Search results for: minimum variance portfolio
2026 Mechanism of Action of Troxerutin in Reducing Oxidative Stress
Authors: Nasrin Hosseinzad
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Troxerutin, a trihydroxyethylated derived of rutin, is a flavonoid existing in tea, coffee, cereal grains, various fruits and vegetables have been conveyed to display radioprotective, antithrombotic, nephron-protective and hepato-protective possessions. Troxerutin, has been well-proved to utilize hepatoprotective assets. Troxerutin could upturn the resistance of hippocampal neurons alongside apoptosis by lessening the action of AChE and oxidative stress. Consequently, troxerutin may have advantageous properties in the administration of Alzheimer's disease and cancer. Troxerutin has been testified to have several welfares and medicinal stuffs. It could shelter the mouse kidney against d-gal-induced damage by refining renal utility, decreasing histopathologic changes, dropping ROS construction, reintroducing the activities of antioxidant enzymes and reducing DNA oxidative destruction. The DNA cleavage study clarifies that troxerutin showed DNA protection against hydroxyl radical persuaded DNA mutilation. Troxerutin uses anti-cancer effect in HuH-7 hepatocarcinoma cells conceivably through synchronized regulation of the molecular signalling pathways, Nrf2 and NF-κB. DNA binding at slight channel by troxerutin may have donated to feature breaks leading to improved radiation brought cell death. Furthermore, the mechanism principal the observed variance in the antioxidant activities of troxerutin and its esters was qualified to equally their free radical scavenging capabilities and dissemination on the cell membrane outward.Keywords: troxerutin, DNA, oxidative stress, antioxidant, free radical
Procedia PDF Downloads 1602025 Finite Element Modeling of Stockbridge Damper and Vibration Analysis: Equivalent Cable Stiffness
Authors: Nitish Kumar Vaja, Oumar Barry, Brian DeJong
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Aeolian vibrations are the major cause for the failure of conductor cables. Using a Stockbridge damper reduces these vibrations and increases the life span of the conductor cable. Designing an efficient Stockbridge damper that suits the conductor cable requires a robust mathematical model with minimum assumptions. However it is not easy to analytically model the complex geometry of the messenger. Therefore an equivalent stiffness must be determined so that it can be used in the analytical model. This paper examines the bending stiffness of the cable and discusses the effect of this stiffness on the natural frequencies. The obtained equivalent stiffness compensates for the assumption of modeling the messenger as a rod. The results from the free vibration analysis of the analytical model with the equivalent stiffness is validated using the full scale finite element model of the Stockbridge damper.Keywords: equivalent stiffness, finite element model, free vibration response, Stockbridge damper
Procedia PDF Downloads 2862024 Molecular Profiling and Potential Bioactive Characteristics of Endophytic Fungi Isolated from Leptadenia Pyrotechnica
Authors: Walaa Al-Maghraby
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Endophytes are organisms that colonize internal plant tissues without causing apparent harm to their host. Almost all groups of microorganisms have been found in endophytic association with plants may be fungi. They stimulate the production of secondary metabolites with a diverse range of biological activities. Leptadenia pyrotechnica is a more or less leafless, erect shrub with straight stems which is highly distributed in Saudi Arabia. Four endophytes fungi were isolated from Leptadenia pyrotechnica and identified using 18S ribosomal RNA sequences, which revealed four fungi genuses, namely Aspergillus terreus; Aspergillus welwitschiae; Aspergillus fumigatus and Aspergillus flavus. In this present study, four endophytic fungi from Leptadenia pyrotechnica were used for obtaining crude aqueous and ethyl acetate extracts for antimicrobial screening against 6 human pathogens, the antibacterial tests presented satisfactory results, where the pathogenic bacteria were inhibited by the four extracts tested, except for Escherichia coli that was inhibited by all extracts except ethyl acetate extract of Aspergillus terreus. Analysis of variance showed that the extract produced by endophyte Leptadenia pyrotechnica was the most effective against all bacteria, either gram-negative or positive. However, the extract was not efficient against pathogenic fungi. Therefore, this study indicates that endophytes from medicinal plant Leptadenia pyrotechnica could be potential sources of antibacterial substances.Keywords: antimicrobial activity, Aspergillus sp, endophytes, Leptadenia pyrotechnica
Procedia PDF Downloads 1402023 Economic Indicators as Correlates of Inward Foreign Direct Investment in Nigeria
Authors: C. F. Popoola, P. Osho, S. B. Babarinde
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This study examined economic indicators as correlates of inward FDI. An exploratory research design was used to obtained annual published data on inflation rate, market size, exchange rate, political instability, human development, and infrastructure from Central Bank of Nigeria, National Bureau of Statistics, Nigerian Capital Market, Nigeria Institute of Social and Economic Research, and UNCTAD. Data generated were analyzed using Pearson correlation, analysis of variance and regression. The findings of the study revealed that market size (r = 0.852, p < 0.001), infrastructure (r = 0.264, p < 0.001), human development (r = 0.154, p < 0.01) and exchange rate ( r= 0.178, p < 0.05) correlate positively with inward FDI, while inflation rate (r = -0.88, p < 0.001), and political instability (r= -0.102, p < 0.05) correlate negatively with inward FDI. Findings also revealed that the economic indicators significantly predicted inward FDI (R2 = 0.913; F(1,19) = 29.40; p < 0.05) for Nigeria. It was concluded that exchange rate, market size, human development, and infrastructure positively related to inward FDI while the high level of inflation and political instability negatively related to inward FDI. Therefore, it was suggested that policy makers and government agencies should readdress steps and design policies that would encourage more FDI into the country.Keywords: exchange rate, foreign direct investment, human development, inflation rate, infrastructure, market size, political instability
Procedia PDF Downloads 4152022 Antimicrobial Activity of Biosynthesized Silver Nanoparticles with Handroanthus Chrysanthus Flower Extract
Authors: Eduardo Padilla, Luis Daniel Rodriguez, Ivan Sanchez, Angelica Sofia Go
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The synthesis and application of metallic nanoparticles have increased in recent years. Biological methods go beyond the chemical and physical synthesis that is expensive and not friendly to the environment. Therefore, in this study, silver nanoparticles were synthesized biologically in an environmentally friendly way by Handroanthus chrysanthus flower aqueous extract (AgNPs) that contains phytochemicals capable of reducing silver nitrate. AgNPs were characterized visually by UV-visible spectroscopy and TEM. The antimicrobial activity of the AgNPs was tested by determining the minimum inhibitory concentration (MIC), and minimal bactericidal concentration (MBC) in Escherichia coli and Staphylococcus aureus strains AgNPs showed potent antimicrobial activity against gram-negative and gram-positive bacteria. MIC and MBC values were as low as 41.6, and 83.2 ug/mL using AgNPs biosynthesized by H. chrysanthus flower extract. This nanoparticle could be the basis for the formulation of disinfectants for use in the food and pharmaceutical industry.Keywords: antimicrobial, silver nanoparticles, flower extract, Handroanthus
Procedia PDF Downloads 1122021 Very First Synthesis of Carbazole Conjugates with Efflux Pump Inhibitor as Dual Action Hybrids
Authors: Ghazala Yaqub, Zubi Sadiq, Almas Hamid, Saira Iqbal
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This paper is the very first report of three dual action hybrids synthesized by covalent linkage of carbazole based novel antibacterial compounds with efflux pump inhibitors i.e., indole acetic acid/gallic acid. Novel carbazole based antibacterial compounds were prepared first and then these were covalently linked with efflux pump inhibitors which leads to the successful formation of hybrids. All prepared compounds were evaluated for their bacterial cell killing capability against Escherichia coli, Staphylococcus aureus, Pasteurella multocida and Bacillus subtilis. Compound were effective against all tested bacterial strains at different concentrations. But when these compounds were linked with efflux pump inhibitors they showed dramatic enhancement in their bacterial cell killing potential and minimum inhibitory concentration of all hybrids ranges from 7.250 µg/mL to 0.0283 µg/mL.Keywords: antimicrobial assay, carbazole, dual action hybrids, efflux pump inhibitors
Procedia PDF Downloads 21042020 Performance of the Kindergarten Teachers and Its Relation to Pupils Achievement in Different Learning Areas
Authors: Mary Luna Mancao Ninal
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This study aimed to determine the performance of the kindergarten teachers and its relation to pupils’ achievement in different learning areas in the Division of Kabankalan City. Using the standardized assessment and evaluation of the Department of Education secondary data, 100 kinder teachers and 2901 kinder pupils were investigated to determine the performance of the kindergarten teachers based on their Competency–Based Performance Appraisal System for Teachers and the periodic assessment of kinder pupils collected as secondary data. Weighted mean, Pearson–r, chi-square, Analysis of Variance were used in the study. Findings revealed that the kindergarten teacher respondents were 26-31 years old and most of them were female and married; they spent teaching for two years and less and passed the Licensure Examination for Teachers. They were very satisfactory as to instructional competences, school, and home and community involvement, personal, social, and professional characteristics. It also revealed that performance of the kindergarten pupils on their period of assessment shows that they were slightly advanced in their development. It also shows that domain as to performance of the kindergarten pupils were average overall development. Based on the results, it is recommended that Kindergarten teacher must augment their educational qualification and pursue their graduate studies and must develop the total personality of the children for them to achieve high advanced development to become productive individual.Keywords: performance, kindergarten teacher, learning areas, professional, pupil
Procedia PDF Downloads 3572019 Effect of Progressive Type-I Right Censoring on Bayesian Statistical Inference of Simple Step–Stress Acceleration Life Testing Plan under Weibull Life Distribution
Authors: Saleem Z. Ramadan
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This paper discusses the effects of using progressive Type-I right censoring on the design of the Simple Step Accelerated Life testing using Bayesian approach for Weibull life products under the assumption of cumulative exposure model. The optimization criterion used in this paper is to minimize the expected pre-posterior variance of the PTH percentile time of failures. The model variables are the stress changing time and the stress value for the first step. A comparison between the conventional and the progressive Type-I right censoring is provided. The results have shown that the progressive Type-I right censoring reduces the cost of testing on the expense of the test precision when the sample size is small. Moreover, the results have shown that using strong priors or large sample size reduces the sensitivity of the test precision to the censoring proportion. Hence, the progressive Type-I right censoring is recommended in these cases as progressive Type-I right censoring reduces the cost of the test and doesn't affect the precision of the test a lot. Moreover, the results have shown that using direct or indirect priors affects the precision of the test.Keywords: reliability, accelerated life testing, cumulative exposure model, Bayesian estimation, progressive type-I censoring, Weibull distribution
Procedia PDF Downloads 5052018 Optimal Design of Redundant Hybrid Manipulator for Minimum Singularity
Authors: Arash Rahmani, Ahmad Ghanbari, Abbas Baghernezhad, Babak Safaei
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In the design of parallel manipulators, usually mean value of a dexterity measure over the workspace volume is considered as the objective function to be used in optimization algorithms. The mentioned indexes in a hybrid parallel manipulator (HPM) are quite complicated to solve thanks to infinite solutions for every point within the workspace of the redundant manipulators. In this paper, spatial isotropic design axioms are extended as a well-known method for optimum design of manipulators. An upper limit for the isotropy measure of HPM is calculated and instead of computing and minimizing isotropy measure, minimizing the obtained limit is considered. To this end, two different objective functions are suggested which are obtained from objective functions of comprising modules. Finally, by using genetic algorithm (GA), the best geometric parameters for a specific hybrid parallel robot which is composed of two modified Gough-Stewart platforms (MGSP) are achieved.Keywords: hybrid manipulator, spatial isotropy, genetic algorithm, optimum design
Procedia PDF Downloads 3362017 A Simulation Model to Analyze the Impact of Virtual Responsiveness in an E-Commerce Supply Chain
Authors: T. Godwin
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The design of a supply chain always entails the trade-off between responsiveness and efficiency. The launch of e-commerce has not only changed the way of shopping but also altered the supply chain design while trading off efficiency with responsiveness. A concept called ‘virtual responsiveness’ is introduced in the context of e-commerce supply chain. A simulation model is developed to compare actual responsiveness and virtual responsiveness to the customer in an e-commerce supply chain. The simulation is restricted to the movement of goods from the e-tailer to the customer. Customer demand follows a statistical distribution and is generated using inverse transformation technique. The two responsiveness schemes of the supply chain are compared in terms of the minimum number of inventory required at the e-tailer to fulfill the orders. Computational results show the savings achieved through virtual responsiveness. The insights gained from this study could be used to redesign e-commerce supply chain by incorporating virtual responsiveness. A part of the achieved cost savings could be passed back to the customer, thereby making the supply chain both effective and competitive.Keywords: e-commerce, simulation modeling, supply chain, virtual responsiveness
Procedia PDF Downloads 3442016 Dynamic Distribution Calibration for Improved Few-Shot Image Classification
Authors: Majid Habib Khan, Jinwei Zhao, Xinhong Hei, Liu Jiedong, Rana Shahzad Noor, Muhammad Imran
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Deep learning is increasingly employed in image classification, yet the scarcity and high cost of labeled data for training remain a challenge. Limited samples often lead to overfitting due to biased sample distribution. This paper introduces a dynamic distribution calibration method for few-shot learning. Initially, base and new class samples undergo normalization to mitigate disparate feature magnitudes. A pre-trained model then extracts feature vectors from both classes. The method dynamically selects distribution characteristics from base classes (both adjacent and remote) in the embedding space, using a threshold value approach for new class samples. Given the propensity of similar classes to share feature distributions like mean and variance, this research assumes a Gaussian distribution for feature vectors. Subsequently, distributional features of new class samples are calibrated using a corrected hyperparameter, derived from the distribution features of both adjacent and distant base classes. This calibration augments the new class sample set. The technique demonstrates significant improvements, with up to 4% accuracy gains in few-shot classification challenges, as evidenced by tests on miniImagenet and CUB datasets.Keywords: deep learning, computer vision, image classification, few-shot learning, threshold
Procedia PDF Downloads 662015 Statistical Analysis for Overdispersed Medical Count Data
Authors: Y. N. Phang, E. F. Loh
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Many researchers have suggested the use of zero inflated Poisson (ZIP) and zero inflated negative binomial (ZINB) models in modeling over-dispersed medical count data with extra variations caused by extra zeros and unobserved heterogeneity. The studies indicate that ZIP and ZINB always provide better fit than using the normal Poisson and negative binomial models in modeling over-dispersed medical count data. In this study, we proposed the use of Zero Inflated Inverse Trinomial (ZIIT), Zero Inflated Poisson Inverse Gaussian (ZIPIG) and zero inflated strict arcsine models in modeling over-dispersed medical count data. These proposed models are not widely used by many researchers especially in the medical field. The results show that these three suggested models can serve as alternative models in modeling over-dispersed medical count data. This is supported by the application of these suggested models to a real life medical data set. Inverse trinomial, Poisson inverse Gaussian, and strict arcsine are discrete distributions with cubic variance function of mean. Therefore, ZIIT, ZIPIG and ZISA are able to accommodate data with excess zeros and very heavy tailed. They are recommended to be used in modeling over-dispersed medical count data when ZIP and ZINB are inadequate.Keywords: zero inflated, inverse trinomial distribution, Poisson inverse Gaussian distribution, strict arcsine distribution, Pearson’s goodness of fit
Procedia PDF Downloads 5442014 Prediction Study of the Structural, Elastic and Electronic Properties of the Parent and Martensitic Phases of Nonferrous Ti, Zr, and Hf Pure Metals
Authors: Tayeb Chihi, Messaoud Fatmi
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We present calculations of the structural, elastic and electronic properties of nonferrous Ti, Zr, and Hf pure metals in both parent and martensite phases in bcc and hcp structures respectively. They are based on the generalized gradient approximation (GGA) within the density functional theory (DFT). The shear modulus, Young's modulus and Poisson's ratio for Ti, Zr, and Hf metals have were calculated and compared with the corresponding experimental values. Using elastic constants obtained from calculations GGA, the bulk modulus along the crystallographic axes of single crystals was calculated. This is in good agreement with experiment for Ti and Zr, whereas the hcp structure for Hf is a prediction. At zero temperature and zero pressure, the bcc crystal structure is found to be mechanically unstable for Ti, Zr, and Hf. In our calculations the hcp structures is correctly found to be stable at the equilibrium volume. In the electronic density of states (DOS), the smaller n(EF) is, the more stable the compound is. Therefore, in agreement with the results obtained from the total energy minimum.Keywords: Ti, Zr, Hf, pure metals, transformation, energy
Procedia PDF Downloads 3532013 National Health Insurance: An Exploratory Study of Patient Satisfaction
Authors: Nihayatul Munaa, Nyoman A. Damayanti
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This study seeks to understand what factors might influence a patient’s perception of health care under national health insurance in early implementation. In Indonesia, National Health Insurance was first implemented in 2014 and planned to achieve universal health coverage by 2019. However, the little understanding of this new policy lead to increase of complaint in hospital as a health care provider. This is a observational descriptive study with cross sectional design method. Data was collected through in-depth interview with 96 patient from Jemursari Islamic Hospital of Surabaya (Rumah Sakit Islam Jemursari Surabaya) who participate in National Health Insurance. Subject was selected by simple random sampling. The findings demonstrated that from five categories, 82,3% patient was satisfied in reliability aspect and 85,4% in assurance aspect, while in tangible, responsiveness and empathy aspect > 90% patient was satisfied. Meanwhile, in Indonesia, the minimum service standard of healthcare of patient satisfaction is 90%.Keywords: patient’s satisfaction, national health insurance, hospital, complaint
Procedia PDF Downloads 1912012 Compression Index Estimation by Water Content and Liquid Limit and Void Ratio Using Statistics Method
Authors: Lizhou Chen, Abdelhamid Belgaid, Assem Elsayed, Xiaoming Yang
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Compression index is essential in foundation settlement calculation. The traditional method for determining compression index is consolidation test which is expensive and time consuming. Many researchers have used regression methods to develop empirical equations for predicting compression index from soil properties. Based on a large number of compression index data collected from consolidation tests, the accuracy of some popularly empirical equations were assessed. It was found that primary compression index is significantly overestimated in some equations while it is underestimated in others. The sensitivity analyses of soil parameters including water content, liquid limit and void ratio were performed. The results indicate that the compression index obtained from void ratio is most accurate. The ANOVA (analysis of variance) demonstrates that the equations with multiple soil parameters cannot provide better predictions than the equations with single soil parameter. In other words, it is not necessary to develop the relationships between compression index and multiple soil parameters. Meanwhile, it was noted that secondary compression index is approximately 0.7-5.0% of primary compression index with an average of 2.0%. In the end, the proposed prediction equations using power regression technique were provided that can provide more accurate predictions than those from existing equations.Keywords: compression index, clay, settlement, consolidation, secondary compression index, soil parameter
Procedia PDF Downloads 1632011 Coherent Ku-Band Radar for Monitoring Ocean Waves
Authors: Richard Mitchell, Robert Mitchell, Thai Duong, Kyungbin Bae, Daegon Kim, Youngsub Lee, Inho Kim, Inho Park, Hyungseok Lee
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Although X-band radar is commonly used to measure the properties of ocean waves, the use of a higher frequency has several advantages, such as increased backscatter coefficient, better Doppler sensitivity, lower power, and a smaller package. A low-power Ku-band radar system was developed to demonstrate these advantages. It is fully coherent, and it interleaves short and long pulses to achieve a transmit duty ratio of 25%, which makes the best use of solid-state amplifiers. The range scales are 2 km, 4 km, and 8 km. The minimum range is 100 m, 200 m, and 400 m for the three range scales, and the range resolution is 4 m, 8 m, and 16 m for the three range scales. Measurements of the significant wave height, wavelength, wave period, and wave direction have been made using traditional 3D-FFT methods. Radar and ultrasonic sensor results collected over an extended period of time at a coastal site in South Korea are presented.Keywords: measurement of ocean wave parameters, Ku-band radar, coherent radar, compact radar
Procedia PDF Downloads 1692010 A Study of Effective Event Development and the Sustainability of Tourism Industry in Lagos State, Nigeria
Authors: Olajumoke Elizabeth Olawale-Olakunle
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This research examined effective event development on the sustainability of tourism in Lagos State. The objectives were to ascertain the implication of effective event development on cost, environmental innovations, opportunity for participants, job creation and working conditions. Also, there was a focus on employee participation and the sustainability of the tourism industry. However, the primary data were obtained via the use of structured questionnaire administered to the selected respondents. Simple random sampling was used to select the respondents, using the Yaro Yame formula. The formulated hypothesis was tested using Analysis of Variance (ANOVA) and Non-parametric chi-square. From the tests conducted, the results showed that effective event development has helped to reduce costs, bring about environmental innovations, offer unique opportunity among event participants, create jobs and promote better working conditions, and the influence it has on employee participation affects the sustainability of the tourism industry. Based on these results, it was concluded that effective event development helps to achieve sustainability in the tourism industry by reducing costs, ensuring efficient use of tourism resources and offers a unique opportunity among event participants. It was, therefore, recommended that events should be developed in such a way that it can help to reduce cost and help leverage the financial burdens of participants and stakeholders, thereby, achieving sustainability in the tourism industry.Keywords: tourism, hospitality, industry, development
Procedia PDF Downloads 3922009 Teacher's Health: Evaluation of the Health Status of Portuguese and Spanish Teachers
Authors: Liberata Borralho, Saúl N. de Jesus, Adelinda Candeias, Victória Fernández-Puig
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In the last decades, we have witnessed a deterioration in the health of teachers worldwide, reflecting the constant social, political and economic changes. The quality of teaching and the success of students depends on the health status of the teachers, which justifies the importance of periodically evaluating their health. With this purpose, the Teacher’s Health Questionnaire was applied to 15.394 teachers teaching in Portugal and Spain (6.208 Spanish and 9.186 Portuguese) of primary and secondary education (3.482 men, 11.911 women). This questionnaire is specific and includes both the main risks of the teaching profession and the manifestations of teacher well-being, according to the definition recommended by the World Health Organization. A descriptive analysis of the results was carried out, including a study of the dimensions and the differences according to some sociodemographic and professional variables, from an analysis of variance ANOVA, applying the Bonferroni correction. Cluster analysis (K-means) allowed us to obtain cutoff scores to assess health status. The results allow concluding that Portuguese teachers perceive a poor well-being in the performance of their professional activity and that more than half present manifestations in the various dimensions of health deterioration, highlighting the exhaustion and cognitive disorders. In turn, Spanish teachers demonstrate a high level of well-being, being the musculoskeletal dimensions and cognitive disorders the main manifestations of deterioration of health.Keywords: job prevention, occupational health, teacher’s health, teachers work risks, teacher’s well-being
Procedia PDF Downloads 2362008 Power Allocation in User-Centric Cell-Free Massive Multiple-Input Multiple-Output Systems with Limited Fronthaul Capacity
Authors: Siminfar Samakoush Galougah
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In this paper, we study two power allocation problems for an uplink user-centric (UC) cell-free massive multiple-input multiple-output (CF-mMIMO) system. Besides, we assume each access point (AP) is connected to a central processing unit (CPU) via a fronthaul link with limited capacity. To efficiently use the fronthaul capacity, two strategies for transmitting signals from APs to the CPU are employed, namely, compress-forward estimate (CFE), estimate-compress-forward (ECF). The capacity of the aforementioned strategies in user-centric CF-mMIMO is drived. Then, we solved the two power allocation problems with minimum Spectral Efficiency (SE) and sum-SE maximization objectives for ECF and CFE strategies.Keywords: cell-free massive MIMO, limited capacity fronthaul, spectral efficiency
Procedia PDF Downloads 712007 Contact Temperature of Sliding Surfaces in AISI 316 Austenitic Stainless Steel During PIN on Disk Dry Wear Testing
Authors: Dler Abdullah Ahmed, Zozan Ahmed Mohammed
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This study looked into contact surface temperature during a pin-on-disk test. Friction and wear between sliding surfaces raised the temperature differential between the contact surface and ambient temperatures Tdiff. Tdiff was significantly influenced by wear test variables. Tdiff rose with the increase of sliding speed and applied load while dropped with the increase in ambient temperature. The highest Tdiff was 289°C during the tests at room temperature and 2.5 m/s sliding speed, while the minimum was only 24 °C during the tests at 400°C and 0.5 m/s. However, the maximum contact temperature Tmax was found during tests conducted at high ambient temperatures. The Tmax was estimated based on the theoretical equation. The comparison of experimental and theoretical Tmax data revealed good agreement.Keywords: pin on disk test, contact temperature, wear, sliding surface, friction, ambient temperature
Procedia PDF Downloads 822006 An Inverse Optimal Control Approach for the Nonlinear System Design Using ANN
Authors: M. P. Nanda Kumar, K. Dheeraj
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The design of a feedback controller, so as to minimize a given performance criterion, for a general non-linear dynamical system is difficult; if not impossible. But for a large class of non-linear dynamical systems, the open loop control that minimizes a performance criterion can be obtained using calculus of variations and Pontryagin’s minimum principle. In this paper, the open loop optimal trajectories, that minimizes a given performance measure, is used to train the neural network whose inputs are state variables of non-linear dynamical systems and the open loop optimal control as the desired output. This trained neural network is used as the feedback controller. In other words, attempts are made here to solve the “inverse optimal control problem” by using the state and control trajectories that are optimal in an open loop sense.Keywords: inverse optimal control, radial basis function, neural network, controller design
Procedia PDF Downloads 5532005 The Effect of Market Orientation on Business Performance of Auto Parts Industry
Authors: Vithaya Intraphimol
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The purpose of this study is to investigate the relationship between market orientation and business performance through innovations that include product innovation and process innovation. Auto parts and accessories companies in Thailand were used as sample for this investigation. Survey research with structured questionnaire was used as the key instrument in collecting the data. The structural equation modeling (SEM) was assigned test the hypotheses. The sample size in this study requires the minimum sample size of 200. The result found that competitor orientation, and interfunctional coordination has an effect on product innovation. Moreover, interfunctional coordination has an effect on process innovation, and return on asset. This indicates that within- firm coordination has crucial to firms’ performances. The implication for practice, firms should support interfunctional coordination that members of different functional areas of an organization communicate and work together for the creation of value to target buyers they may have better profitability.Keywords: auto parts industry, business performance, innovations, market orientation
Procedia PDF Downloads 3122004 A Hybrid Data-Handler Module Based Approach for Prioritization in Quality Function Deployment
Authors: P. Venu, Joeju M. Issac
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Quality Function Deployment (QFD) is a systematic technique that creates a platform where the customer responses can be positively converted to design attributes. The accuracy of a QFD process heavily depends on the data that it is handling which is captured from customers or QFD team members. Customized computer programs that perform Quality Function Deployment within a stipulated time have been used by various companies across the globe. These programs heavily rely on storage and retrieval of the data on a common database. This database must act as a perfect source with minimum missing values or error values in order perform actual prioritization. This paper introduces a missing/error data handler module which uses Genetic Algorithm and Fuzzy numbers. The prioritization of customer requirements of sesame oil is illustrated and a comparison is made between proposed data handler module-based deployment and manual deployment.Keywords: hybrid data handler, QFD, prioritization, module-based deployment
Procedia PDF Downloads 2972003 Improving Coverage in Wireless Sensor Networks Using Particle Swarm Optimization Algorithm
Authors: Ehsan Abdolzadeh, Sanaz Nouri, Siamak Khalaj
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Today WSNs have many applications in different fields like the environment, military operations, discoveries, monitoring operations, and so on. Coverage size and energy consumption are the important challenges that these networks need to face. This paper tries to solve the problem of coverage with a requirement of k-coverage and minimum energy consumption. In order to minimize energy consumption, visual sensor networks have been used that observe and process just those targets that are located in their view direction. As a result, sensor rotations have decreased, and subsequently, energy consumption has been minimized. To solve the problem of coverage particle swarm optimization, coverage optimization has been able to ensure coverage requirement together with minimizing sensor rotations while meeting the problem requirement of k≤14. So energy consumption has decreased, and this could extend the sensors’ lifetime subsequently.Keywords: K coverage, particle union optimization algorithm, wireless sensor networks, visual sensor networks
Procedia PDF Downloads 1152002 Analyzing Antimicrobial Power of Cotula cinerea Essential Oil: Case of Western Algeria
Authors: A. Abdenbi, B. Dennai, B. Touati, M. Bouaaza, A. Saad
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The essential oils of many plants have become popular in recent years and their bioactive principles have recently won several industry sectors, however their use as antibacterial and anti fungal agents has been reported. This study focuses on the physico chemical and phyto chemical with a study of the antimicrobial activity of essential oils of aromatic and medicinal plant of southwest Algeria, this essential oil was obtained by hydro-distillation of aerial parts of Cotula cinerea, belonging to the Asteraceae family, it is very extensive in the spring season in a region called Kenadza road, located 12km from Bechar. Variable anti fungal activity of the essential oil of Cotula cinerea (yield 2%) were revealed about four fungal strains, the minimum inhibitory concentrations of essential oils were determined by the method of dilution in agar. Significant fungal sensitivity of Penicillium sp with an inhibition of 32.3 mm area.Keywords: Cotula cinerea, essential oil, physico- chemical analysis and phyto- chemical, anti fungal power
Procedia PDF Downloads 4142001 Antibacterial and Anti-Biofilm Activity of Papain Hydrolysed Camel Milk Whey and Its Fractions
Authors: M. Abdel-Hamid, P. Saporito, R. V. Mateiu, A. Osman, E. Romeih, H. Jenssen
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Camel milk whey (CMW) was hydrolyzed with papain from Carica papaya and fractionated by size exclusion chromatography (SEC). The antibacterial and anti-biofilm activity of the CMW, Camel milk whey hydrolysate (CMWH) and the obtained SEC-fractions was assessed against Pseudomonas aeruginosa and Methicillin-resistant Staphylococcus aureus (MRSA). SEC-F2 (fraction 2) exhibited antibacterial effectiveness against MRSA and P. aeruginosa with the minimum inhibitory concentration of 0.31 and 0.156 mg/ml, respectively. Furthermore, SEC-F2 significantly decreased biofilm biomass by 71% and 83 % for MRSA and P. aeruginosa in a crystal violet microplate assay. Scanning electron microscopy showed that the SEC-F2 caused changes in the treated bacterial cells. Additionally, LC/MS analysis was used to characterize the peptides of SEC-F2. Two major peptides were detected in SEC-F2 having masses of 414.05 Da and 456.06 Da. In conclusion, this study has demonstrated that hydrolysis of CMW with papain generates small and extremely potent antibacterial and anti-biofilm peptides against both MRSA and P. aeruginosa.Keywords: camel milk, whey proteins, antibacterial peptide, anti-biofilm
Procedia PDF Downloads 2202000 Effect of Modeling of Hydraulic Form Loss Coefficient to Break on Emergency Core Coolant Bypass
Authors: Young S. Bang, Dong H. Yoon, Seung H. Yoo
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Emergency Core Coolant Bypass (ECC Bypass) has been regarded as an important phenomenon to peak cladding temperature of large-break loss-of-coolant-accidents (LBLOCA) in nuclear power plants (NPP). A modeling scheme to address the ECC Bypass phenomena and the calculation of LBLOCA using that scheme are discussed in the present paper. A hydraulic form loss coefficient (HFLC) from the reactor vessel downcomer to the broken cold leg is predicted by the computational fluid dynamics (CFD) code with a variation of the void fraction incoming from the downcomer. The maximum, mean, and minimum values of FLC are derived from the CFD results and are incorporated into the LBLOCA calculation using a system thermal-hydraulic code, MARS-KS. As a relevant parameter addressing the ECC Bypass phenomena, the FLC to the break and its range are proposed.Keywords: CFD analysis, ECC bypass, hydraulic form loss coefficient, system thermal-hydraulic code
Procedia PDF Downloads 2301999 An Epsilon Hierarchical Fuzzy Twin Support Vector Regression
Authors: Arindam Chaudhuri
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The research presents epsilon- hierarchical fuzzy twin support vector regression (epsilon-HFTSVR) based on epsilon-fuzzy twin support vector regression (epsilon-FTSVR) and epsilon-twin support vector regression (epsilon-TSVR). Epsilon-FTSVR is achieved by incorporating trapezoidal fuzzy numbers to epsilon-TSVR which takes care of uncertainty existing in forecasting problems. Epsilon-FTSVR determines a pair of epsilon-insensitive proximal functions by solving two related quadratic programming problems. The structural risk minimization principle is implemented by introducing regularization term in primal problems of epsilon-FTSVR. This yields dual stable positive definite problems which improves regression performance. Epsilon-FTSVR is then reformulated as epsilon-HFTSVR consisting of a set of hierarchical layers each containing epsilon-FTSVR. Experimental results on both synthetic and real datasets reveal that epsilon-HFTSVR has remarkable generalization performance with minimum training time.Keywords: regression, epsilon-TSVR, epsilon-FTSVR, epsilon-HFTSVR
Procedia PDF Downloads 3751998 Social Influences on Americans' Mask-Wearing Behavior during COVID-19
Authors: Ruoya Huang, Ruoxian Huang, Edgar Huang
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Based on a convenience sample of 2,092 participants from across all 50 states of the United States, a survey was conducted to explore Americans’ mask-wearing behaviors during COVID-19 according to their political convictions, religious beliefs, and ethnic cultures from late July to early September, 2020. The purpose of the study is to provide evidential support for government policymaking so as to drive up more effective public policies by taking into consideration the variance in these social factors. It was found that the respondents’ party affiliation or preference, religious belief, and ethnicity, in addition to their health condition, gender, level of concern of contracting COVID-19, all affected their mask-wearing habits both in March, the initial coronavirus outbreak stage, and in August, when mask-wearing had been made mandatory by state governments. The study concludes that pandemic awareness campaigns must be run among all citizens, especially among African Americans, Muslims, and Republicans, who have the lowest rates of wearing masks, in order to protect themselves and others. It is recommended that complementary cognitive bias awareness programs should be implemented in non-Black and non-Muslim communities to eliminate social concerns that deter them from wearing masks.Keywords: COVID-19 pandemic, ethnicity, mask-wearing, policymaking implications, political affiliations, religious beliefs, United States
Procedia PDF Downloads 2331997 Optimal Peer-to-Peer On-Orbit Refueling Mission Planning with Complex Constraints
Authors: Jing Yu, Hongyang Liu, Dong Hao
Abstract:
On-Orbit Refueling is of great significance in extending space crafts' lifetime. The problem of minimum-fuel, time-fixed, Peer-to-Peer On-Orbit Refueling mission planning is addressed here with the particular aim of assigning fuel-insufficient satellites to the fuel-sufficient satellites and optimizing each rendezvous trajectory. Constraints including perturbation, communication link, sun illumination, hold points for different rendezvous phases, and sensor switching are considered. A planning model has established as well as a two-level solution method. The upper level deals with target assignment based on fuel equilibrium criterion, while the lower level solves constrained trajectory optimization using special maneuver strategies. Simulations show that the developed method could effectively resolve the Peer-to-Peer On-Orbit Refueling mission planning problem and deal with complex constraints.Keywords: mission planning, orbital rendezvous, on-orbit refueling, space mission
Procedia PDF Downloads 226