Search results for: simple multiple-attribute rating technique

Authors: Gulshan Kumar Jawa, Sandeep Mohan Ahuja

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With the increase in industrialization, the presence of heavy metals in wastewater streams has turned into a serious concern for the ecosystem. The metals diffuse through the food chains, causing various health hazards. Conventional methods used to remove these heavy metals from water have some limitations, such as cost, secondary pollution due to sludge formation, recovery of metal, economic viability at low metal concentrations, etc. Many of the biomaterials have been investigated by researchers for the adsorption of heavy metals from water solutions as an alternative technique for the last two decades and have found promising results. In this paper, the batch study on the use of pods of acacia karoo for the adsorption of Cd(II) and Pb(II) from aqueous solutions has been reported. The effect of various parameters on the removal of metal ions, such as pH, contact time, stirring speed, initial metal ion concentration, adsorbent dose, and temperature, have been established to find the optimum parameters through one parameter optimization. Further, kinetic, equilibrium, and thermodynamic studies have been conducted. The pods of acacia karoo have shown great potential for adsorption of Cd(II) and Pb(II) from aqueous solutions and have proven to be a better and more economical alternative for the purpose.

Keywords: adsorption, heavy metals, biomaterials, Cadmium(II), Lead(II), pods of acacia karoo

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Authors: Ziyda Abunada

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In-situ remediation of contaminated land with deep mixing can deliver a multi-technique remedial strategy. A field trail includes permeable reactive barrier (PRB) took place at a severely contaminated site in Yorkshire to the north of the UK through the SMiRT (Soil Mix Remediation Technology) project in May 2011. SMiRT involved the execution of the largest research field trials in the UK to provide field validation. Innovative modified bentonite materials in combination with zeolite and organoclay were used to construct six different walls of a hexagonal PRB. Field monitoring, testing and site cores were collected from the PRB twice: once 2 months after the construction and again in March 2014 (almost 34 months later).This paper presents an overview of the results of the PRB materials’ relative performance with some initial 3-year time-related assessment. Results from the monitoring program and the site cores are presented. Some good correlations are seen together with some clear difference among the materials’ efficiency. These preliminary observations represent a potential for further investigations and highlighted the main lessons learned in a filed scale.

Keywords: in-situ remediation, groundwater, permeable reactive barrier, site cores

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Authors: Dib Djalel, Mordjaoui Mourad

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The current trend towards the exploitation of various renewable energy resources has become indispensable, so it is important to improve the efficiency and reliability of the GPV photovoltaic systems. Maximum Power Point Tracking (MPPT) plays an important role in photovoltaic power systems because it maximize the power output from a PV system for a given set of conditions. This paper presents a new fuzzy logic control based MPPT algorithm for solar panel. The solar panel is modeled and analyzed in Matlab/Simulink. The Solar panel can produce maximum power at a particular operating point called Maximum Power Point(MPP). To produce maximum power and to get maximum efficiency, the entire photovoltaic panel must operate at this particular point. Maximum power point of PV panel keeps on changing with changing environmental conditions such as solar irradiance and cell temperature. Thus, to extract maximum available power from a PV module, MPPT algorithms are implemented and Perturb and Observe (P&O) MPPT and fuzzy logic control FLC, MPPT are developed and compared. Simulation results show the effectiveness of the fuzzy control technique to produce a more stable power.

Keywords: MPPT, photovoltaic panel, fuzzy logic control, modeling, solar power

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Authors: M. Top, H. Telli

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Plaster material has been a preferred material especially in the Middle East geography in terms of economy, easy process and thermal insulation since very old times. However, due to the unstable nature of the material, very little has been reached today. For this reason, both finds and studies about stucco ornamentation are very few. In this study, the excavated plasterwork finds used in the architectural ornamentation in the Hosap Castle (Van/Turkey) were considered worth examining since they are rare examples. The stucco relief finds that were found in the castle is discussed. The finds of engraved artifacts on the plasterworks were not addressed. Only the pieces found in Area II and Area III (harem) and surrounding during the cleaning and excavation work carried out at Hosap Kalesi between 2007-2015, will be discussed. This is a general assessment about the finds. It is unknown where many of the pieces found. For this reason, only general appraisal was able to done. Most of the parts are made of mold technique. The motifs on the fragments are similar to the motifs of Ottoman period tiles. Parallel to the settlement history of the castle, thought that these plaster pieces belong to the 16th-17th centuries.

Keywords: stucco decoration, Eastern Anatolia, Ottoman motifs, ornamentation, plasterwork

Procedia PDF Downloads 114

Authors: I-En Lin, Feng-Jung Yang

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In addition to kidney transplant, renal replacement therapy involves hemodialysis and peritoneal dialysis (PD). PD possesses advantages such as maintaining stable physiological blood status and blood pressure, alleviating anemia, and improving mobility, which make it an ideal method for at-home dialysis treatment. However, potential danger still exists despite the numerous advantages of PD, particularly when patients require dialysis exchange four to five times a day, during which improper operation can easily lead to peritonitis. The process of draining and filling is called an exchange and takes about 30 to 40 minutes. Connecting the transfer set requires sterile technique. Transfer set may require a new cap each time that it disconnects from the bag after an exchange. There are many chances to get infection due to unsafe behavior (ex: hand tremor, poor eyesight and weakness, cap fall-down). The proposed semi-automatic connection mechanism used in the PD can greatly reduce infection chances. This light-weight connection device is portable. The device also does not require using throughout the entire process. It is capable of significantly improving quality of life. Therefore, it is very promising to adopt in home care application.

Keywords: automatic connection, catheter, glomerulonephritis, peritoneal dialysis

Procedia PDF Downloads 238

Authors: Brian Basvi

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A technique for analyzing a security's intrinsic value is called fundamental analysis. It involves looking at relevant financial, economic, and other qualitative and quantitative aspects. Earnings Per Share (EPS), a crucial metric in fundamental analysis, is calculated by dividing a company's net income by the total number of outstanding shares. With more than 70 listed businesses, the Zimbabwe Stock Exchange (ZSE) is the primary stock exchange in Zimbabwe. This study applies the EPS financial ratio and stock valuation techniques to historical stock data from 68 companies listed on the Zimbabwe Stock Exchange. According to a ZSE study, EPS significantly affects share prices that are listed on the market. The study's objective was to assess how fundamental analysis affected the idea of EPS in ZSE stock valuation. It concluded that EPS is an important consideration for investors when they make judgments about their investments. According to the study's findings, fundamental analysis is a useful tool for ZSE investors since it offers insightful information about a company's financial performance and aids in decision-making. Investors can have a better understanding of a company's underlying worth and prospects for future growth by looking into EPS and other basic aspects.

Keywords: fundamental analysis, stock valuation, EPS, share pricing

Procedia PDF Downloads 52

Authors: Cotran Mabeya

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This focuses on an artificially intelligent telemedicine application that aims to enrich the access to health care services, especially for those who live in remote and underserved areas. This app is highly packed with very advanced AI technologies—symptom checkers and virtual consultations—as well as health data integration for very efficient and user-friendly remote health support with main features: AI-based diagnostics, real-time health monitoring through wearables, and an intuitive interface. The Telemedicine Application tries too hard to address some of the healthcare problems, such as limited access in remote areas, high costs, lengthy wait times for certain services, as well as difficulty in getting second opinions. By making it friendlier for consultation remotely, the application removes geographic and financial barriers to accessing affordable and timely medical care. In addition, by having centralized patient records and communication between healthcare providers, it allows continuity of care by making it easier to transition to treatment. It has been confirmed that this multi-design approach incorporated both quantitative and qualitative designs to evaluate the socio-economic impacts of artificial intelligence and telemedicine on patients in Nairobi County. Adults made up the target population, while informers and respondents were categorized into patients, healthcare providers, and specialists in law, IT, and AI. Stratified and simple random sampling techniques were used to ensure diversely inclusive representation to enhance accuracy and triangulation in the data collected. Moreover, the study provides several recommendations, which include regular updating accuracy of AI symptom checkers, improving data security through encryption and multi-factor authentication, as well as real-time health data integration from bodily wearables for personal healthcare

Keywords: artificial intelligence, virtual consultations, user-friendly, remote areas

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Authors: Zhen Cheng, Xinyu Dai, Shujian Huang, Jiajun Chen

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Recently, explanatory natural language inference has attracted much attention for the interpretability of logic relationship prediction, which is also known as explanation generation for Natural Language Inference (NLI). Existing explanation generators based on discriminative Encoder-Decoder architecture have achieved noticeable results. However, we find that these discriminative generators usually generate explanations with correct evidence but incorrect logic semantic. It is due to that logic information is implicitly encoded in the premise-hypothesis pairs and difficult to model. Actually, logic information identically exists between premise-hypothesis pair and explanation. And it is easy to extract logic information that is explicitly contained in the target explanation. Hence we assume that there exists a latent space of logic information while generating explanations. Specifically, we propose a generative model called Variational Explanation Generator (VariationalEG) with a latent variable to model this space. Training with the guide of explicit logic information in target explanations, latent variable in VariationalEG could capture the implicit logic information in premise-hypothesis pairs effectively. Additionally, to tackle the problem of posterior collapse while training VariaztionalEG, we propose a simple yet effective approach called Logic Supervision on the latent variable to force it to encode logic information. Experiments on explanation generation benchmark—explanation-Stanford Natural Language Inference (e-SNLI) demonstrate that the proposed VariationalEG achieves significant improvement compared to previous studies and yields a state-of-the-art result. Furthermore, we perform the analysis of generated explanations to demonstrate the effect of the latent variable.

Keywords: natural language inference, explanation generation, variational auto-encoder, generative model

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Authors: Behzad Ali Khan, M. Zubair Akbar Qureshi

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The article analyzes the Darcy Forchheimer 2D Hybrid ferrofluid. The flow of a Hybrid ferrofluid is made due to an unsteady porous channel. The classical liquid water is treated as a based liquid. The flow in the permeable region is characterized by the Darcy-Forchheimer relation. Heat transfer phenomena are studied during the flow. The transformation of a partial differential set of equations into a strong ordinary differential frame is formed through appropriate variables. The numerical Shooting Method is executed for solving the simplified set of equations. In addition, a numerical analysis (ND-Solve) is utilized for the convergence of the applied technique. The influence of some flow model quantities like Pr (Prandtle number), r (porous medium parameter), F (Darcy-porous medium parameter), Re (Reynolds number), Pe (Peclet number) on velocity and temperature field are scrutinized and studied through sketches. Certain physical factors like f ''(η) (skin friction coefficient) and θ^'(η) (rate of heat transfer) are first derived and then presented through tables.

Keywords: darcy forcheimer, hybrid ferro fluid, porous medium, porous channel

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Authors: Mohammad Alkhatatbeh, Nehad Ayoub, Nizar Mhaidat, Nesreen Saadeh, Lisa Lincz

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CD36 is involved in the development of atherosclerosis by enhancing macrophage endocytosis of oxidized-low density lipoproteins and foam cell formation. Soluble CD36 (sCD36) was found to be elevated in type 2 diabetic patients and was supposed to act as a marker of insulin resistance and atherosclerosis. In young subjects, sCD36 was associated with cardiovascular risk factors including obesity and hypertriglyceridemia. This study was conducted to further investigate the relationship between plasma sCD36 and cardiovascular risk factors among middle-aged patients with metabolic syndrome (MetS) and healthy controls. SCD36 concentrations were determined by enzyme-linked immunosorbent assays (ELISA) for 41 patients with MetS and 36 healthy controls. Data for other variables were obtained from patients' medical records. SCD36 concentrations were relatively low compared to most other studies and were not significantly different between the MetS group and controls (P-value=0.17). SCD36 was also not correlated with age, body mass index, glucose, lipid profile, serum electrolytes and blood counts. SCD36 was not significantly different between subjects with obesity, hyperglycemia, dyslipidemia, hypertension or cardiovascular disease and those without these abnormalities (P-value > 0.05). The inconsistency between results reported in this study and other studies may be unique to the study population or be a result of the lack of a reliable standardized method for determining absolute sCD36 concentrations. However, further investigations are required to assess CD36 tissue expression in the study population and to assess the accuracy of various commercially available sCD36 ELISA kits. Thus, the availability of a standardized simple sCD36 ELISA that could be performed in any basic laboratory would be more favorable to the specialized flow cytometry methods that detect CD36+ microparticles if it was to be used as a biomarker.

Keywords: metabolic syndrome, CD36, cardiovascular risk, obesity, type 2 diabetes mellitus

Procedia PDF Downloads 271

Authors: Khaled M. Alhawiti

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Reading capability is a major segment of language competency. On the other hand, discovering topical writings at a fitting level for outside and second language learners is a test for educators. We address this issue utilizing natural language preparing innovation to survey reading level and streamline content. In the connection of outside and second-language learning, existing measures of reading level are not appropriate to this errand. Related work has demonstrated the profit of utilizing measurable language preparing procedures; we expand these thoughts and incorporate other potential peculiarities to measure intelligibility. In the first piece of this examination, we join characteristics from measurable language models, customary reading level measures and other language preparing apparatuses to deliver a finer technique for recognizing reading level. We examine the execution of human annotators and assess results for our finders concerning human appraisals. A key commitment is that our identifiers are trainable; with preparing and test information from the same space, our finders beat more general reading level instruments (Flesch-Kincaid and Lexile). Trainability will permit execution to be tuned to address the needs of specific gatherings or understudies.

Keywords: natural language processing, trainability, syntactic simplification tools, education

Procedia PDF Downloads 494

Authors: Abdelghani Boucheham, Djoudi Bouhafs, Nabil Khelifati, Baya Palahouane

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The main aim of this study is to investigate the low temperature internal gettering of manganese and chromium transition metals content in p-type multicrystalline silicon grown by Heat Exchanger Method (HEM). The minority carrier lifetime variation, the transition metal elements behavior, the sheet resistivity and the interstitial oxygen concentration after different temperatures annealing under N2 ambient were investigated using quasi-steady state photoconductance technique (QSSPC), secondary ion mass spectroscopy (SIMS), four-probe measurement and Fourier transform infrared spectrometer (FTIR), respectively. The obtained results indicate in the temperature range of 300°C to 700°C that the effective lifetime increases and reaches its maximum values of 28 μs at 500 °C and decreasing to 6 μs at 700 °C. This amelioration is due probably to metallic impurities internal gettering in the extended defects and in the oxygen precipitates as observed on SIMS profiles and the FTIR spectra. From 300 °C to 500 °C the sheet resistivity values rest unchanged at 30 Ohm/sq and rises significantly to reach 45 Ohm/sq for T> 500 °C.

Keywords: mc-Si, low temperature annealing, internal gettering, minority carrier lifetime, interstitial oxygen, resistivity

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Authors: Kamil Jonski

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Last year vividly demonstrated, that populism and political instability can endanger democratic institutions in countries regarded as democratic transition champions (Poland) or cornerstones of liberal order (UK, US). So called ‘illiberal democracy’ is winning hearts and minds of voters, keen to believe that rule of strongman is a viable alternative to perceived decay of western values and institutions. These developments pose a serious threat to the democratic institutions (including rule of law), proven critical for both personal freedom and economic development. Although scholars proposed some structural explanations of the illiberal wave (notably focusing on inequality, stagnant incomes and drawbacks of globalization), they seem to have little predictive value. Indeed, events like Trump’s victory, Brexit or Polish shift towards populist nationalism always came as a surprise. Intriguingly, in the case of US election, simple rules like ‘Bread and Peace model’ gauged prospects of Trump’s victory better than pundits and pollsters. This paper attempts to compile set of indicators, in order to gauge various democracies’ vulnerability to populism, instability and pursuance of ‘illiberal’ projects. Among them, it identifies the gap between consensus assessment of institutional performance (as measured by WGI indicators) and citizens’ subjective assessment (survey based confidence in institutions). Plotting these variables against each other, reveals three clusters of countries – ‘predictable’ (good institutions and high confidence, poor institutions and low confidence), ‘blind’ (poor institutions, high confidence e.g. Uzbekistan or Azerbaijan) and ‘disillusioned’ (good institutions, low confidence e.g. Spain, Chile, Poland and US). It seems that this clustering – carried out separately for various institutions (like legislature, executive and courts) and blended with economic indicators like inequality and living standards (using PCA) – offers reasonably good watchlist of countries, that should ‘expect the unexpected’.

Keywords: illiberal democracy, populism, political instability, political risk measurement

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Authors: Diego Romero, Fabio Rojas, J. Alejandro Urrego

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The sounding rockets are aerospace vehicles that were developed in the mid-20th century, and Colombia has been involved in research that was carried out with the aim of innovating with this technology. The rockets are university research programs with the collaboration of the local government, with a simple strategy, develop and reduce the greatest costs associated with the production of a kind type of technology. In this way, in this document presents the failure analysis of a solid rocket motor, with the real compatibly to reach the thermosphere with a low-cost fuel. This solid rocket motor is the latest development of the Uniandes Aerospace Project (PUA for its Spanish acronym), an undergraduate and postgraduate research group at Universidad de los Andes (Bogotá, Colombia), dedicated to incurring in this type of technology. This motor has been carried out on Candy-type solid fuel, which is a compound of potassium nitrate and sorbitol, and the investigation has allowed the production of solid motors powerful enough to reach space, and which represents a unique technological advance in Latin America and an important development in experimental rocketry.To outline the main points the explosion in a static test is an important to explore and demonstrate the ways to develop technology, methodologies, production and manufacturing, being a solid rocket motor with 30 kN of thrust. In conclusion, this analysis explores different fields such as: design, manufacture, materials, production, first fire and more, with different engineering tools with principal objective find root failure. Following the engineering analysis methodology, was possible to design a new version of motor, with learned lessons new manufacturing specification, therefore, when publishing this project, it is intended to be a reference for future research in this field and benefit the industry.

Keywords: candy propellant, candy rockets, explosion, failure analysis, static test, solid rocket motor

Procedia PDF Downloads 163

Authors: I Gede Puja Astawa, Yoedy Moegiharto, Ahmad Zainudin, Imam Dui Agus Salim, Nur Annisa Anggraeni

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Performance of Orthogonal Frequency Division Multiplexing (OFDM) system can be improved by adding channel coding (error correction code) to detect and correct the errors that occur during data transmission. One can use the convolution code. This paper presents performance of OFDM using Space Time Block Codes (STBC) diversity technique use QAM modulation with code rate 1/2. The evaluation is done by analyzing the value of Bit Error Rate (BER) vs. Energy per Bit to Noise Power Spectral Density Ratio (Eb/No). This scheme is conducted 256 sub-carrier which transmits Rayleigh multipath channel in OFDM system. To achieve a BER of 10-3 is required 30 dB SNR in SISO-OFDM scheme. For 2x2 MIMO-OFDM scheme requires 10 dB to achieve a BER of 10-3. For 4x4 MIMO-OFDM scheme requires 5 dB while adding convolution in a 4x4 MIMO-OFDM can improve performance up to 0 dB to achieve the same BER. This proves the existence of saving power by 3 dB of 4x4 MIMO-OFDM system without coding, power saving 7 dB of 2x2 MIMO-OFDM system without coding and significant power savings from SISO-OFDM system.

Keywords: convolution code, OFDM, MIMO, QAM, BER

Procedia PDF Downloads 394

Authors: Surajit Das Barman, Rakibuzzaman Shah, Apurv Kumar

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Bushfire is known as one of the ascendant factors to create pyrocumulus thundercloud that causes the ignition of new fires by pyrocumulonimbus (pyroCb) lightning strikes and creates major losses of lives and property worldwide. A conceptual model-based risk planning would be beneficial to predict the lightning striking zones on the surface of the earth underneath the pyroCb thundercloud. PyroCb thundercloud can generate both positive cloud-to-ground (+CG) and negative cloud-to-ground (-CG) lightning in which +CG tends to ignite more bushfires and cause massive damage to nature and infrastructure. In this paper, a simple line charge structured thundercloud model is constructed in 2-D coordinates using the method of image charge to predict the probable +CG lightning striking zones on the earth’s surface for two conceptual thundercloud charge configurations: titled dipole and conventional tripole structure with excessive lower positive charge regions that lead to producing +CG lightning. The electric potential and surface charge density along the earth’s surface for both structures via continuously adjusting the position and the charge density of their charge regions is investigated. Simulation results for tilted dipole structure confirm the down-shear extension of the upper positive charge region in the direction of the cloud’s forward flank by 4 to 8 km, resulting in negative surface density, and would expect +CG lightning to strike within 7.8 km to 20 km around the earth periphery in the direction of the cloud’s forward flank. On the other hand, the conceptual tripole charge structure with enhanced lower positive charge region develops negative surface charge density on the earth’s surface in the range |x| < 6.5 km beneath the thundercloud and highly favors producing +CG lightning strikes.

Keywords: pyrocumulonimbus, cloud-to-ground lightning, charge structure, surface charge density, forward flank

Procedia PDF Downloads 116

Authors: Oluwasgun Moses Jolayemi

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Violence has become a fairly often occurrence in sports (within our tertiary institutions), a development that is giving every society in the world sleepless night. School violence is part of youth violence, a broader salient public health problem. This study employing a questionnaire-based survey strategy aimed at investigates psychological factors as predictors of sports violence among Oyo state tertiary institution. A sample of Two hundred athletes and three tertiary institutions were selected through purposive sampling from the Oyo State tertiary institution. The estimated reliability co-efficient of the instrument was found to be 0.89 using cronbach Alpha technique. Data were analyzed at 0.05 level of significance using Statistical Package for the Social Sciences (SPSS) software, version 20.0. Five hypotheses were tested using Pearson Correlation. Result revealed that personality, anxiety, mental health has no significant influence on sports violence; mental stress has a significant influence on sports violence. Based on the findings, it was recommended that sport management should reduce work overload and that they should organized seminars and social activities to help athletes lose up.

Keywords: Ibadan, mental health, personality, psychology, violence

Procedia PDF Downloads 307

Authors: Wafula Simon Peter, Kimuli Nabayego Ibtihal, Nabaggala Kimuli Nashua

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The worldwide use of information and communications technology (ICT) equipment and other electronic equipment is growing and consequently, there is a growing amount of equipment that becomes waste after its time in use. This growth is expected to accelerate since equipment lifetime decreases with time and growing consumption. As a result, e-waste is one of the fastest-growing waste streams globally. The United Nations University (UNU) calculates in its second Global E-waste Monitor 44.7 million metric tonnes (Mt) of e-waste were generated globally in 2016. The study population was 80 respondents, from which a sample of 69 respondents was selected using simple and purposive sampling techniques. This research was carried out to investigate the problem of e-waste and come up with a framework to improve e-waste management. The objective of the study was to develop a framework for improving e-waste management at the College of Engineering, Design, Art and Technology (CEDAT). This was achieved by breaking it down into specific objectives, and these included the establishment of the policy and other Regulatory frameworks being used in e-waste management at CEDAT, the determination of the effectiveness of the e-waste management practices at CEDAT, the establishment of the critical challenges constraining e-waste management at the College, development of a framework for e-waste management. The study reviewed the e-waste regulatory framework used at the college and then collected data which was used to come up with a framework. The study also established that weak policy and regulatory framework, lack of proper infrastructure, improper disposal of e-waste and a general lack of awareness of the e-waste and the magnitude of the problem are the critical challenges of e-waste management. In conclusion, the policy and regulatory framework should be revised, localized and strengthened to contextually address the problem. Awareness campaigns, the development of proper infrastructure and extensive research to establish the volumes and magnitude of the problems will come in handy. The study recommends a framework for the improvement of e-waste.

Keywords: e-waste, treatment, disposal, computers, model, management policy and guidelines

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Authors: H. Ben Salah, A. Gannoun, C. de Peretti, A. Trabelsi

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The Downside Risk (DSR) model for portfolio optimisation allows to overcome the drawbacks of the classical mean-variance model concerning the asymetry of returns and the risk perception of investors. This model optimization deals with a positive definite matrix that is endogenous with respect to portfolio weights. This aspect makes the problem far more difficult to handle. For this purpose, Athayde (2001) developped a new recurcive minimization procedure that ensures the convergence to the solution. However, when a finite number of observations is available, the portfolio frontier presents an appearance which is not very smooth. In order to overcome that, Athayde (2003) proposed a mean kernel estimation of the returns, so as to create a smoother portfolio frontier. This technique provides an effect similar to the case in which we had continuous observations. In this paper, taking advantage on the the robustness of the median, we replace the mean estimator in Athayde's model by a nonparametric median estimator of the returns. Then, we give a new version of the former algorithm (of Athayde (2001, 2003)). We eventually analyse the properties of this improved portfolio frontier and apply this new method on real examples.

Keywords: Downside Risk, Kernel Method, Median, Nonparametric Estimation, Semivariance

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Authors: A. Aboubakr, E. Fehling, S. A. Mourad, M. Omar

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Wind energy is one of the most effective renewable sources especially offshore wind energy although offshore wind technology is more costly to produce. It is well known that offshore wind energy can potentially be very cheap once infrastructure and researches improve. Laterally, the trend is to construct offshore wind energy to generate the electricity form wind. This leads to intensive research in order to improve the infrastructures. Offshore wind energy is the construction of wind farms in bodies of water to generate electricity from wind. The most important part in offshore wind turbine structure is the foundation and its connection with the wind tower. This is the main difference between onshore and offshore structures. Grouted connection between the foundation and the wind tower is the most important part of the building process when constructing wind offshore turbines. Most attention should be paid to the actual grout connection as this transfers the loads safely from tower to foundations and the soil also. In this paper, finite element analyses have been carried out for studying the behaviour of offshore grouted connection for wind turbine structures. ATENA program have been used for non-linear analysis simulation of the real structural behavior thus demonstrating the crushing, cracking, contact between the two materials and steel yielding. A calibration of the material used in the simulation has been carried out assuring an accurate model of the used material by ATENA program. This calibration was performed by comparing the results from the ATENA program with experimental results to validate the material properties used in ATENA program. Three simple patch test models with different properties have been performed. The research is concluded with a result that the calibration showing a good agreement between the ATENA program material behaviors and the experimental results.

Keywords: grouted connection, 3D modeling, finite element analysis, offshore wind energy turbines, stresses

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Authors: Joe Amalraj, M. Arunkumar

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Haze is an atmospheric phenomenon that signicantly degrades the visibility of outdoor scenes. This is mainly due to the atmosphere particles that absorb and scatter the light. This paper introduces a novel single image approach that enhances the visibility of such degraded images. In this method is a fusion-based strategy that derives from two original hazy image inputs by applying a white balance and a contrast enhancing procedure. To blend effectively the information of the derived inputs to preserve the regions with good visibility, we filter their important features by computing three measures (weight maps): luminance, chromaticity, and saliency. To minimize artifacts introduced by the weight maps, our approach is designed in a multiscale fashion, using a Laplacian pyramid representation. This paper demonstrates the utility and effectiveness of a fusion-based technique for de-hazing based on a single degraded image. The method performs in a per-pixel fashion, which is straightforward to implement. The experimental results demonstrate that the method yields results comparative to and even better than the more complex state-of-the-art techniques, having the advantage of being appropriate for real-time applications.

Keywords: single image de-hazing, outdoor images, enhancing, DSP

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Authors: Edreese H. Alsharaeh, Feven Mattews Michael, Ayman Almohsin

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Self-healing hydrogels have many advantages since they can resist various types of stresses, including tension, compression, and shear, making them attractive for various applications. In this study, thermo-elastic and self-healing polymer composite hydrogels were prepared from polyacrylamide (PAM) and 2D fillers using in-situ method. In addition, the PAM and fillers were prepared in presence of organic crosslinkers, i.e., hydroquinone (HQ) and hexamethylenediamine (HMT). The swelling behavior of the prepared hydrogels was studied by hydrating the dried hydrogels. The thermal and rheological properties of the prepared hydrogels were evaluated before and after swelling study using thermogravimetric analysis, differential scanning calorimetric technique and dynamic mechanical analysis. From the results obtained, incorporating fillers into the PAM matrix enhanced the swelling degree of the hydrogels with satisfactory mechanical properties, attaining up to 77% self-healing efficiency compared to the neat-PAM (i.e., 29%). This, in turn, indicates addition of 2D fillers improved self-healing properties of the polymer hydrogel, thus, making the prepared hydrogels applicable for water shutoff treatments under high temperature.

Keywords: polymer hydrogels, 2D fillers, elastic self-healing hydrogels, water shutoff, swelling properties

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Authors: Mukisa Simon Peter Turker, Etomaru Irene

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This study examined factors determining the success of University-Industry Collaboration (UIC) in the science academic units (SAUs) at Makerere University. This was prompted by concerns about weak linkages between industry and the academic units at Makerere University. The study examined institutional, relational, output, and framework factors determining the success of UIC in the science academic units at Makerere University. The study adopted a predictive cross-sectional survey design. Data was collected using a questionnaire survey from 172 academic staff from the six SAUs at Makerere University. Stratified, proportionate, and simple random sampling techniques were used to select the samples. The study used descriptive statistics and linear multiple regression analysis to analyze data. The study findings reveal a coefficient of determination (R-square) of 0.403 at a significance level of 0.000, suggesting that UIC success was 40.3% at a standardized error of estimate of 0.60188. The strength of association between Institutional factors, Relational factors, Output factors, and Framework factors, taking into consideration all interactions among the study variables, was at 64% (R= 0.635). Institutional, Relational, Output and Framework factors accounted for 34% of the variance in the level of UIC success (adjusted R2 = 0.338). The remaining variance of 66% is explained by factors other than Institutional, Relational, Output, and Framework factors. The standardized coefficient statistics revealed that Relational factors (β = 0.454, t = 5.247, p = 0.000) and Framework factors (β = 0.311, t = 3.770, p = 0.000) are the only statistically significant determinants of the success of UIC in the SAU in Makerere University. Output factors (β = 0.082, t =1.096, p = 0.275) and Institutional factors β = 0.023, t = 0.292, p = 0.771) turned out to be statistically insignificant determinants of the success of UIC in the science academic units at Makerere University. The study concludes that Relational Factors and Framework Factors positively and significantly determine the success of UIC, but output factors and institutional factors are not statistically significant determinants of UIC in the SAUs at Makerere University. The study recommends strategies to consolidate Relational and Framework Factors to enhance UIC at Makerere University and further research on the effects of Institutional and Output factors on the success of UIC in universities.

Keywords: university-industry collaboration, output factors, relational factors, framework factors, institutional factors

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Authors: Alongkorn Pekalee, Rossarin Gray

Abstract:

Various determinants associated with older health include socio-demographic factors and health-promoting behaviors but lack in scholars recommended what factors associated with health status in specific sub-groups of older adults. The current study aims to explore the health-promoting behaviors and to examine and compare the associations of these factors with self-rated health status among three older age cohorts in Thai traditional context. Methods: This study is based on the Survey of Older Persons in Thailand (SOPT), in 2017, conducted by the National Statistical Office (NSO) of Thailand. Participants were classified into three groups by using the Thai contextual recommendation: youngest-old cohort (60-69), old-old cohort (70-79) and oldest old cohort (80 or older). Health promoting behaviors are the behaviors which associated with the health status of older adults include alcohol consumption, smoking, diet, and physical activity. Health status was defined as a subjective measurement by using self-rated health, a simple measure of general health. The socio-demographic factors, health-promoting behaviors, and health status were explained and summarized by descriptive statistics. The binary logistic regression was performed to analyze the data and evaluate the associations between independent and dependent variables. Results: Increase of age contributes to a higher proportion of health-promoting behaviors. All variables were associated with self-reported health status as good health among three older age cohorts statistically significant (p-value = 0.000). However, the influence of income sufficiency on health status is more notable, especially in older adults who aged 60-69 and 70-79. The influence of dietary and physical activity on health status became greater as age increased. Conclusion: the results suggest that income sufficiency should be noted in a plan to promote healthy aging, and co-residence should be more concerned especially in the oldest old cohort. Moreover, the interventions or policies to promote older health behaviors like diet and physical activity should be emphasized in the oldest old cohort more than others.

Keywords: health-promoting behaviors, older adults, self- rated health, Thailand

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Authors: Mona M. Marzouk, Ahmed Elkhateeb, Mona Elshabrawy, Mai M. Farid, Salwa A. Kawashty, EL-Sayed S. Abdel-Hameed, Sameh R. Hussein

Abstract:

The genus Farsetia Turra belongs to the family Brassicaceae and has approximately 30 accepted species distributed worldwide. Amongst them, Farsetia aegyptia Turra and Farsetia longisiliqua Decne. are two common species characteristic to the Egyptian flora. The present study considers the first characterization of the chemical constituents of F. longisiliqua, aiming to compare with those identified from the medicinal species (F. aegyptia). Additionally, the chemosystematic relationships between the two studied species were evaluated and highlight the medicinal importance for F. longisiliqua. The chemical profiling of their aqueous methanol extracts were carried out using the LC-ESI-MS technique and afforded 54 compounds belonging to different chemical groups. Flavonoids are the major constituents and are represented by 32 compounds (two C-glycosyl flavone, four flavones, and 26 flavonols). Their structural variations and common constituents confirmed the chemosystematic significance of the two species. Moreover, the flavonoid profiles showed major common constituents between the two investigated species, which predicted the medicinal importance of F. longisiliqua.

Keywords: brassicaceae, chemosystematics, farsetia, flavonoids, glucosinolates, LC-ESI-MS

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Authors: Jong Han Joo, Jung Hoon Lee, Young Sun Kim, Jae Young Kang, Seung Ho Choi

Abstract:

In this study, we propose a novel technique for acoustic echo suppression (AES) during speech recognition under barge-in conditions. Conventional AES methods based on spectral subtraction apply fixed weights to the estimated echo path transfer function (EPTF) at the current signal segment and to the EPTF estimated until the previous time interval. We propose a new approach that adaptively updates weight parameters in response to abrupt changes in the acoustic environment due to background noises or double-talk. Furthermore, we devised a voice activity detector and an initial time-delay estimator for barge-in speech recognition in communication networks. The initial time delay is estimated using log-spectral distance measure, as well as cross-correlation coefficients. The experimental results show that the developed techniques can be successfully applied in barge-in speech recognition systems.

Keywords: acoustic echo suppression, barge-in, speech recognition, echo path transfer function, initial delay estimator, voice activity detector

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Authors: Nisha Deopa, Allam Srinivasa Rao

Abstract:

Quaternary potassium lead alumino borate (KPbAlB) glasses doped with different concentration of Eu³⁺ ions have been synthesized by melt quench technique and characterized by X-ray diffraction (XRD), Scanning electron microscope (SEM), Photoluminescence (PL), Time-resolved photoluminescence (TRPL) and CIE-chromaticity co-ordinates to study their luminescence behavior. A broad hump was observed in XRD spectrum confirms glassy nature of as-prepared glasses. By using Judd-Ofelt (J-O) theory, various radiative parameters for the prominent fluorescent levels of Eu³⁺ have been investigated. The intense emission peak was observed at 613 nm (⁵D₀→⁷F₂) under 393 nm excitation, matches well with the excitation of n-UV LED chips. The decay profiles observed for ⁵D₀ level were exponential for lower Eu³⁺ ion concentration while non-exponential for higher concentration, which may be due to efficient energy transfer between Eu³⁺-Eu³⁺ through cross relaxation and subsequent quenching observed. From the emission cross-sections, branching ratios, quantum efficiency and CIE coordinates, it was concluded that 7 mol % of Eu³⁺ ion concentration (glass B) is optimum in KPbAlB glasses for photonic device application.

Keywords: energy transfer, glasses, J-O parameters, photoluminescence

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Authors: Aklilu Alemu, Tak Cheung Chan

Abstract:

Following the intensification of secondary education in the developing world, the attention of Ethiopia has currently shifted to its quality education and its management. This study is aimed to explore experts’ perceptions of quality management challenges in secondary education in Ethiopia. The researchers employed a case study design recruiting participating supervisors from the Ministry of Education, region, zone, wereda, and cluster by using a purposeful sampling technique. Twenty-six interviewees took part in this study. The researchers employed NVivo 8 versions together with a thematic analysis process to analyze the data. This study revealed that major problems that affected quality management practices in Ethiopia were: lack of qualified experts at all levels; lack of accountability in every echelon; the changing nature of teacher education; the ineffectiveness of teacher-licensing programs; and lack of educational budget and the problem of utilizing this limited budget. The study concluded that the experts at different levels were not genuinely fulfilling their roles and responsibilities. Therefore, the Ministry of Finance and Economic Development, together with the concerned parties, needs to reconsider budget allocation for secondary education.

Keywords: education quality, Ethiopia, quality challenge, quality management, secondary education

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Authors: Kelvin Datonye Bob-Manuel

Abstract:

The shipping industry has begun to seriously look at ways of reducing fossil fuel consumption so that current reserves can last longer and operate their ships in a more environmentally friendly way. The concept of Green Shipping or Sustainable Shipping with the use of alternative fuels is now becoming an important issue for ship owners, shipping lines and ship builders globally. This paper provides a critical review of the performance of biodiesel and natural gas-fuelled diesel engines for shipboard application. The emission reduction technique included the use of either neat or emulsified rapeseed methyl ester (RME) for pilot ignition and the emission of NOx, CO2 and SOx were measured at engine speed range of 500 - 1500 r/min. The NOx concentrations were compared with the regulated IMO MARPOL73/78, Annex VI, Tiers I, II, III and United States Environmental Protection Agency (US-EPA) standard. All NOx emissions met Tier I and II levels and the EPA standard for the minimum specification of category 1 engines at higher speed but none met the MARPOL Tier III limit which is for designated Emission Control Areas (ECAs). No trace of soot and SOx emission were observed.

Keywords: dual-fuel, biodiesel, natural gas, NOx, SOx, MARPOL 73/78 Annex VI. USEPA Tier 3, EURO V &VI

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Authors: Archna Mall, Neelam Agrawal, Hari O. Saxena, Bhavana Sharma

Abstract:

Butea monosperma occurs widely throughout central Indian states. Eco-friendly natural dyes were isolated in aqueous medium from leaves, bark and flowers of this plant. These dyes were used for dyeing on cotton fabric using various chemical (potassium aluminium sulphate, potassium dichromate, ferrous sulphate, stannous chloride & tannic acid) and natural mordants (rinds of Terminallia bellerica & Terminalia chebula fruits and shells of Prunus dulcis & Juglans regia nuts). Dyeing was carried out using the pre-mordanting technique. Large range of beautiful shades in terms of hue and darkness were recorded because of varying mordant concentrations and combinations. More importantly dyed fabrics registered varying the degree of colour fastness properties to washing (1-3, colour change and 4-5, colour staining), light (2-4), rubbing (4-5, dry and 3-5, wet) and perspiration (1-4, colour change and 4-5, colour staining). Thus, along with flowers which are traditionally known for natural dyes, the leaves and bark may also find their place in textile industries.

Keywords: Butea monosperma, cotton, mordants, natural dyes

Procedia PDF Downloads 345