mathematical definition of chaos is defined by deterministic behavior with irregular patterns that obey mathematical equations which are critically dependent on initial conditions. The chaos theory is the branch of sciences with an interest in nonlinear dynamics, fractals, bifurcations, periodic oscillations and complexity. Recently, the biomedical interest for this scientific field made these mathematical concepts available to medical researchers and practitioners. Any biological network system is considered to have a nominal state, which is recognized as a homeostatic state. In reality, the different physiological systems are not under normal conditions in a stable state of homeostatic balance, but they are in a dynamically stable state with a chaotic behavior and complexity. Biological systems like heart rhythm and brain electrical activity are dynamical systems that can be classified as chaotic systems with sensitive dependence on initial conditions. In biological systems, the state of a disease is characterized by a loss of the complexity and chaotic behavior, and by the presence of pathological periodicity and regulatory behavior. The failure or the collapse of nonlinear dynamics is an indication of disease rather than a characteristic of health.

Keywords: HRV, HRVI, LF, HF, DII

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5568 The Sensitivity of Electrical Geophysical Methods for Mapping Salt Stores within the Soil Profile

Authors: Fathi Ali Swaid

Abstract:

Soil salinization is one of the most hazardous phenomenons accelerating the land degradation processes. It either occurs naturally or is human-induced. High levels of soil salinity negatively affect crop growth and productivity leading land degradation ultimately. Thus, it is important to monitor and map soil salinity at an early stage to enact effective soil reclamation program that helps lessen or prevent future increase in soil salinity. Geophysical method has outperformed the traditional method for assessing soil salinity offering more informative and professional rapid assessment techniques for monitoring and mapping soil salinity. Soil sampling, EM38 and 2D conductivity imaging have been evaluated for their ability to delineate and map the level of salinity variations at Second Ponds Creek. The three methods have shown that the subsoil in the study area is saline. Salt variations were successfully observed under either method. However, EM38 reading and 2D inversion data show a clear spatial structure comparing to EC1:5 of soil samples in spite of that all soil samples, EM38 and 2D imaging were collected from the same location. Because EM38 readings and 2D imaging data are a weighted average of electrical soil conductance, it is more representative of soil properties than the soil samples method. The mapping of subsurface soil at the study area has been successful and the resistivity imaging has proven to be an advantage. The soil salinity analysis (EC1:5) correspond well to the true resistivity bringing together a good result of soil salinity. Soil salinity clearly indicated by previous investigation EM38 have been confirmed by the interpretation of the true resistivity at study area.

Keywords: 2D conductivity imaging, EM38 readings, soil salinization, true resistivity, urban salinity

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5567 The Effects of Prolonged Social Media Use on Student Health: A Focus on Computer Vision Syndrome, Hand Pain, and Headaches and Mental Status

Authors: Augustine Ndudi Egere, Shehu Adamu, Esther Ishaya Solomon

Abstract:

As internet accessibility and smartphones continue to increase in Nigeria, Africa’s most populous country, social media platforms have become ubiquitous, causing students of 18-25 age brackets to spend more time on social media. The research investigated the impact of prolonged social media use on the physical health of students, with a specific focus on computer vision syndrome, hand pain, headaches and mental status. The study adopted a mixed-methods approach combining quantitative surveys to gather statistical data on usage patterns and symptoms, along with qualitative interviews into the experiences and perceptions of medical practitioners concerning cases under study within the geopolitical region. The result was analyzed using Regression analysis. It was observed that there is a significant correlation between social media usage by the students in the study age bracket concerning computer vision syndrome, hand pain, headache and general mental status. The research concluded by providing valuable insights into potential interventions and strategies to mitigate the adverse effects of excessive social media use on student well-being and recommends, among others, that educational institutions, parents, and students themselves collaborate to implement strategies aimed at promoting responsible and balanced use of social media.

Keywords: social media, student health, computer vision syndrome, hand pain, headaches, mental staus

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5566 Media and Women Empowerment: An Exploration of TV Popular Shows in India

Authors: Mamita Panda

Abstract:

Popular shows are considered to be powerful medium for bringing social change and development. It has the responsibility for not only entertaining, but spreading awareness among common mass which it results social intervention in the major social institutions. Gender construction in one of these social institutions where one can build their capacity to construct a better human society. Mass media in general, TV in particular has an important intervening factor in responding to these processes. The obligatory role of media not only through news but popular shows (serials) becomes compulsion for social formation including construction through gender. This paper attempts to map and examine the gendered contents from serials including viewer’s response to understand the level of influence. The regression analysis shows that socio-economic factors have wider influence on understanding of gender equality including TV popular contents. The social construction of gender through serials remains a serious debatable issue and concern thereafter.

Keywords: construction, empowerment, gender, media and women

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5565 Planktivorous Fish Schooling Responses to Current at Natural and Artificial Reefs

Authors: Matthew Holland, Jason Everett, Martin Cox, Iain Suthers

Abstract:

High spatial-resolution distribution of planktivorous reef fish can reveal behavioural adaptations to optimise the balance between feeding success and predator avoidance. We used a multi-beam echosounder to record bathymetry and the three-dimensional distribution of fish schools associated with natural and artificial reefs. We utilised generalised linear models to assess the distribution, orientation, and aggregation of fish schools relative to the structure, vertical relief, and currents. At artificial reefs, fish schooled more closely to the structure and demonstrated a preference for the windward side, particularly when exposed to strong currents. Similarly, at natural reefs fish demonstrated a preference for windward aspects of bathymetry, particularly when associated with high vertical relief. Our findings suggest that under conditions with stronger current velocity, fish can exercise their preference to remain close to structure for predator avoidance, while still receiving an adequate supply of zooplankton delivered by the current. Similarly, when current velocity is low, fish tend to disperse for better access to zooplankton. As artificial reefs are generally deployed with the goal of creating productivity rather than simply attracting fish from elsewhere, we advise that future artificial reefs be designed as semi-linear arrays perpendicular to the prevailing current, with multiple tall towers. This will facilitate the conversion of dispersed zooplankton into energy for higher trophic levels, enhancing reef productivity and fisheries.

Keywords: artificial reef, current, forage fish, multi-beam, planktivorous fish, reef fish, schooling

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5564 Bullying with Neurodiverse Students and Education Policy Reform

Authors: Fharia Tilat Loba

Abstract:

Studies show that there is a certain group of students who are more vulnerable to bullying due to their physical appearance, disability, sexual preference, race, and lack of social and behavioral skills. Students with autism spectrum disorders (ASD) are one of the most vulnerable groups among these at-risk groups. Researchers suggest that focusing on vulnerable groups of students who can be the target of bullying helps to understand the causes and patterns of aggression, which ultimately helps in structuring intervention programs to reduce bullying. Since Australia ratified the United Nations Convention on the Rights of Persons with Disabilities in 2006, it has been committed to providing an inclusive, safe, and effective learning environment for all children. In addition, the 2005 Disability Standards for Education seeks to ensure that students with disabilities can access and participate in education on the same basis as other students, covering all aspects of education, including harassment and victimization. However, bullying hinders students’ ability to fully participate in schooling. The proposed study aims to synthesize the notions of traditional bullying and cyberbullying and attempts to understand the experiences of students with ASD who are experiencing bullying in their schools. The proposed study will primarily focus on identifying the gaps between policy and practice related to bullying, and it will also attempt to understand the experiences of parents of students with ASD and professionals who have experience dealing with bullying at the school level in Australia. This study is expected to contribute to the theoretical knowledge of the bullying phenomenon and provide a reference for advocacy at the school, organization, and government levels.

Keywords: education policy, bullying, Australia, neurodiversity

Procedia PDF Downloads 42
5563 Modeling Soil Erosion and Sediment Yield in Geba Catchment, Ethiopia

Authors: Gebremedhin Kiros, Amba Shetty, Lakshman Nandagiri

Abstract:

Soil erosion is a major threat to the sustainability of land and water resources in the catchment and there is a need to identify critical areas of erosion so that suitable conservation measures may be adopted. The present study was taken up to understand the temporal and spatial distribution of soil erosion and daily sediment yield in Geba catchment (5137 km2) located in the Northern Highlands of Ethiopia. Soil and Water Assessment Tool (SWAT) was applied to the Geba catchment using data pertaining to rainfall, climate, soils, topography and land use/land cover (LU/LC) for the historical period 2000-2013. LU/LC distribution in the catchment was characterized using LANDSAT satellite imagery and the GIS-based ArcSWAT version of the model. The model was calibrated and validated using sediment concentration measurements made at the catchment outlet. The catchment was divided into 13 sub-basins and based on estimated soil erosion, these were prioritized on the basis of susceptibility to soil erosion. Model results indicated that the average sediment yield estimated of the catchment was 12.23 tons/ha/yr. The generated soil loss map indicated that a large portion of the catchment has high erosion rates resulting in significantly large sediment yield at the outlet. Steep and unstable terrain, the occurrence of highly erodible soils and low vegetation cover appeared to favor high soil erosion. Results obtained from this study prove useful in adopting in targeted soil and water conservation measures and promote sustainable management of natural resources in the Geba and similar catchments in the region.

Keywords: Ethiopia, Geba catchment, MUSLE, sediment yield, SWAT Model

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5562 Morphological, Mechanical, and Tribological Properties Investigations of CMTed Parts of Al-5356 Alloy

Authors: Antar Bouhank, Youcef Beellal, Samir Adjel, Abdelmadjid Ababsa

Abstract:

This paper investigates the impact of 3D printing parameters using the cold metal transfer (CMT) technique on the morphological, mechanical, and tribological properties of walls and massive parts made from aluminum alloy. The parameters studied include current intensity, torch movement speed, printing increment, and the flow rate of shielding gas. The manufactured parts, using the technique mentioned above, are walls and massive parts with different filling strategies, using grid and zigzag patterns and at different current intensities. The main goal of the article is to find out the welding parameters suitable for having parts with low defects and improved properties from the previously mentioned properties point of view. It has been observed from the results thus obtained that the high current intensity causes rapid solidification, resulting in high porosity and low hardness values. However, the high current intensity can cause very rapid solidification, which increases the melting point, and the part remains in the most stable shape. Furthermore, the results show that there is an evident relationship between hardness, coefficient of friction and wear test where the high intensity is, the low hardness is. The same note is for the coefficient of friction. The micrography of the walls shows a random granular structure with fine grain boundaries with a different grain size. Some interesting results are presented in this paper.

Keywords: aluminum alloy, porosity, microstructures, hardness

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5561 Effects of Copper Oxide Doping on Hydrothermal Ageing in Alumina Toughened Zirconia

Authors: Mohamed Abbas, Ramesh Singh

Abstract:

This study investigates the hydrothermal aging behavior of undoped and copper oxide-doped alumina-toughened zirconia (ATZ). The ATZ ceramic composites underwent conventional sintering at temperatures ranging from 1250 to 1500°C with a holding time of 12 minutes. XRD analysis revealed a stable 100% tetragonal phase for conventionally sintered ATZ samples up to 1450°C, even after 100 hours of exposure. At 1500℃, XRD patterns of both undoped and doped ATZ samples showed no phase transformation after up to 3 hours of exposure to superheated steam. Extended exposure, however, resulted in phase transformation beyond 10 hours. CuO-doped ATZ samples initially exhibited lower monoclinic content, gradually increasing with aging. Undoped ATZ demonstrated better-aging resistance, maintaining ~40% monoclinic content after 100 hours. FESEM images post-aging revealed surface roughness changes due to the tetragonal-to-monoclinic phase transformation, with limited nucleation in the largest tetragonal grains. Fracture analysis exhibited macrocracks and microcracks on the transformed surface layer after aging. This study found that 0.2wt% CuO doping did not prevent the low-temperature degradation (LTD) phenomenon at elevated temperatures. Transformation zone depth (TZD) calculations supported the trend observed in the transformed monoclinic phase.

Keywords: alumina toughened zirconia, conventional sintering, copper oxide, hydrothermal ageing

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5560 Efficient Sources and Methods of Extracting Water for Irrigation

Authors: Anthony Iyenjamu, Josiah Adeyemo

Abstract:

Due to the increasing water scarcity in South Africa, the prime focus of irrigation in South Africa shifts to creating feasible water sources and the efficient use of these sources. These irrigation systems in South Africa are implemented because of low and erratic rainfall and high evaporative demand. Irrigation contributes significantly to crop production in South Africa, as the mean annual precipitation for the country is usually less than 500mm. This is considered to be the minimum required for rain fed cropping. Even though the rainfall is low, a lot of the water in various areas in South Africa is lost due to runoff into storm water systems that run to the rivers and eventually into the sea. This study reviews the irrigation systems in South Africa which can be vastly improved by creating irrigation dams. A method of which may seem costly at first but rewarding with time. The study investigates the process of creating dam capacity capable of sustaining a suitable area size of land to be irrigated and thus diverting all runoff into these dams. This type of infrastructure method vastly improves various sectors in our irrigation systems. Extensive research is carried out in the surrounding area in which the dam should be constructed. Rainfall patterns and rainfall data is used for calculations of which period the dam will be at its optimum using rainfall. The size of the area irrigated was used to calculate the size of the irrigation dam to be constructed. The location of the dam must be situated as close to the river as possible to minimize the excessive use of pipelines to the dam. This study also investigated all existing resources to alleviate the cost. It was found that irrigation dams could solve the erratic distribution of rainfall in South Africa for irrigation purposes.

Keywords: irrigation, rainfed, rain harvesting, reservoir

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5559 Epileptic Seizure Prediction Focusing on Relative Change in Consecutive Segments of EEG Signal

Authors: Mohammad Zavid Parvez, Manoranjan Paul

Abstract:

Epilepsy is a common neurological disorders characterized by sudden recurrent seizures. Electroencephalogram (EEG) is widely used to diagnose possible epileptic seizure. Many research works have been devoted to predict epileptic seizure by analyzing EEG signal. Seizure prediction by analyzing EEG signals are challenging task due to variations of brain signals of different patients. In this paper, we propose a new approach for feature extraction based on phase correlation in EEG signals. In phase correlation, we calculate relative change between two consecutive segments of an EEG signal and then combine the changes with neighboring signals to extract features. These features are then used to classify preictal/ictal and interictal EEG signals for seizure prediction. Experiment results show that the proposed method carries good prediction rate with greater consistence for the benchmark data set in different brain locations compared to the existing state-of-the-art methods.

Keywords: EEG, epilepsy, phase correlation, seizure

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5558 Deep Vision: A Robust Dominant Colour Extraction Framework for T-Shirts Based on Semantic Segmentation

Authors: Kishore Kumar R., Kaustav Sengupta, Shalini Sood Sehgal, Poornima Santhanam

Abstract:

Fashion is a human expression that is constantly changing. One of the prime factors that consistently influences fashion is the change in colour preferences. The role of colour in our everyday lives is very significant. It subconsciously explains a lot about one’s mindset and mood. Analyzing the colours by extracting them from the outfit images is a critical study to examine the individual’s/consumer behaviour. Several research works have been carried out on extracting colours from images, but to the best of our knowledge, there were no studies that extract colours to specific apparel and identify colour patterns geographically. This paper proposes a framework for accurately extracting colours from T-shirt images and predicting dominant colours geographically. The proposed method consists of two stages: first, a U-Net deep learning model is adopted to segment the T-shirts from the images. Second, the colours are extracted only from the T-shirt segments. The proposed method employs the iMaterialist (Fashion) 2019 dataset for the semantic segmentation task. The proposed framework also includes a mechanism for gathering data and analyzing India’s general colour preferences. From this research, it was observed that black and grey are the dominant colour in different regions of India. The proposed method can be adapted to study fashion’s evolving colour preferences.

Keywords: colour analysis in t-shirts, convolutional neural network, encoder-decoder, k-means clustering, semantic segmentation, U-Net model

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5557 From Orthodox to Haploid Mitochondrial DNA Markers: Exploring the Datum Folder of population of Sindh in Pakistan

Authors: Shahzad Bhattiab, M. Aslamkhana, Sana Abbasbc, Marcella Attimonellid, Kumarasamy Thangaraje, Erica Martinha Silva de Souzaf, Uzay U. Sezen

Abstract:

The present study was designed to investigate three regions of mitochondrial DNA, HVI, HVII and HVIII, to hold a powwow genetic diversity and affiliations in 115 probands of 6 major ethnic groups, viz., Bijarani, Chandio, Ghallu, Khoso, Nasrani and Solangi, in the province of Sindh of Pakistan. For this purpose 88 haplotypes were scrutinized, defined by particular set of nucleotides (ignoring the C insertions around position 309 and 315). In spite of that 82% sequences were observed once, 12 % twice and 5.2 % thrice. The most common South Asian haplotypes were observed M (42%), N (6.9%) and R (6.9%) whereas west Eurasian haplotypes were J (1.7%), U (23.4%), H (9.5%), W (6.9%) and T (0.86%), in six ethnic groups. A random match probability between two unrelated individuals was found 0.06 %, while genetic diversity was ranged to be 0.991 to 0.999, and nucleotide diversity ranged from 0.0089 to 0.0142 for the whole control region of the population studied.

Keywords: mtDNA haplogroups, control region, Pakistan, Sindh, ethnicity

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5556 Fear of Gender-Based Crime and Women Empowerment: An Empirical Study among the Urban Residents of Bangladesh

Authors: Mohammad Ashraful Alam, Biro Judit

Abstract:

Fear of gender-based crime and fear of crime victimization for women is a major concern in the urban areas of Bangladesh. Based on the recent data from various human rights organizations and international literature the study found that gender-based crime especially sexual assault and rape are increasing in Bangladesh at a significant rate in comparison to other countries. The major focus of the study was to identify the relationship between fear of gender-based crime and women empowerment. To explore the fact the study followed the mixed methodological approach comprising with quantitative and qualitative methods and used secondary information from national and international sources. Corresponding global pictures the present study found that gender, age, complexion, social position, and ethnicity were more common factors of sexual assault and victimization in Bangladesh which lead to women become more fearful about crime victimization than men. Fear of gender-based crime traumatizes women which leads to withdrawal of their non-essential everyday works and some time from the essential works based on their social position, financial status, and social honor in the society. The increasing crime rate also increases the propensity to fear of criminal victimization, traumatization, and feeling of helplessness which make them vulnerable. The patriarchal culture and practices in Bangladesh based on religious culture and established social norms women always feel defenseless therefore they withdraw themselves from various social activities and own interest. Women who have already victimized feel more fear and become traumatized, and who do not victimize yet but know the severity of victimization from the media and others’ have the feeling of fear of crime. Women who find themselves as weak bonding and low networks with their neighbors and living for a short duration have a feeling of more fear and avoid visiting a certain place in a certain time and avoid some social activities. The study found the young women have more possibilities to become victimized through the feeling of fear of crime is higher among elderly women than young. Though women feel fear of all kinds of crime but usually all aged women are more fearful of sexual assault and rape than other violent crimes. Therefore, elderly women and another person in the family does not allow younger girls to go and involve outside activities to secure their family status. On the other hand, fear of crime in public transport is more common to all aged women at a higher level and sometimes they compromise their freedom, independence, financial opportunities, the job only to avoid the perceived threat, and save their social and cultural honor. The study also explores that fear of crime does not always depend on crime rate but the crime news, the severity of the crime, delay justice, the ineffectiveness of police, bail of criminals, corruption and political favoritism, etc. Finally, the study shows that the fear of gender-based crime and violence is working as a potential barrier to ensuring women's empowerment in Bangladesh.

Keywords: compromise personal freedom, fear of crime, fear of gender-based crime, fear of violent crime victimization, rape, sexual assaults, withdrawal from regular activities, women empowerment

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5555 Anomaly Detection in Financial Markets Using Tucker Decomposition

Authors: Salma Krafessi

Abstract:

The financial markets have a multifaceted, intricate environment, and enormous volumes of data are produced every day. To find investment possibilities, possible fraudulent activity, and market oddities, accurate anomaly identification in this data is essential. Conventional methods for detecting anomalies frequently fail to capture the complex organization of financial data. In order to improve the identification of abnormalities in financial time series data, this study presents Tucker Decomposition as a reliable multi-way analysis approach. We start by gathering closing prices for the S&P 500 index across a number of decades. The information is converted to a three-dimensional tensor format, which contains internal characteristics and temporal sequences in a sliding window structure. The tensor is then broken down using Tucker Decomposition into a core tensor and matching factor matrices, allowing latent patterns and relationships in the data to be captured. A possible sign of abnormalities is the reconstruction error from Tucker's Decomposition. We are able to identify large deviations that indicate unusual behavior by setting a statistical threshold. A thorough examination that contrasts the Tucker-based method with traditional anomaly detection approaches validates our methodology. The outcomes demonstrate the superiority of Tucker's Decomposition in identifying intricate and subtle abnormalities that are otherwise missed. This work opens the door for more research into multi-way data analysis approaches across a range of disciplines and emphasizes the value of tensor-based methods in financial analysis.

Keywords: tucker decomposition, financial markets, financial engineering, artificial intelligence, decomposition models

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5554 Microstructural Characterization of Creep Damage Evolution in Welded Inconel 600 Superalloy

Authors: Lourdes Yareth Herrera-Chavez, Alberto Ruiz, Victor H. Lopez

Abstract:

Superalloys are used in components that operate at high temperatures such as pressure vessels and heat exchanger tubing. Design standards for these components must consider creep resistance among other criteria. Fusion welding processes are commonly used in the industry to join such components. Fusion processes commonly generate three distinctive zones, i.e. heat affected zone (HAZ), namely weld metal (WM) and base metal (BM). In nickel-based superalloy, the microstructure developed during fusion welding dictates the mechanical response of the welded component and it is very important to establish these effects in the mechanical response of the component. In this work, two plates of Inconel 600 superalloy were Gas Metal Arc Welded (GMAW). Creep samples were cut and milled to specifications and creep tested at a temperature (650 °C) using stress level of 350, 300, 275, 250 and 200 MPa. Microstructural analysis results showed a progressive creep damage evolution that depends on the stress levels with a preferential accumulation of creep damage at the heat affected zone where the creep rupture preferentially occurs owing to an austenitic matrix with grain boundary precipitated of the type Cr23C6. The fractured surfaces showed dimple patterns of cavity and voids. Results indicated that the damage mechanism is due to cavity growth by the combined effect of the power law and diffusion creep.

Keywords: austenitic microstructure, creep damage evolution, heat affected zone, vickers microhardness

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5553 Electromagnetic Modeling of a MESFET Transistor Using the Moments Method Combined with Generalised Equivalent Circuit Method

Authors: Takoua Soltani, Imen Soltani, Taoufik Aguili

Abstract:

The communications' and radar systems' demands give rise to new developments in the domain of active integrated antennas (AIA) and arrays. The main advantages of AIA arrays are the simplicity of fabrication, low cost of manufacturing, and the combination between free space power and the scanner without a phase shifter. The integrated active antenna modeling is the coupling between the electromagnetic model and the transport model that will be affected in the high frequencies. Global modeling of active circuits is important for simulating EM coupling, interaction between active devices and the EM waves, and the effects of EM radiation on active and passive components. The current review focuses on the modeling of the active element which is a MESFET transistor immersed in a rectangular waveguide. The proposed EM analysis is based on the Method of Moments combined with the Generalised Equivalent Circuit method (MOM-GEC). The Method of Moments which is the most common and powerful software as numerical techniques have been used in resolving the electromagnetic problems. In the class of numerical techniques, MOM is the dominant technique in solving of Maxwell and Transport’s integral equations for an active integrated antenna. In this situation, the equivalent circuit is introduced to the development of an integral method formulation based on the transposition of field problems in a Generalised equivalent circuit that is simpler to treat. The method of Generalised Equivalent Circuit (MGEC) was suggested in order to represent integral equations circuits that describe the unknown electromagnetic boundary conditions. The equivalent circuit presents a true electric image of the studied structures for describing the discontinuity and its environment. The aim of our developed method is to investigate the antenna parameters such as the input impedance and the current density distribution and the electric field distribution. In this work, we propose a global EM modeling of the MESFET AsGa transistor using an integral method. We will begin by describing the modeling structure that allows defining an equivalent EM scheme translating the electromagnetic equations considered. Secondly, the projection of these equations on common-type test functions leads to a linear matrix equation where the unknown variable represents the amplitudes of the current density. Solving this equation resulted in providing the input impedance, the distribution of the current density and the electric field distribution. From electromagnetic calculations, we were able to present the convergence of input impedance for different test function number as a function of the guide mode numbers. This paper presents a pilot study to find the answer to map out the variation of the existing current evaluated by the MOM-GEC. The essential improvement of our method is reducing computing time and memory requirements in order to provide a sufficient global model of the MESFET transistor.

Keywords: active integrated antenna, current density, input impedance, MESFET transistor, MOM-GEC method

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5552 Urban Growth Prediction Using Artificial Neural Networks in Athens, Greece

Authors: Dimitrios Triantakonstantis, Demetris Stathakis

Abstract:

Urban areas have been expanded throughout the globe. Monitoring and modeling urban growth have become a necessity for a sustainable urban planning and decision making. Urban prediction models are important tools for analyzing the causes and consequences of urban land use dynamics. The objective of this research paper is to analyze and model the urban change, which has been occurred from 1990 to 2000 using CORINE land cover maps. The model was developed using drivers of urban changes (such as road distance, slope, etc.) under an Artificial Neural Network modeling approach. Validation was achieved using a prediction map for 2006 which was compared with a real map of Urban Atlas of 2006. The accuracy produced a Kappa index of agreement of 0,639 and a value of Cramer's V of 0,648. These encouraging results indicate the importance of the developed urban growth prediction model which using a set of available common biophysical drivers could serve as a management tool for the assessment of urban change.

Keywords: artificial neural networks, CORINE, urban atlas, urban growth prediction

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5551 The Image Redefinition of Urban Destinations: The Case of Madrid and Barcelona

Authors: Montserrat Crespi Vallbona, Marta Domínguez Pérez

Abstract:

Globalization impacts on cities and especially on their centers, especially on those spaces more visible and coveted. Changes are involved in processes such as touristification, gentrification or studentification, in addition of shop trendiness. The city becomes a good of interchange rather than a communal good for its inhabitants and consequently, its value is monetized. So, these different tendencies are analyzed: on one hand, the presence of tourists, the home rental increase, the explosion of businesses related to tourism; on the other hand; the return of middle classes or gentries to the center in a socio-spatial model that has changed highlighting the centers by their culture and their opportunities as well as by the value of public space and centrality; then, the interest of students (national and international) to be part of these city centers as dynamic groups and emerging classes with a higher purchasing power and better cultural capital than in the past; and finally, the conversion of old stores into modern ones, where vintage trend and the renewal of antiquity is the essence. All these transforming processes impact the European cities and redefine their image. All these trends reinforce the impression and brand of the urban center as an attractive space for investment, keeping such nonsense meaningful. These four tendencies have been spreading correlatively impacting the centers and transforming them involving the displacement of former residents of these spaces and revitalizing the center that is financed and commercialized in parallel. The cases of Madrid and Barcelona as spaces of greater evidence in Spain of these tendencies serve to illustrate these processes and represent the spearhead. Useful recommendations are presented to urban planners to find the conciliation of communal and commercialized spaces.

Keywords: gentrification, shop trendiness, studentification, touristification

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5550 Experimental Study on Flooding Phenomena in a Three-Phase Direct Contact Heat Exchanger for the Utilisation in Solar Pond Applications

Authors: Hameed B. Mahood, Ali Sh. Baqir, Alasdair N. Campbell

Abstract:

Experiments to study the limitation of flooding inception of three-phase direct contact condenser have been carried out in a counter-current small diameter vertical condenser. The total column height was 70 cm and 4 cm diameter. Only 48 cm has been used as an active three-phase direct contact condenser height. Vapour pentane with three different initial temperatures (40, 43.5 and 47.5 °C) and water with a constant temperature (19 °C) have been used as a dispersed phase and a continuous phase respectively. Five different continuous phase mass flow rate and four different dispersed phase mass flow rate have been tested throughout the experiments. Dimensionless correlation based on the previous common flooding correlation is proposed to calculate the up flow flooding inception of the three-phase direct contact condenser.

Keywords: Three-phase heat exchanger, condenser, solar energy, flooding phenomena

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5549 Dynamic Programming Based Algorithm for the Unit Commitment of the Transmission-Constrained Multi-Site Combined Heat and Power System

Authors: A. Rong, P. B. Luh, R. Lahdelma

Abstract:

High penetration of intermittent renewable energy sources (RES) such as solar power and wind power into the energy system has caused temporal and spatial imbalance between electric power supply and demand for some countries and regions. This brings about the critical need for coordinating power production and power exchange for different regions. As compared with the power-only systems, the combined heat and power (CHP) systems can provide additional flexibility of utilizing RES by exploiting the interdependence of power and heat production in the CHP plant. In the CHP system, power production can be influenced by adjusting heat production level and electric power can be used to satisfy heat demand by electric boiler or heat pump in conjunction with heat storage, which is much cheaper than electric storage. This paper addresses multi-site CHP systems without considering RES, which lay foundation for handling penetration of RES. The problem under study is the unit commitment (UC) of the transmission-constrained multi-site CHP systems. We solve the problem by combining linear relaxation of ON/OFF states and sequential dynamic programming (DP) techniques, where relaxed states are used to reduce the dimension of the UC problem and DP for improving the solution quality. Numerical results for daily scheduling with realistic models and data show that DP-based algorithm is from a few to a few hundred times faster than CPLEX (standard commercial optimization software) with good solution accuracy (less than 1% relative gap from the optimal solution on the average).

Keywords: dynamic programming, multi-site combined heat and power system, relaxed states, transmission-constrained generation unit commitment

Procedia PDF Downloads 354
5548 Optimizing Human Diet Problem Using Linear Programming Approach: A Case Study

Authors: P. Priyanka, S. Shruthi, N. Guruprasad

Abstract:

Health is a common theme in most cultures. In fact all communities have their concepts of health, as part of their culture. Health continues to be a neglected entity. Planning of Human diet should be done very careful by selecting the food items or groups of food items also the composition involved. Low price and good taste of foods are regarded as two major factors for optimal human nutrition. Linear programming techniques have been extensively used for human diet formulation for quiet good number of years. Through the process, we mainly apply “The Simplex Method” which is a very useful statistical tool based on the theorem of Elementary Row Operation from Linear Algebra and also incorporate some other necessary rules set by the Simplex Method to help solve the problem. The study done by us is an attempt to develop a programming model for optimal planning and best use of nutrient ingredients.

Keywords: diet formulation, linear programming, nutrient ingredients, optimization, simplex method

Procedia PDF Downloads 545
5547 Assessing Smallholder Farmers’ Perception of Climate Change and Coping Strategies Adopted in the Olifants Catchment of South Africa

Authors: Mary Funke Olabanji, Thando Ndarana, Nerhene Davis, Sylvester Okechukwu Ilo

Abstract:

Scientific evidence indicates that climate change is already being experienced by farmers, and its impacts are felt on agricultural and food systems. Understanding the perceptions of farmers on climate change and how they respond to this change is essential to the development and implementation of appropriate policies for agriculture and food security. This paper aims to contribute to the understanding of farmers’ perceptions of climate change, adopted coping strategies, long-term implications of their adaptation choices, and barriers to their decisions to adapt. Data were randomly collected from 73 respondents in five districts located in the Olifants catchment of South Africa. A combination of descriptive statistics and Chi-Square statistical tests using the Statistical Package for Social Science (SPSS) was used to analyse the data obtained from the survey. Results show that smallholder farmers have an in-depth perception of climate change. The most significant changes perceived by farmers were increased temperature and low rainfall. The results equally revealed that smallholder farmers in the Olifants catchment had adopted several adaptation strategies in response to the perceived climate change. The significant adaptation strategies from the results include changing cropping patterns and planting date, use of improved seed variety, and chemical fertilizers. The study, therefore, concludes that crop diversification and agroforestry were more effective and sustainable in mitigating the impact of climate change.

Keywords: adaptation, climate change, perception, smallholder farmers

Procedia PDF Downloads 161
5546 The End Is Just the Beginning: The Importance of Project Post-Implementation Reviews

Authors: Catalin-Teodor Dogaru, Ana-Maria Dogaru

Abstract:

Success means different things to different people. For us, project managers, it becomes even harder to find a definition. Many factors have to be included in the evaluation. Moreover, literature is not very helpful, lacking consensus and neutrality. Post-implementation reviews (PIR) can be an efficient tool in evaluating how things worked on a certain project. Despite the visible progress, PIR is not a very detailed subject yet and there is not a common understanding in this matter. This may be the reason that some organizations include it in the projects’ lifecycle and some do not. Through this paper, we point out the reasons why all project managers should pay proper attention to this important step and to the elements, which can be assessed, beside the already famous triple constraints: cost, budget, and time. It is essential to take notice that PIR is not a checklist. It brings the edge in eliminating subjectivity and judging projects based on actual proof. Based on our experience, our success indicator model, presented in this paper, contributes to the success of the project! In the same time, it increases trust among customers who will perceive success more objectively.

Keywords: project, post implementation, review, success, indicators

Procedia PDF Downloads 357
5545 Healing Performances: Ethnographic Concepts and Emic Perspectives

Authors: S. Ishak, M. G. Nasuruddin

Abstract:

This paper looks at healing performances as ethnographic expressions of local knowledge and culture embedded within the Malay psyche and gemeinschaft. As society develops and progresses, these healing performances are caught within conflicting trajectories which become compounded by the contestations of tradition, religious concerns, locality and modernity. As exemplifications of the Malay ethos, these performances practice common rituals, cater to the innate needs of the practitioners and serve the targeted, closed, local community. This paper traces the ethnographic methods in documenting these practices as rituals of healing in a post-modern world. It delineates the ethnographic concepts used to analyze these rituals, and to semiotically read the varied binarial oppositions and juxtapositions. The paper concludes by highlighting the reconciliatory processes involved in maintaining these ritual performances as exemplifications of the Malay ethos playing an important role in the re-aligning, re-balancing and healing of the Malay community’s psyche.

Keywords: angina, winds, semangat, spirits, traditional theatres, trance

Procedia PDF Downloads 340
5544 Characterization of Femur Development in Mice: A Computational Approach

Authors: Moncayo Donoso Miguelangel, Guevara Morales Johana, Kalenia Flores Kalenia, Barrera Avellaneda Luis Alejandro, Garzon Alvarado Diego Alexander

Abstract:

In mammals, long bones are formed by ossification of a cartilage mold during early embryonic development, forming structures called secondary ossification centers (SOCs), a primary ossification center (POC) and growth plates. This last structure is responsible for long bone growth. During the femur growth, the morphology of the growth plate and the SOCs may vary during different developmental stages. So far there are no detailed morphological studies of the development process from embryonic to adult stages. In this work, we carried out a morphological characterization of femur development from embryonic period to adulthood in mice. 15, 17 and 19 days old embryos and 1, 7, 14, 35, 46 and 52 days old mice were used. Samples were analyzed by a computational approach, using 3D images obtained by micro-CT imaging. Results obtained in this study showed that femur, its growth plates and SOCs undergo morphological changes during different stages of development, including changes in shape, position and thickness. These variations may be related with a response to mechanical loads imposed for muscle development surrounding the femur and a high activity during early stages necessary to support the high growth rates during first weeks and years of development. This study is important to improve our knowledge about the ossification patterns on every stage of bone development and characterize the morphological changes of important structures in bone growth like SOCs and growth plates.

Keywords: development, femur, growth plate, mice

Procedia PDF Downloads 327
5543 Cognitive Impairment in Chronic Renal Patients on Hemodialysis

Authors: Fabiana Souza Orlandi, Juliana Gomes Duarte, Gabriela Dutra Gesualdo

Abstract:

Chronic renal disease (CKD), accompanied by hemodialysis, causes chronic renal failure in a number of situations that compromises not only physical, personal and environmental aspects, but also psychological, social and family aspects. Objective: To verify the level of cognitive impairment of chronic renal patients on hemodialysis. Methodology: This is a descriptive, cross-sectional study. The present study was performed in a Dialysis Center of a city in the interior of the State of São Paulo. The inclusion criteria were: being 18 years or older; have a medical diagnosis of CKD; being in hemodialysis treatment in this unit; and agree to participate in the research, with the signature of the Informed Consent (TCLE). A total of 115 participants were evaluated through the Participant Characterization Instrument and the Addenbrooke Cognitive Exam - Revised Version (ACE-R), being scored from 0 to 100, stipulating the cut-off note for the complete battery <78 and subdivided into five domains: attention and guidance; memory; fluency; language; (66.9%) and caucasian (54.7%), 53.7 (±14.8) years old. Most of the participants were retired (74.7%), with incomplete elementary schooling (36.5%) and the average time of treatment was 46 months. Most of the participants (61.3%) presented impairment in the area of attention and orientation, 80.4% in the spatial visual domain. Regarding the total ACE-R score, 75.7% of the participants presented scores below the established cut grade. Conclusion: There was a high percentage (75.7%) below the cut-off score established for ACE-R, suggesting that there may be some cognitive impairment among these participants, since the instrument only performs a screening on cognitive health. The results of the study are extremely important so that possible interventions can be traced in order to minimize impairment, thus improving the quality of life of chronic renal patients.

Keywords: cognition, chronic renal insufficiency, adult health, dialysis

Procedia PDF Downloads 350
5542 Early Stage Suicide Ideation Detection Using Supervised Machine Learning and Neural Network Classifier

Authors: Devendra Kr Tayal, Vrinda Gupta, Aastha Bansal, Khushi Singh, Sristi Sharma, Hunny Gaur

Abstract:

In today's world, suicide is a serious problem. In order to save lives, early suicide attempt detection and prevention should be addressed. A good number of at-risk people utilize social media platforms to talk about their issues or find knowledge on related chores. Twitter and Reddit are two of the most common platforms that are used for expressing oneself. Extensive research has already been done in this field. Through supervised classification techniques like Nave Bayes, Bernoulli Nave Bayes, and Multiple Layer Perceptron on a Reddit dataset, we demonstrate the early recognition of suicidal ideation. We also performed comparative analysis on these approaches and used accuracy, recall score, F1 score, and precision score for analysis.

Keywords: machine learning, suicide ideation detection, supervised classification, natural language processing

Procedia PDF Downloads 80
5541 Case Study of the Exercise Habits and Aging Anxiety of Taiwanese Insurance Agents

Authors: W. T. Hsu, H. L. Tsai

Abstract:

The rapid aging of the population is a common trend in the world. However, the progress of modern medical technology has increased the average life expectancy. The global population structure has changed dramatically, and the elderly population has risen rapidly. In the face of rapid population growth, it must be noted issues of the aging population must face up to, which are the physiological, psychological, and social problems associated with aging. This study aims to investigate how insurance agents are actively dealing with an aging society, their own aging anxiety, and their exercise habits. Purposive sampling was the sampling method of this study, a total of 204 respondents were surveyed and 204 valid surveys were returned. The returned valid ratio was 100%. Statistical method included descriptive statistics, t-test, and one-way ANOVA. The results of the study found that the insurance agent’s age, seniority, exercise habits to aging anxiety are significantly different.

Keywords: insurance practitioners, aging anxiety, exercise habits, elderly

Procedia PDF Downloads 290