Search results for: combined plough
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2615

Search results for: combined plough

2165 Stress Corrosion Cracking, Parameters Affecting It, Problems Caused by It and Suggested Methods for Treatment: State of the Art

Authors: Adnan Zaid

Abstract:

Stress corrosion cracking (SCC) may be defined as a degradation of the mechanical properties of a material under the combined action of a tensile stress and corrosive environment of the susceptible material. It is a harmful phenomenon which might cause catastrophic fracture without a sign of prior warning. In this paper, the stress corrosion cracking, SCC, process, the parameters affecting it, and the different damages caused by it are given and discussed. Utilization of shot peening as a mean of enhancing the resistance of materials to SCC is given and discussed. Finally, a method for improving materials resistance to SCC by grain refining its structure by some refining elements prior to usage is suggested.

Keywords: stress corrosion cracking, parameters, damages, treatment methods

Procedia PDF Downloads 325
2164 Aging Among Older Immigrant Women

Authors: Michele Charpentier

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This article examines the experiences of aging of older immigrant women. The data are based on qualitative research that was conducted in Quebec/Canada with 83 elderly women from different ethno-cultural backgrounds (Arab, African, Haitian, Japanese, Chinese, Portuguese, Romanian, etc.). The results on how such immigrant women deal with material conditions of existence such as deskilling, aging alone, being more economically independent and the combined effects of liberation from social and family norms associated with age and gender in the light of the migration route, will be presented. For the majority, migration opened up possibilities for personal development and self-affirmation. The findings demonstrated the relevance of the intersectional approach in understanding the complexity and social conditionings of women’s experiences of aging.

Keywords: older immigrant women, qualitative research, experiences of aging, intersectional approach

Procedia PDF Downloads 48
2163 The Performance of Modern Eugenics: Ballroom of the Skies as a Method of Understanding American Social Eugenics

Authors: Michael Stokes

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Using a disability studies approach, this paper analyzes the American science fiction novel Ballroom of the Skies as way to address and access narratives of American exceptionalism in relation to global struggle. Combined with a critical race studies analysis of identity and cultural practice, this essay seeks to find parallels between the treatment of disability and the treatment of the racialized body in literature to forcibly reread potential for multiple assemblages of identity in the speculated futures of science fiction. Thinking through this relationship, the essay constructs a thematic understanding of social eugenics as practiced in American culture.

Keywords: disability studies, science fiction, eugenics, cultural studies

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2162 Investigating the Relationship between Bank and Cloud Provider

Authors: Hatim Elhag

Abstract:

Banking and Financial Service Institutions are possibly the most advanced in terms of technology adoption and use it as a key differentiator. With high levels of business process automation, maturity in the functional portfolio, straight through processing and proven technology outsourcing benefits, Banking sector stand to benefit significantly from Cloud computing capabilities. Additionally, with complex Compliance and Regulatory policies, combined with expansive products and geography coverage, the business impact is even greater. While the benefits are exponential, there are also significant challenges in adopting this model– including Legal, Security, Performance, Reliability, Transformation complexity, Operating control and Governance and most importantly proof for the promised cost benefits. However, new architecture designed should be implemented to align this approach.

Keywords: security, cloud, banking sector, cloud computing

Procedia PDF Downloads 496
2161 Preserving the Cultural Values of the Mararoa River and Waipuna–Freshwater Springs, Southland New Zealand: An Integration of Traditional and Scientific Knowledge

Authors: Erine van Niekerk, Jason Holland

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In Māori culture water is considered to be the foundation of all life and has its own mana (spiritual power) and mauri (life force). Water classification for cultural values therefore includes categories like waitapu (sacred water), waimanawa-whenua (water from under the land), waipuna (freshwater springs), the relationship between water quantity and quality and the relationship between surface and groundwater. Particular rivers and lakes have special significance to iwi and hapu for their rohe (tribal areas). The Mararoa River, including its freshwater springs and wetlands, is an example of such an area. There is currently little information available about the sources, characteristics and behavior of these important water resources and this study on the water quality of the Mararoa River and adjacent freshwater springs will provide valuable information to be used in informed decisions about water management. The regional council of Southland, Environment Southland, is required to make changes under their water quality policy in order to comply with the requirements for the New National Standards for Freshwater to consult with Maori to determine strategies for decision making. This requires an approach that includes traditional knowledge combined with scientific knowledge in the decision-making process. This study provided the scientific data that can be used in future for decision making on fresh water springs combined with traditional values for this particular area. Several parameters have been tested in situ as well as in a laboratory. Parameters such as temperature, salinity, electrical conductivity, Total Dissolved Solids, Total Kjeldahl Nitrogen, Total Phosphorus, Total Suspended Solids, and Escherichia coli among others show that recorded values of all test parameters fall within recommended ANZECC guidelines and Environment Southland standards and do not raise any concerns for the water quality of the springs and the river at the moment. However, the destruction of natural areas, particularly due to changes in farming practices, and the changes to water quality by the introduction of Didymosphenia geminate (Didymo) means Māori have already lost many of their traditional mahinga kai (food sources). There is a major change from land use such as sheep farming to dairying in Southland which puts freshwater resources under pressure. It is, therefore, important to draw on traditional knowledge and spirituality alongside scientific knowledge to protect the waters of the Mararoa River and waipuna. This study hopes to contribute to scientific knowledge to preserve the cultural values of these significant waters.

Keywords: cultural values, freshwater springs, Maori, water quality

Procedia PDF Downloads 278
2160 Rectenna Modeling Based on MoM-GEC Method for RF Energy Harvesting

Authors: Soulayma Smirani, Mourad Aidi, Taoufik Aguili

Abstract:

Energy harvesting has arisen as a prominent research area for low power delivery to RF devices. Rectennas have become a key element in this technology. In this paper, electromagnetic modeling of a rectenna system is presented. In our approach, a hybrid technique was demonstrated to associate both the method of auxiliary sources (MAS) and MoM-GEC (the method of moments combined with the generalized equivalent circuit technique). Auxiliary sources were used in order to substitute specific electronic devices. Therefore, a simple and controllable model is obtained. Also, it can easily be interconnected to form different topologies of rectenna arrays for more energy harvesting. At last, simulation results show the feasibility and simplicity of the proposed rectenna model with high precision and computation efficiency.

Keywords: computational electromagnetics, MoM-GEC method, rectennas, RF energy harvesting

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2159 Electromagnetic Source Direction of Arrival Estimation via Virtual Antenna Array

Authors: Meiling Yang, Shuguo Xie, Yilong Zhu

Abstract:

Nowadays, due to diverse electric products and complex electromagnetic environment, the localization and troubleshooting of the electromagnetic radiation source is urgent and necessary especially on the condition of far field. However, based on the existing DOA positioning method, the system or devices are complex, bulky and expensive. To address this issue, this paper proposes a single antenna radiation source localization method. A single antenna moves to form a virtual antenna array combined with DOA and MUSIC algorithm to position accurately, meanwhile reducing the cost and simplify the equipment. As shown in the results of simulations and experiments, the virtual antenna array DOA estimation modeling is correct and its positioning is credible.

Keywords: virtual antenna array, DOA, localization, far field

Procedia PDF Downloads 365
2158 A Study on ESD Protection Circuit Applying Silicon Controlled Rectifier-Based Stack Technology with High Holding Voltage

Authors: Hee-Guk Chae, Bo-Bae Song, Kyoung-Il Do, Jeong-Yun Seo, Yong-Seo Koo

Abstract:

In this study, an improved Electrostatic Discharge (ESD) protection circuit with low trigger voltage and high holding voltage is proposed. ESD has become a serious problem in the semiconductor process because the semiconductor density has become very high these days. Therefore, much research has been done to prevent ESD. The proposed circuit is a stacked structure of the new unit structure combined by the Zener Triggering (SCR ZTSCR) and the High Holding Voltage SCR (HHVSCR). The simulation results show that the proposed circuit has low trigger voltage and high holding voltage. And the stack technology is applied to adjust the various operating voltage. As the results, the holding voltage is 7.7 V for 2-stack and 10.7 V for 3-stack.

Keywords: ESD, SCR, latch-up, power clamp, holding voltage

Procedia PDF Downloads 542
2157 Determination of the Minimum Time and the Optimal Trajectory of a Moving Robot Using Picard's Method

Authors: Abbes Lounis, Kahina Louadj, Mohamed Aidene

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This paper presents an optimal control problem applied to a robot; the problem is to determine a command which makes it possible to reach a final state from a given initial state in record time. The approach followed to solve this optimization problem with constraints on the control starts by presenting the equations of motion of the dynamic system then by applying Pontryagin's maximum principle (PMP) to determine the optimal control, and Picard's successive approximation method combined with the shooting method to solve the resulting differential system.

Keywords: robotics, Pontryagin's Maximum Principle, PMP, Picard's method, shooting method, non-linear differential systems

Procedia PDF Downloads 252
2156 Ending the Multibillionaire: A Solution to Poverty and Violations of the Right to Health

Authors: Andreanna Kalasountas

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A rampant health crisis is facing America. That health crisis is poverty. Millions of Americans live without knowing when they will eat or where they will sleep. Meanwhile, there are over 600 multi-billionaires in the United States. “In April 2021, U.S. billionaires had nearly twice as much combined wealth than the bottom half of Americans -- $4.56 trillion vs. $2.62 trillion.” It's disturbingly ironic that we live in a country where there are people with more money than they know what to do with (or could spend in a lifetime) while simultaneously, people are losing their life because they do not have enough money to survive. Accordingly, this paper argues for the end of the multi-billionaire; that wealth be capped, captured, and redistributed to the poorest among us. To accomplish this goal, this paper begins by identifying the problem, advocating for a new measurement of poverty; and concludes with a both legal and tax policy solutions and what implementation of those solutions would look like.

Keywords: health and human rights, law and policy, poverty, wealth gap

Procedia PDF Downloads 94
2155 A Brief Review on the Relationship between Pain and Sociology

Authors: Hanieh Sakha, Nader Nader, Haleh Farzin

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Introduction: Throughout history, pain theories have been supposed by biomedicine, especially regarding its diagnosis and treatment aspects. Therefore, the feeling of pain is not only a personal experience and is affected by social background; therefore, it involves extensive systems of signals. The challenges in emotional and sentimental dimensions of pain originate from scientific medicine (i.e., the dominant theory is also referred to as the specificity theory); however, this theory has accepted some alterations by emerging physiology. Then, Von Frey suggested the theory of cutaneous senses (i.e., Muller’s concept: the common sensation of combined four major skin receptors leading to a proper sensation) 50 years after the specificity theory. The pain pathway was composed of spinothalamic tracts and thalamus with an inhibitory effect on the cortex. Pain is referred to as a series of unique experiences with various reasons and qualities. Despite the gate control theory, the biological aspect overcomes the social aspect. Vrancken provided a more extensive definition of pain and found five approaches: Somatico-technical, dualistic body-oriented, behaviorist, phenomenological, and consciousness approaches. The Western model combined physical, emotional, and existential aspects of the human body. On the other hand, Kotarba felt confused about the basic origins of chronic pain. Freund demonstrated and argued with Durkhemian about the sociological approach to emotions. Lynch provided a piece of evidence about the correlation between cardiovascular disease and emotionally life-threatening occurrences. Helman supposed a distinction between private and public pain. Conclusion: The consideration of the emotional aspect of pain could lead to effective, emotional, and social responses to pain. On the contrary, the theory of embodiment is based on the sociological view of health and illness. Social epidemiology shows an imbalanced distribution of health, illness, and disability among various social groups. The social support and socio-cultural level can result in several types of pain. It means the status of athletes might define their pain experiences. Gender is one of the important contributing factors affecting the type of pain (i.e., females are more likely to seek health services for pain relief.) Chronic non-cancer pain (CNCP) has become a serious public health issue affecting more than 70 million people globally. CNCP is a serious public health issue which is caused by the lack of awareness about chronic pain management among the general population.

Keywords: pain, sociology, sociological, body

Procedia PDF Downloads 65
2154 We Wonder If They Mind: An Empirical Inquiry into the Narratological Function of Mind Wandering in Readers of Literary Texts

Authors: Tina Ternes, Florian Kleinau

Abstract:

The study investigates the content and triggers of mind wandering (MW) in readers of fictional texts. It asks whether readers’ MW is productive (text-related) or unproductive (text-unrelated). Methodologically, it bridges the gap between narratological and data-driven approaches by utilizing a sentence-by-sentence self-paced reading paradigm combined with thought probes in the reading of an excerpt of A. L. Kennedy’s “Baby Blue”. Results show that the contents of MW can be linked to text properties. We validated the role of self-reference in MW and found prediction errors to be triggers of MW. Results also indicate that the content of MW often travels along the lines of the text at hand and can thus be viewed as productive and integral to interpretation.

Keywords: narratology, mind wandering, reading fiction, meta cognition

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2153 The Effect of Peer Pressure and Leisure Boredom on Substance Use Among Adolescents in Low-Income Communities in Capetown

Authors: Gaironeesa Hendricks, Shazly Savahl, Maria Florence

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The aim of the study is to determine whether peer pressure and leisure boredom influence substance use among adolescents in low-income communities in Cape Town. Non-probability sampling was used to select 296 adolescents between the ages of 16–18 from schools located in two low-income communities. The measurement tools included the Drug Use Disorders Identification Test, the Resistance to Peer Influence and Leisure Boredom Scales. Multiple regression revealed that the combined influence of peer pressure and leisure boredom predicted substance use, while peer pressure emerged as a stronger predictor than leisure boredom on substance use among adolescents.

Keywords: substance use, peer pressure, leisure boredom, adolescents, multiple regression

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2152 Trends in All-Cause Mortality and Inpatient and Outpatient Visits for Ambulatory Care Sensitive Conditions during the First Year of the COVID-19 Pandemic: A Population-Based Study

Authors: Tetyana Kendzerska, David T. Zhu, Michael Pugliese, Douglas Manuel, Mohsen Sadatsafavi, Marcus Povitz, Therese A. Stukel, Teresa To, Shawn D. Aaron, Sunita Mulpuru, Melanie Chin, Claire E. Kendall, Kednapa Thavorn, Rebecca Robillard, Andrea S. Gershon

Abstract:

The impact of the COVID-19 pandemic on the management of ambulatory care sensitive conditions (ACSCs) remains unknown. To compare observed and expected (projected based on previous years) trends in all-cause mortality and healthcare use for ACSCs in the first year of the pandemic (March 2020 - March 2021). A population-based study using provincial health administrative data.General adult population (Ontario, Canada). Monthly all-cause mortality, and hospitalizations, emergency department (ED) and outpatient visit rates (per 100,000 people at-risk) for seven combined ACSCs (asthma, COPD, angina, congestive heart failure, hypertension, diabetes, and epilepsy) during the first year were compared with similar periods in previous years (2016-2019) by fitting monthly time series auto-regressive integrated moving-average models. Compared to previous years, all-cause mortality rates increased at the beginning of the pandemic (observed rate in March-May 2020 of 79.98 vs. projected of 71.24 [66.35-76.50]) and then returned to expected in June 2020—except among immigrants and people with mental health conditions where they remained elevated. Hospitalization and ED visit rates for ACSCs remained lower than projected throughout the first year: observed hospitalization rate of 37.29 vs. projected of 52.07 (47.84-56.68); observed ED visit rate of 92.55 vs. projected of 134.72 (124.89-145.33). ACSC outpatient visit rates decreased initially (observed rate of 4,299.57 vs. projected of 5,060.23 [4,712.64-5,433.46]) and then returned to expected in June 2020. Reductions in outpatient visits for ACSCs at the beginning of the pandemic combined with reduced hospital admissions may have been associated with temporally increased mortality—disproportionately experienced by immigrants and those with mental health conditions. The Ottawa Hospital Academic Medical Organization

Keywords: COVID-19, chronic disease, all-cause mortality, hospitalizations, emergency department visits, outpatient visits, modelling, population-based study, asthma, COPD, angina, heart failure, hypertension, diabetes, epilepsy

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2151 Radar-Based Classification of Pedestrian and Dog Using High-Resolution Raw Range-Doppler Signatures

Authors: C. Mayr, J. Periya, A. Kariminezhad

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In this paper, we developed a learning framework for the classification of vulnerable road users (VRU) by their range-Doppler signatures. The frequency-modulated continuous-wave (FMCW) radar raw data is first pre-processed to obtain robust object range-Doppler maps per coherent time interval. The complex-valued range-Doppler maps captured from our outdoor measurements are further fed into a convolutional neural network (CNN) to learn the classification. This CNN has gone through a hyperparameter optimization process for improved learning. By learning VRU range-Doppler signatures, the three classes 'pedestrian', 'dog', and 'noise' are classified with an average accuracy of almost 95%. Interestingly, this classification accuracy holds for a combined longitudinal and lateral object trajectories.

Keywords: machine learning, radar, signal processing, autonomous driving

Procedia PDF Downloads 236
2150 Comparison of MODIS-Based Rice Extent Map and Landsat-Based Rice Classification Map in Determining Biomass Energy Potential of Rice Hull in Nueva Ecija, Philippines

Authors: Klathea Sevilla, Marjorie Remolador, Bryan Baltazar, Imee Saladaga, Loureal Camille Inocencio, Ma. Rosario Concepcion Ang

Abstract:

The underutilization of biomass resources in the Philippines, combined with its growing population and the rise in fossil fuel prices confirms demand for alternative energy sources. The goal of this paper is to provide a comparison of MODIS-based and Landsat-based agricultural land cover maps when used in the estimation of rice hull’s available energy potential. Biomass resource assessment was done using mathematical models and remote sensing techniques employed in a GIS platform.

Keywords: biomass, geographic information system (GIS), remote sensing, renewable energy

Procedia PDF Downloads 478
2149 A Feature Clustering-Based Sequential Selection Approach for Color Texture Classification

Authors: Mohamed Alimoussa, Alice Porebski, Nicolas Vandenbroucke, Rachid Oulad Haj Thami, Sana El Fkihi

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Color and texture are highly discriminant visual cues that provide an essential information in many types of images. Color texture representation and classification is therefore one of the most challenging problems in computer vision and image processing applications. Color textures can be represented in different color spaces by using multiple image descriptors which generate a high dimensional set of texture features. In order to reduce the dimensionality of the feature set, feature selection techniques can be used. The goal of feature selection is to find a relevant subset from an original feature space that can improve the accuracy and efficiency of a classification algorithm. Traditionally, feature selection is focused on removing irrelevant features, neglecting the possible redundancy between relevant ones. This is why some feature selection approaches prefer to use feature clustering analysis to aid and guide the search. These techniques can be divided into two categories. i) Feature clustering-based ranking algorithm uses feature clustering as an analysis that comes before feature ranking. Indeed, after dividing the feature set into groups, these approaches perform a feature ranking in order to select the most discriminant feature of each group. ii) Feature clustering-based subset search algorithms can use feature clustering following one of three strategies; as an initial step that comes before the search, binded and combined with the search or as the search alternative and replacement. In this paper, we propose a new feature clustering-based sequential selection approach for the purpose of color texture representation and classification. Our approach is a three step algorithm. First, irrelevant features are removed from the feature set thanks to a class-correlation measure. Then, introducing a new automatic feature clustering algorithm, the feature set is divided into several feature clusters. Finally, a sequential search algorithm, based on a filter model and a separability measure, builds a relevant and non redundant feature subset: at each step, a feature is selected and features of the same cluster are removed and thus not considered thereafter. This allows to significantly speed up the selection process since large number of redundant features are eliminated at each step. The proposed algorithm uses the clustering algorithm binded and combined with the search. Experiments using a combination of two well known texture descriptors, namely Haralick features extracted from Reduced Size Chromatic Co-occurence Matrices (RSCCMs) and features extracted from Local Binary patterns (LBP) image histograms, on five color texture data sets, Outex, NewBarktex, Parquet, Stex and USPtex demonstrate the efficiency of our method compared to seven of the state of the art methods in terms of accuracy and computation time.

Keywords: feature selection, color texture classification, feature clustering, color LBP, chromatic cooccurrence matrix

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2148 Thermal Conductivity of Al2O3/Water-Based Nanofluids: Revisiting the Influences of pH and Surfactant

Authors: Nizar Bouguerra, Ahmed Khabou, Sébastien Poncet, Saïd Elkoun

Abstract:

The present work focuses on the preparation and the stabilization of Al2O3-water based nanofluids. Though they have been widely considered in the past, to the best of our knowledge, there is no clear consensus about a proper way to prepare and stabilize them by the appropriate surfactant. In this paper, a careful experimental investigation is performed to quantify the combined influence of pH and the surfactant on the stability of Al2O3-water based nanofluids. Two volume concentrations of nanoparticles and three nanoparticle sizes have been considered. The good preparation and stability of these nanofluids are evaluated through thermal conductivity measurements. The results show that the optimum value for the thermal conductivity is obtained mainly by controlling the pH of the mixture and surfactants are not necessary to stabilize the solution.

Keywords: nanofluid, thermal conductivity, pH, transient hot wire, surfactant, Al2O3, stability, dispersion, preparation

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2147 Microstructural Interactions of Ag and Sc Alloying Additions during Casting and Artificial Ageing to a T6 Temper in a A356 Aluminium Alloy

Authors: Dimitrios Bakavos, Dimitrios Tsivoulas, Chaowalit Limmaneevichitr

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Aluminium cast alloys, of the Al-Si system, are widely used for shape castings. Their microstructures can be further improved on one hand, by alloying modification and on the other, by optimised artificial ageing. In this project four hypoeutectic Al-alloys, the A356, A356+ Ag, A356+Sc, and A356+Ag+Sc have been studied. The interactions of Ag and Sc during solidification and artificial ageing at 170°C to a T6 temper have been investigated in details. The evolution of the eutectic microstructure is studied by thermal analysis and interrupted solidification. The ageing kinetics of the alloys has been identified by hardness measurements. The precipitate phases, number density, and chemical composition has been analysed by means of transmission electron microscopy (TEM) and EDS analysis. Furthermore, the SHT effect onto the Si eutectic particles for the four alloys has been investigated by means of optical microscopy, image analysis, and the UTS strength has been compared with the UTS of the alloys after casting. The results suggest that the Ag additions, significantly enhance the ageing kinetics of the A356 alloy. The formation of β” precipitates were kinetically accelerated and an increase of 8% and 5% in peak hardness strength has been observed compared to the base A356 and A356-Sc alloy. The EDS analysis demonstrates that Ag is present on the β” precipitate composition. After prolonged ageing 100 hours at 170°C, the A356-Ag exhibits 17% higher hardness strength compared to the other three alloys. During solidification, Sc additions change the macroscopic eutectic growth mode to the propagation of a defined eutectic front from the mold walls opposite to the heat flux direction. In contrast, Ag has no significance effect on the solidification mode revealing a macroscopic eutectic growth similar to A356 base alloy. However, the mechanical strength of the as cast A356-Ag, A356-Sc, and A356+Ag+Sc additions has increased by 5, 30, and 35 MPa, respectively. The outcome is a tribute to the refining of the eutectic Si that takes place which it is strong in the A356-Sc alloy and more profound when silver and scandium has been combined. Moreover after SHT the Al alloy with the highest mechanical strength, is the one with Ag additions, in contrast to the as-cast condition where the Sc and Sc+Ag alloy was the strongest. The increase of strength is mainly attributed to the dissolution of grain boundary precipitates the increase of the solute content into the matrix, the spherodisation, and coarsening of the eutectic Si. Therefore, we could safely conclude for an A356 hypoeutectic alloy additions of: Ag exhibits a refining effect on the Si eutectic which is improved when is combined with Sc. In addition Ag enhance, the ageing kinetics increases the hardness and retains its strength at prolonged artificial ageing in a Al-7Si 0.3Mg hypoeutectic alloy. Finally the addition of Sc is beneficial due to the refinement of the α-Al grain and modification-refinement of the eutectic Si increasing the strength of the as-cast product.

Keywords: ageing, casting, mechanical strength, precipitates

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2146 Pregnancy Outcome in Pregnancy with Low Pregnancy-Associated Plasma Protein A in First Trimester

Authors: Sumi Manjipparambil Surendran, Subrata Majumdar

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Aim: The aim of the study is to find out if low PAPP-A (Pregnancy-Associated Plasma Protein A) levels in the first trimester are associated with adverse obstetric outcome. Methods: A retrospective study was carried out on 114 singleton pregnancies having undergone combined test screening. Results: There is statistically significant increased incidence of low birth weight infants in the low PAPP-A group. However, significant association was not found in the incidence of pre-eclampsia, miscarriage, and placental abruption. Conclusion: Low PAPP-A in the first trimester is associated with fetal growth restriction. Recommendation: Women with low PAPP-A levels in first trimester pregnancy screening require consultant-led care and serial growth scans.

Keywords: pregnancy, pregnancy-associated plasma protein A, PAPP-A, fetal growth restriction, trimester

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2145 Hedging and Corporate Governance: Lessons from the Financial Crisis

Authors: Rodrigo Zeidan

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The paper identifies failures of decision making and corporate governance that allow non-financial companies around the world to develop hedging strategies that lead to hefty losses in the aftermath of the financial crisis. The sample is comprised of 346 companies from 10 international markets, of which 49 companies (and a subsample of 13 distressed companies) lose a combined US$18.9 billion. An event study shows that most companies that present losses in derivatives experience negative abnormal returns, including a number of companies in which the effect is persistent after a year. The results of a probit model indicate that the lack of a formal hedging policy, no monitoring to the CFOs, and considerations of hubris and remuneration contribute to the mismanagement of hedging policies.

Keywords: risk management, hedging, derivatives, monitoring, corporate governance structure, event study, hubris

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2144 Combined Effect of Zinc Supplementation and Ascaridia galli Infection on Oxidative Status in Broiler Chicks

Authors: Veselin Nanev, Margarita Gabrashanska, Neli Tsocheva-Gaytandzieva

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Ascaridiasis in chicks is one of the major causes for the reduction in body weights, higher mortality, and reduction in egg production, worse meat quantity, pathological lesions, blood losses, and secondary infections. It is responsible for economic losses to the poultry. Despite being economically important parasite, little work has been carried out on the role of antioxidants in the pathogenesis of ascaridiasis. Zinc is a trace elements with multiple functions and one of them is its antioxidant ability. The aim of this study was to investigate the combined effect of organic zinc compound (2Gly.ZnCl22H20) and Ascaridia galli infection on the antioxidant status of broiler chicks. The activity of antioxidant enzymes superoxide dismutase, glutathione peroxidase, the level of lipid peroxidation, expressed by malonyl dialdexyde and plasma zinc in chicks experimentally infected with Ascaridia galli was investigated. Parasite burden was studied as well. The study was performed on 80 broiler chicks, Cobb 500 hybrids. They were divided into four groups – 1st group – control (non-treated and non-infected, 2nd group – infected with embryonated eggs of A. galli and without treatment, 3rd group- only treated with 2Gly.ZnCl22H20 compound and gr. 4 - infected and supplemented with Zn-compound. The chicks in gr. 2 and 4 were infected orally with 450 embryonated eggs of A.galli on day 14 post infection. The chicks from gr. 3 and 4 received 40 mg Zn compound /kg of feed after the 1st week of age during 10 days. All chicks were similarly fed, managed and killed at 60 day p.i. Helminthological, biochemical and statistical methods were applied. Reduced plasma Zn content was observed in the infected chicks compared to controls. Zinc supplementation did not restored the lower Zn content. Cu, Zn-SOD was decreased significantly in the infected chicks compared to controls. The GPx – activity was significantly increased in the infected chicks than the controls. Increased GPx activity together with decreased Cu/ZnSOD activity revealed unbalanced antioxidant defense capacity. The increased MDA level in chicks and changes in the activity of the enzymes showed a development of oxidative stress during the infection with A.galli. Zn compound supplementation has been shown to influence the activity of both antioxidant enzymes (SOD, GPx) and reduced MDA in the infected chicks. Organic zinc supplementation improved the antioxidant defense and protect hosts from oxidant destruction, but without any effect on the parasite burden. The number of helminths was similar in both groups. Zn supplementation did not changed the number of parasites. Administration of oral 2Gly.ZnCl22H20 compound has been shown to be useful in chicks infected with A. galli by its improvement of their antioxidant potential.

Keywords: Ascaridia galli, antioxidants, broiler chicks, zinc supplementation

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2143 Impact of UV on Toxicity of Zn²⁺ and ZnO Nanoparticles to Lemna minor

Authors: Gabriela Kalcikova, Gregor Marolt, Anita Jemec Kokalj, Andreja Zgajnar Gotvajn

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Since the 90’s, nanotechnology is one of the fastest growing fields of science. Nanomaterials are increasingly becoming part of many products and technologies. Metal oxide nanoparticles are among the most used nanomaterials. Zinc oxide nanoparticles (nZnO) is widely used due to its versatile properties; it has been used in products including plastics, paints, food, batteries, solar cells and cosmetic products. It is also a very effective photocatalyst used for water treatment. Such expanding application of nZnO increases their possible occurrence in the environment. In the aquatic ecosystem nZnO interact with natural environmental factors such as UV radiation, and thus it is essential to evaluate possible interaction between them. In this context, the aim of our study was to evaluate combined ecotoxicity of nZnO and Zn²⁺ on duckweed Lemna minor in presence or absence UV. Inhibition of vegetative growth of duckweed Lemna minor was monitored over a period of 7 days in multi-well plates. After the experiment, specific growth rate was determined. ZnO nanoparticles used were of primary size 13.6 ± 1.7 nm. The test was conducted with nominal nZnO and Zn²⁺ (in form of ZnCl₂) concentrations of 1, 10, 100 mg/L. Experiment was repeated with presence of natural intensity of UV (8h UV, 10 W/m² UVA, 0.5 W/m² UVB). Concentration of Zn during the test was determined by ICP-MS. In the regular experiment (absence of UV) the specific growth rate was slightly increased by low concentrations of nZnO and Zn²⁺ in comparison to control. However, 10 and 100 mg/L of Zn²⁺ resulted in 45% and 68% inhibition of the specific growth rate, respectively. In case of nZnO both concentrations (10 and 100 mg/L) resulted in similar ~ 30% inhibition and the response was not dose-dependent. The lack of the dose-response relationship is often observed in case of nanoparticles. The possible explanation is that the physical impact prevails instead of chemical ones. In the presence of UV the toxicity of Zn²⁺ was increased and 100 mg/L of Zn²⁺ caused total inhibition of the specific growth rate (100%). On the other hand, 100 mg/L of nZnO resulted in low inhibition (19%) in comparison to the experiment without UV (30%). It is thus expected, that tested nZnO is low photoactive, but could have a good UV absorption and/or reflective properties and thus protect duckweed against UV impacts. Measured concentration of Zn in the test suspension decreased only about 4% after 168h in the case of ZnCl₂. On the other hand concentration of Zn in nZnO test decreased by 80%. It is expected that nZnO were partially dissolved in the medium and at the same time agglomeration and sedimentation of particles took place and thus the concentration of Zn at the water level decreased. Results of our study indicated, that nZnO combined with UV of natural intensity does not increase toxicity of nZnO, but slightly protect the plant against UV negative effects. When Zn²⁺ and ZnO results are compared it seems that dissolved Zn plays a central role in the nZnO toxicity.

Keywords: duckweed, environmental factors, nanoparticles, toxicity

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2142 Sentiment Classification Using Enhanced Contextual Valence Shifters

Authors: Vo Ngoc Phu, Phan Thi Tuoi

Abstract:

We have explored different methods of improving the accuracy of sentiment classification. The sentiment orientation of a document can be positive (+), negative (-), or neutral (0). We combine five dictionaries from [2, 3, 4, 5, 6] into the new one with 21137 entries. The new dictionary has many verbs, adverbs, phrases and idioms, that are not in five ones before. The paper shows that our proposed method based on the combination of Term-Counting method and Enhanced Contextual Valence Shifters method has improved the accuracy of sentiment classification. The combined method has accuracy 68.984% on the testing dataset, and 69.224% on the training dataset. All of these methods are implemented to classify the reviews based on our new dictionary and the Internet Movie data set.

Keywords: sentiment classification, sentiment orientation, valence shifters, contextual, valence shifters, term counting

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2141 Examining the Investment Behavior of Arab Women in the Stock Market

Authors: Razan Salem

Abstract:

Gender plays a vital role in the stock markets because men and women differ in their behavior when investing in stocks. Accordingly, the role of gender differences in investment behavior is an increasingly important strand in the field of behavioral finance research. The investment behaviors of women relative to men have been examined in the behavioral finance literature, mainly for comparison purposes. Women's roles in the stock market have not been examined in the behavioral finance literature, however, particularly with respect to the Arab region. This study aims to contribute towards a better understanding of the investment behavior of Arab women (in regards to their risk tolerance, investment confidence, and investment literacy levels) relative to Arab men; using a sample from Arab women and men investors living in Saudi Arabia and Jordan. In order to achieve the study's main aim, the researcher used non-parametric tests, as Mann-Whitney U test, along with frequency distribution analysis to analyze the study’s primary data. The researcher distributed close-ended online questionnaires to a sample of 550 Arab male and female individuals investing in stocks in both Saudi Arabia and Jordan. The results confirm that the sample Arab women invest less in stocks compared to Arab men due to their risk-averse behaviors and limited confidence levels. The results also reveal that due to Arab women’s very low investment literacy levels, they fear from taking the risk and invest often in stocks relative to Arab men. Overall, the study’s main variables (risk tolerance, investment confidence, and investment literacy levels) have a combined effect on the investment behavior of Arab women and their limited participation in the stock market. Hence, this study is one of the very first studies that indicate the combined effect of the three main variables (which are usually studied separately in the existing literature) on the investment behavior of women, particularly Arab women. This study makes three important contributions to the growing literature on gender differences in investment behavior. First, while the behavioral finance literature documents evidence on gender differences in investment behaviors in many developed countries, there are very limited studies that investigate such differences in Arab countries. Arab women investors, generally, are ignored from the behavioral finance literature due probably to cultural barriers and data collection difficulties. Thus, this study extends the literature to include Arab women and their investment behaviors when trading stock relative to Arab men. Moreover, the study associates women investment literacy and confidence levels with their financial risk behaviors and participation in the stock market. This study provides direct evidence on Arab women's investment behaviors when trading stocks. Overall, studying Arab women investors is important to investigate whether the investment behavior identified for Western women investors are also found in Arab women investors.

Keywords: Arab women, gender differences, investment behavior, stock markets

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2140 Inverse Heat Transfer Analysis of a Melting Furnace Using Levenberg-Marquardt Method

Authors: Mohamed Hafid, Marcel Lacroix

Abstract:

This study presents a simple inverse heat transfer procedure for predicting the wall erosion and the time-varying thickness of the protective bank that covers the inside surface of the refractory brick wall of a melting furnace. The direct problem is solved by using the Finite-Volume model. The melting/solidification process is modeled using the enthalpy method. The inverse procedure rests on the Levenberg-Marquardt method combined with the Broyden method. The effect of the location of the temperature sensors and of the measurement noise on the inverse predictions is investigated. Recommendations are made concerning the location of the temperature sensor.

Keywords: melting furnace, inverse heat transfer, enthalpy method, levenberg–marquardt method

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2139 Combline Cavity Bandpass Filter Design and Implementation Using EM Simulation Tool

Authors: Taha Ahmed Özbey, Sedat Nazlıbilek, Alparslan Çağrı Yapıcı

Abstract:

Combline cavity filters have gained significant attention in recent years due to their exceptional narrowband characteristics, high unloaded Q, remarkable out-of-band rejection, and versatile post-manufacturing tuning capabilities. These filters play a vital role in various wireless communication systems, radar applications, and other advanced technologies where stringent frequency selectivity and superior performance are required. This paper represents combined cavity filter design and implementation by coupling matrix synthesis. Limited filter length, 50 dB out-of-band rejection, and agile design were aimed. To do so, CAD tools and intuitive methods were used.

Keywords: cavity, band pass filter, cavity combline filter, coupling matrix synthesis

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2138 Morphological Rules of Bangla Repetition Words for UNL Based Machine Translation

Authors: Nawab Yousuf Ali, S. Golam, A. Ameer, Ashok Toru Roy

Abstract:

This paper develops new morphological rules suitable for Bangla repetition words to be incorporated into an inter lingua representation called Universal Networking Language (UNL). The proposed rules are to be used to combine verb roots and their inflexions to produce words which are then combined with other similar types of words to generate repetition words. This paper outlines the format of morphological rules for different types of repetition words that come from verb roots based on the framework of UNL provided by the UNL centre of the Universal Networking Digital Language (UNDL) foundation.

Keywords: Universal Networking Language (UNL), universal word (UW), head word (HW), Bangla-UNL Dictionary, morphological rule, enconverter (EnCo)

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2137 An Analytical Method for Bending Rectangular Plates with All Edges Clamped Supported

Authors: Yang Zhong, Heng Liu

Abstract:

The decoupling method and the modified Naiver method are combined for accurate bending analysis of rectangular thick plates with all edges clamped supported. The basic governing equations for Mindlin plates are first decoupled into independent partial differential equations which can be solved separately. Using modified Navier method, the analytic solution of rectangular thick plate with all edges clamped supported is then derived. The solution method used in this paper leave out the complicated derivation for calculating coefficients and obtain the solution to problems directly. Numerical comparisons show the correctness and accuracy of the results at last.

Keywords: Mindlin plates, decoupling method, modified Navier method, bending rectangular plates

Procedia PDF Downloads 596
2136 Modern Methods of Technology and Organization of Production of Construction Works during the Implementation of Construction 3D Printers

Authors: Azizakhanim Maharramli

Abstract:

The gradual transition from entrenched traditional technology and organization of construction production to innovative additive construction technology inevitably meets technological, technical, organizational, labour, and, finally, social difficulties. Therefore, the chosen nodal method will lead to the elimination of the above difficulties, combining some of the usual methods of construction and the myth in world practice that the labour force is subjected to a strong stream of reduction. The nodal method of additive technology will create favourable conditions for the optimal degree of distribution of labour across facilities due to the consistent performance of homogeneous work and the introduction of additive technology and traditional technology into construction production.

Keywords: parallel method, sequential method, stream method, combined method, nodal method

Procedia PDF Downloads 87