Search results for: distribution patterns
6878 Combining Shallow and Deep Unsupervised Machine Learning Techniques to Detect Bad Actors in Complex Datasets
Authors: Jun Ming Moey, Zhiyaun Chen, David Nicholson
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Bad actors are often hard to detect in data that imprints their behaviour patterns because they are comparatively rare events embedded in non-bad actor data. An unsupervised machine learning framework is applied here to detect bad actors in financial crime datasets that record millions of transactions undertaken by hundreds of actors (<0.01% bad). Specifically, the framework combines ‘shallow’ (PCA, Isolation Forest) and ‘deep’ (Autoencoder) methods to detect outlier patterns. Detection performance analysis for both the individual methods and their combination is reported.Keywords: detection, machine learning, deep learning, unsupervised, outlier analysis, data science, fraud, financial crime
Procedia PDF Downloads 746877 Impact of Very Small Power Producers (VSPP) on Control and Protection System in Distribution Networks
Authors: Noppatee Sabpayakom, Somporn Sirisumrannukul
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Due to incentive policies to promote renewable energy and energy efficiency, high penetration levels of very small power producers (VSPP) located in distribution networks have imposed technical barriers and established new requirements for protection and control of the networks. Although VSPPs have economic and environmental benefit, they may introduce negative effects and cause several challenges on the issue of protection and control system. This paper presents comprehensive studies of possible impacts on control and protection systems based on real distribution systems located in a metropolitan area. A number of scenarios were examined primarily focusing on state of islanding, and un-disconnected VSPP during faults. It is shown that without proper measures to address the issues, the system would be unable to maintain its integrity of electricity power supply for disturbance incidents.Keywords: control and protection systems, distributed generation, renewable energy, very small power producers
Procedia PDF Downloads 4616876 Implementation of Statistical Parameters to Form an Entropic Mathematical Models
Authors: Gurcharan Singh Buttar
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It has been discovered that although these two areas, statistics, and information theory, are independent in their nature, they can be combined to create applications in multidisciplinary mathematics. This is due to the fact that where in the field of statistics, statistical parameters (measures) play an essential role in reference to the population (distribution) under investigation. Information measure is crucial in the study of ambiguity, assortment, and unpredictability present in an array of phenomena. The following communication is a link between the two, and it has been demonstrated that the well-known conventional statistical measures can be used as a measure of information.Keywords: probability distribution, entropy, concavity, symmetry, variance, central tendency
Procedia PDF Downloads 1426875 Surface Pressure Distribution of a Flapped-Airfoil for Different Momentum Injection at the Leading Edge
Authors: Mohammad Mashud, S. M. Nahid Hasan
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The aim of the research work is to modify the NACA 4215 airfoil with flap and rotary cylinder at the leading edge of the airfoil and experimentally study the static pressure distribution over the airfoil completed with flap and leading-edge vortex generator. In this research, NACA 4215 wing model has been constructed by generating the profile geometry using the standard equations and design software such as AutoCAD and SolidWorks. To perform the experiment, three wooden models are prepared and tested in subsonic wind tunnel. The experiments were carried out in various angles of attack. Flap angle and momentum injection rate are changed to observe the characteristics of pressure distribution. In this research, a new concept of flow separation control mechanism has been introduced to improve the aerodynamic characteristics of airfoil. Control of flow separation over airfoil which experiences a vortex generator (rotating cylinder) at the leading edge of airfoil is experimentally simulated under the effects of momentum injection. The experimental results show that the flow separation control is possible by the proposed mechanism, and benefits can be achieved by momentum injection technique. The wing performance is significantly improved due to control of flow separation by momentum injection method.Keywords: airfoil, momentum injection, flap, pressure distribution
Procedia PDF Downloads 1266874 Nonstationary Modeling of Extreme Precipitation in the Wei River Basin, China
Authors: Yiyuan Tao
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Under the impact of global warming together with the intensification of human activities, the hydrological regimes may be altered, and the traditional stationary assumption was no longer satisfied. However, most of the current design standards of water infrastructures were still based on the hypothesis of stationarity, which may inevitably result in severe biases. Many critical impacts of climate on ecosystems, society, and the economy are controlled by extreme events rather than mean values. Therefore, it is of great significance to identify the non-stationarity of precipitation extremes and model the precipitation extremes in a nonstationary framework. The Wei River Basin (WRB), located in a continental monsoon climate zone in China, is selected as a case study in this study. Six extreme precipitation indices were employed to investigate the changing patterns and stationarity of precipitation extremes in the WRB. To identify if precipitation extremes are stationary, the Mann-Kendall trend test and the Pettitt test, which is used to examine the occurrence of abrupt changes are adopted in this study. Extreme precipitation indices series are fitted with non-stationary distributions that selected from six widely used distribution functions: Gumbel, lognormal, Weibull, gamma, generalized gamma and exponential distributions by means of the time-varying moments model generalized additive models for location, scale and shape (GAMLSS), where the distribution parameters are defined as a function of time. The results indicate that: (1) the trends were not significant for the whole WRB, but significant positive/negative trends were still observed in some stations, abrupt changes for consecutive wet days (CWD) mainly occurred in 1985, and the assumption of stationarity is invalid for some stations; (2) for these nonstationary extreme precipitation indices series with significant positive/negative trends, the GAMLSS models are able to capture well the temporal variations of the indices, and perform better than the stationary model. Finally, the differences between the quantiles of nonstationary and stationary models are analyzed, which highlight the importance of nonstationary modeling of precipitation extremes in the WRB.Keywords: extreme precipitation, GAMLSSS, non-stationary, Wei River Basin
Procedia PDF Downloads 1086873 Patterns Obtained by Using Knitting Technique in Textile Crafts
Authors: Özlem Erzurumlu, Nazan Oskay, Ece Melek
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Knitting which is one of the textile manufacturing techniques is manufactured by using the system of single yarn. Knitting wares consisting of loops structurally have flexible structures. Knitting can be shaped and given volume easily due to increasing or decreasing the number of loops, being manufactured in circular form and its flexible structure. While the knitting wares are basically being manufactured to meet the requirements, it takes its place in the art field overflowing outside of industrial production later. Textile artist ensures his ideas to convert into artistic product by using textiles and non-textiles with aesthetic concerns and creative impulses. When textile crafts are observed at the present time we see that knitting technique has an extensive area of use such as sculpture, panel, installation art and performing art. It is examined how the knitting technique is used in textile crafts observing patterns obtained by this technique in textile crafts in this study.Keywords: art, textile, knitting art, textile crafts
Procedia PDF Downloads 6866872 A Novel NRIS Index to Evaluate Brain Activity in Prefrontal Regions While Listening to First and Second Languages for Long Time Periods
Authors: Kensho Takahashi, Ko Watanabe, Takashi Kaburagi, Hiroshi Tanaka, Kajiro Watanabe, Yosuke Kurihara
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Near-infrared spectroscopy (NIRS) has been widely used as a non-invasive method to measure brain activity, but it is corrupted by baseline drift noise. Here we present a method to measure regional cerebral blood flow as a derivative of NIRS output. We investigate whether, when listening to languages, blood flow can reasonably localize and represent regional brain activity or not. The prefrontal blood flow distribution pattern when advanced second-language listeners listened to a second language (L2) was most similar to that when listening to their first language (L1) among the patterns of mean and standard deviation. In experiments with 25 healthy subjects, the maximum blood flow was localized to the left BA46 of advanced listeners. The blood flow presented is robust to baseline drift and stably localizes regional brain activity.Keywords: NIRS, oxy-hemoglobin, baseline drift, blood flow, working memory, BA46, first language, second language
Procedia PDF Downloads 5426871 On-Chip Sensor Ellipse Distribution Method and Equivalent Mapping Technique for Real-Time Hardware Trojan Detection and Location
Authors: Longfei Wang, Selçuk Köse
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Hardware Trojan becomes great concern as integrated circuit (IC) technology advances and not all manufacturing steps of an IC are accomplished within one company. Real-time hardware Trojan detection is proven to be a feasible way to detect randomly activated Trojans that cannot be detected at testing stage. On-chip sensors serve as a great candidate to implement real-time hardware Trojan detection, however, the optimization of on-chip sensors has not been thoroughly investigated and the location of Trojan has not been carefully explored. On-chip sensor ellipse distribution method and equivalent mapping technique are proposed based on the characteristics of on-chip power delivery network in this paper to address the optimization and distribution of on-chip sensors for real-time hardware Trojan detection as well as to estimate the location and current consumption of hardware Trojan. Simulation results verify that hardware Trojan activation can be effectively detected and the location of a hardware Trojan can be efficiently estimated with less than 5% error for a realistic power grid using our proposed methods. The proposed techniques therefore lay a solid foundation for isolation and even deactivation of hardware Trojans through accurate location of Trojans.Keywords: hardware trojan, on-chip sensor, power distribution network, power/ground noise
Procedia PDF Downloads 3776870 Estimating the Life-Distribution Parameters of Weibull-Life PV Systems Utilizing Non-Parametric Analysis
Authors: Saleem Z. Ramadan
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In this paper, a model is proposed to determine the life distribution parameters of the useful life region for the PV system utilizing a combination of non-parametric and linear regression analysis for the failure data of these systems. Results showed that this method is dependable for analyzing failure time data for such reliable systems when the data is scarce.Keywords: masking, bathtub model, reliability, non-parametric analysis, useful life
Procedia PDF Downloads 5466869 Estimation of Stress-Strength Parameter for Burr Type XII Distribution Based on Progressive Type-II Censoring
Authors: A. M. Abd-Elfattah, M. H. Abu-Moussa
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In this paper, the estimation of stress-strength parameter R = P(Y < X) is considered when X; Y the strength and stress respectively are two independent random variables of Burr Type XII distribution. The samples taken for X and Y are progressively censoring of type II. The maximum likelihood estimator (MLE) of R is obtained when the common parameter is unknown. But when the common parameter is known the MLE, uniformly minimum variance unbiased estimator (UMVUE) and the Bayes estimator of R = P(Y < X) are obtained. The exact condence interval of R based on MLE is obtained. The performance of the proposed estimators is compared using the computer simulation.Keywords: Burr Type XII distribution, progressive type-II censoring, stress-strength model, unbiased estimator, maximum-likelihood estimator, uniformly minimum variance unbiased estimator, confidence intervals, Bayes estimator
Procedia PDF Downloads 4426868 Unsupervised Learning and Similarity Comparison of Water Mass Characteristics with Gaussian Mixture Model for Visualizing Ocean Data
Authors: Jian-Heng Wu, Bor-Shen Lin
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The temperature-salinity relationship is one of the most important characteristics used for identifying water masses in marine research. Temperature-salinity characteristics, however, may change dynamically with respect to the geographic location and is quite sensitive to the depth at the same location. When depth is taken into consideration, however, it is not easy to compare the characteristics of different water masses efficiently for a wide range of areas of the ocean. In this paper, the Gaussian mixture model was proposed to analyze the temperature-salinity-depth characteristics of water masses, based on which comparison between water masses may be conducted. Gaussian mixture model could model the distribution of a random vector and is formulated as the weighting sum for a set of multivariate normal distributions. The temperature-salinity-depth data for different locations are first used to train a set of Gaussian mixture models individually. The distance between two Gaussian mixture models can then be defined as the weighting sum of pairwise Bhattacharyya distances among the Gaussian distributions. Consequently, the distance between two water masses may be measured fast, which allows the automatic and efficient comparison of the water masses for a wide range area. The proposed approach not only can approximate the distribution of temperature, salinity, and depth directly without the prior knowledge for assuming the regression family, but may restrict the complexity by controlling the number of mixtures when the amounts of samples are unevenly distributed. In addition, it is critical for knowledge discovery in marine research to represent, manage and share the temperature-salinity-depth characteristics flexibly and responsively. The proposed approach has been applied to a real-time visualization system of ocean data, which may facilitate the comparison of water masses by aggregating the data without degrading the discriminating capabilities. This system provides an interface for querying geographic locations with similar temperature-salinity-depth characteristics interactively and for tracking specific patterns of water masses, such as the Kuroshio near Taiwan or those in the South China Sea.Keywords: water mass, Gaussian mixture model, data visualization, system framework
Procedia PDF Downloads 1286867 Assessing Public Open Spaces Availability and Distribution in a Socially Challenged City: A Case Study of Riyadh, Saudi Arabia
Authors: Abdulwahab Alalyani, Mahbub Rashid
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Public Open Space (POS) availability and distribution among urban communities have a central role to promotes community health. However, growing health challenges in a city would raise attention to the planning quality of these community's assets. This research aims to measure the existing availability and distribution equity of POS in the context of Saudi Arabia using Riyadh city as a case study. The methodology for the POS availability was by calculating the total POS with respect to the population total (m²/inhabitant). All POS were mapped using geographical information systems (GIS), and the total area availability of POS was compared to global, regional, and local standards. To evaluate the significant differences in POS availability across low, medium, and high-income Riyadh neighborhoods, we used a One-way ANOVA analysis of covariance to test the differences. The results are as follows; POS availability was lower than global standers. Riyadh has only 1.40m² per capita of POS. Spatial equity of the availability were significantly different among Riyadh neighborhoods based on socioeconomic status. The future development of POS should be focused on increasing general POS availability and should be given priority to those low-income and unhealthy communities. Accessibility indicators of POS should be considered in future studies.Keywords: open spaces availability, open spaces distribution, spatial equity, healthy city, Riyadh City
Procedia PDF Downloads 896866 A Proposed Algorithm for Obtaining the Map of Subscribers’ Density Distribution for a Mobile Wireless Communication Network
Authors: C. Temaneh-Nyah, F. A. Phiri, D. Karegeya
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This paper presents an algorithm for obtaining the map of subscriber’s density distribution for a mobile wireless communication network based on the actual subscriber's traffic data obtained from the base station. This is useful in statistical characterization of the mobile wireless network.Keywords: electromagnetic compatibility, statistical analysis, simulation of communication network, subscriber density
Procedia PDF Downloads 2976865 MigrationR: An R Package for Analyzing Bird Migration Data Based on Satellite Tracking
Authors: Xinhai Li, Huidong Tian, Yumin Guo
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Bird migration is fantastic natural phenomenon. In recent years, the use of GPS transmitters has generated a vast amount of data, and the Movebank platform has made these data publicly accessible. For researchers, what they need are data analysis tools. Although there are approximately 90 R packages dedicated to animal movement analysis, the capacity for comprehensive processing of bird migration data remains limited. Hence, we introduce a novel package called migrationR. This package enables the calculation of movement speed, direction, changes in direction, flight duration, daily and annual movement distances. Furthermore, it can pinpoint the starting and ending dates of migration, estimate nest site locations and stopovers, and visualize movement trajectories at various time scales. migrationR distinguishes individuals through NMDS (non-metric multidimensional scaling) coordinates based on movement variables such as speed, flight duration, path tortuosity, and migration timing. A distinctive aspect of the package is the development of a hetero-occurrences species distribution model that takes into account the daily rhythm of individual birds across different landcover types. Habitat use for foraging and roosting differs significantly for many waterbirds. For example, White-naped Cranes at Poyang Lake in China typically forage in croplands and roost in shallow water areas. Both of these occurrence types are of equal importance. Optimal habitats consist of a combination of crop lands and shallow waters, whereas suboptimal habitats lack both, which necessitates birds to fly extensively. With migrationR, we conduct species distribution modeling for foraging and roosting separately and utilize the moving distance between crop lands and shallow water areas as an index of overall habitat suitability. This approach offers a more nuanced understanding of the habitat requirements for migratory birds and enhances our ability to analyze and interpret their movement patterns effectively. The functions of migrationR are demonstrated using our own tracking data of 78 White-naped Crane individuals from 2014 to 2023, comprising over one million valid locations in total. migrationR can be installed from a GitHub repository by executing the following command: remotes::install_github("Xinhai-Li/migrationR").Keywords: bird migration, hetero-occurrences species distribution model, migrationR, R package, satellite telemetry
Procedia PDF Downloads 466864 Fused Deposition Modeling Printing of Bioinspired Triply Periodic Minimal Surfaces Based Polyvinylidene Fluoride Materials for Scaffold Development in Biomedical Application
Authors: Farusil Najeeb Mullaveettil, Rolanas Dauksevicius
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Cellular structures produced by additive manufacturing have earned wide research attention due to their unique specific strength and energy absorption potentiality. The literature review concludes that pattern type and density are vital parameters that affect the mechanical properties of parts formed by additive manufacturing techniques and have an influence on printing time and material consumption. Fused deposition modeling technique (FDM) is used here to produce Polyvinylidene fluoride (PVDF) parts. In this work, patterns are based on triply periodic minimal surfaces (TPMS) produced by PVDF-based filaments using the FDM technique. PVDF homopolymer filament Fluorinar-H™ and PVDF copolymer filament Fluorinar-C™ are printed with three types of TPMS patterns. The patterns printed are Gyroid, Schwartz diamond, and Schwartz primitive. Tensile, flexural, and compression tests under quasi-static loading conditions are performed in compliance with ISO standards. The investigation elucidates the deformation mechanisms and a study that establishes a relationship between the printed and nominal specimens' dimensional accuracy. In comparison to the examined TPMS pattern, Schwartz diamond showed a higher relative elastic modulus and strength than the other patterns in tensile loading, and the Gyroid pattern showed the highest mechanical characteristics in flexural loading. The concluded results could be utilized to produce informed cellular designs for biomedical and mechanical applications.Keywords: additive manufacturing, FDM, PVDF, gyroid, schwartz primitive, schwartz diamond, TPMS, tensile, flexural
Procedia PDF Downloads 1266863 Energy Deposited by Secondary Electrons Generated by Swift Proton Beams through Polymethylmethacrylate
Authors: Maurizio Dapor, Isabel Abril, Pablo de Vera, Rafael Garcia-Molina
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The ionization yield of ion tracks in polymers and bio-molecular systems reaches a maximum, known as the Bragg peak, close to the end of the ion trajectories. Along the path of the ions through the materials, many electrons are generated, which produce a cascade of further ionizations and, consequently, a shower of secondary electrons. Among these, very low energy secondary electrons can produce damage in the biomolecules by dissociative electron attachment. This work deals with the calculation of the energy distribution of electrons produced by protons in a sample of polymethylmethacrylate (PMMA), a material that is used as a phantom for living tissues in hadron therapy. PMMA is also of relevance for microelectronics in CMOS technologies and as a photoresist mask in electron beam lithography. We present a Monte Carlo code that, starting from a realistic description of the energy distribution of the electrons ejected by protons moving through PMMA, simulates the entire cascade of generated secondary electrons. By following in detail the motion of all these electrons, we find the radial distribution of the energy that they deposit in PMMA for several initial proton energies characteristic of the Bragg peak.Keywords: Monte Carlo method, secondary electrons, energetic ions, ion-beam cancer therapy, ionization cross section, polymethylmethacrylate, proton beams, secondary electrons, radial energy distribution
Procedia PDF Downloads 2686862 A Hybrid Model of Structural Equation Modelling-Artificial Neural Networks: Prediction of Influential Factors on Eating Behaviors
Authors: Maryam Kheirollahpour, Mahmoud Danaee, Amir Faisal Merican, Asma Ahmad Shariff
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Background: The presence of nonlinearity among the risk factors of eating behavior causes a bias in the prediction models. The accuracy of estimation of eating behaviors risk factors in the primary prevention of obesity has been established. Objective: The aim of this study was to explore the potential of a hybrid model of structural equation modeling (SEM) and Artificial Neural Networks (ANN) to predict eating behaviors. Methods: The Partial Least Square-SEM (PLS-SEM) and a hybrid model (SEM-Artificial Neural Networks (SEM-ANN)) were applied to evaluate the factors affecting eating behavior patterns among university students. 340 university students participated in this study. The PLS-SEM analysis was used to check the effect of emotional eating scale (EES), body shape concern (BSC), and body appreciation scale (BAS) on different categories of eating behavior patterns (EBP). Then, the hybrid model was conducted using multilayer perceptron (MLP) with feedforward network topology. Moreover, Levenberg-Marquardt, which is a supervised learning model, was applied as a learning method for MLP training. The Tangent/sigmoid function was used for the input layer while the linear function applied for the output layer. The coefficient of determination (R²) and mean square error (MSE) was calculated. Results: It was proved that the hybrid model was superior to PLS-SEM methods. Using hybrid model, the optimal network happened at MPLP 3-17-8, while the R² of the model was increased by 27%, while, the MSE was decreased by 9.6%. Moreover, it was found that which one of these factors have significantly affected on healthy and unhealthy eating behavior patterns. The p-value was reported to be less than 0.01 for most of the paths. Conclusion/Importance: Thus, a hybrid approach could be suggested as a significant methodological contribution from a statistical standpoint, and it can be implemented as software to be able to predict models with the highest accuracy.Keywords: hybrid model, structural equation modeling, artificial neural networks, eating behavior patterns
Procedia PDF Downloads 1276861 A Discourse on the Rhythmic Pattern Employed in Yoruba Sakara Music of Nigeria
Authors: Oludare Olupemi Ezekiel
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This research examines the rhythmic structure of Sakara music by tracing its roots and analyzing the various rhythmic patterns of this neo-traditional genre, as well as the contributions of the major exponents and contemporary practitioners, using these as a model for understanding and establishing African rhythms. Biography of the major exponents and contemporary practitioners, interviews and participant observational methods were used to elicit information. Samples of the genre which were chosen at random were transcribed, notated and analyzed for academic use and documentation. The research affirmed that rhythms such as the Hemiola, Cross-rhythm, Clave or Bell rhythm, Percussive, Speech and Melodic rhythm and other relevant rhythmic theories were prevalent and applicable to Sakara music, while making important contributions to musical scholarship through its analysis of the music. The analysis and discussions carried out in the research pointed towards a conclusion that the Yoruba musicians are guided by some preconceptions and sound musical considerations in making their rhythmic patterns, used as compositional techniques and not mere incidental occurrence. These rhythmic patterns, with its consequential socio-cultural connotations, enhance musical values and national identity in Nigeria. The study concludes by recommending that musicologists need to carry out more research into this and other neo-traditional genres in order to advance the globalisation of African music.Keywords: compositional techniques, globalisation, identity, neo-traditional, rhythmic theory, Sakara music
Procedia PDF Downloads 4236860 A Biomimetic Approach for the Multi-Objective Optimization of Kinetic Façade Design
Authors: Do-Jin Jang, Sung-Ah Kim
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A kinetic façade responds to user requirements and environmental conditions. In designing a kinetic façade, kinetic patterns play a key role in determining its performance. This paper proposes a biomimetic method for the multi-objective optimization for kinetic façade design. The autonomous decentralized control system is combined with flocking algorithm. The flocking agents are autonomously reacting to sensor values and bring about kinetic patterns changing over time. A series of experiments were conducted to verify the potential and limitations of the flocking based decentralized control. As a result, it could show the highest performance balancing multiple objectives such as solar radiation and openness among the comparison group.Keywords: biomimicry, flocking algorithm, autonomous decentralized control, multi-objective optimization
Procedia PDF Downloads 4996859 Unbalanced Distribution Optimal Power Flow to Minimize Losses with Distributed Photovoltaic Plants
Authors: Malinwo Estone Ayikpa
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Electric power systems are likely to operate with minimum losses and voltage meeting international standards. This is made possible generally by control actions provide by automatic voltage regulators, capacitors and transformers with on-load tap changer (OLTC). With the development of photovoltaic (PV) systems technology, their integration on distribution networks has increased over the last years to the extent of replacing the above mentioned techniques. The conventional analysis and simulation tools used for electrical networks are no longer able to take into account control actions necessary for studying distributed PV generation impact. This paper presents an unbalanced optimal power flow (OPF) model that minimizes losses with association of active power generation and reactive power control of single-phase and three-phase PV systems. Reactive power can be generated or absorbed using the available capacity and the adjustable power factor of the inverter. The unbalance OPF is formulated by current balance equations and solved by primal-dual interior point method. Several simulation cases have been carried out varying the size and location of PV systems and the results show a detailed view of the impact of PV distributed generation on distribution systems.Keywords: distribution system, loss, photovoltaic generation, primal-dual interior point method
Procedia PDF Downloads 3216858 Research on Placement Method of the Magnetic Flux Leakage Sensor Based on Online Detection of the Transformer Winding Deformation
Authors: Wei Zheng, Mao Ji, Zhe Hou, Meng Huang, Bo Qi
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The transformer is the key equipment of the power system. Winding deformation is one of the main transformer defects, and timely and effective detection of the transformer winding deformation can ensure the safe and stable operation of the transformer to the maximum extent. When winding deformation occurs, the size, shape and spatial position of the winding will change, which directly leads to the change of magnetic flux leakage distribution. Therefore, it is promising to study the online detection method of the transformer winding deformation based on magnetic flux leakage characteristics, in which the key step is to study the optimal placement method of magnetic flux leakage sensors inside the transformer. In this paper, a simulation model of the transformer winding deformation is established to obtain the internal magnetic flux leakage distribution of the transformer under normal operation and different winding deformation conditions, and the law of change of magnetic flux leakage distribution due to winding deformation is analyzed. The results show that different winding deformation leads to different characteristics of the magnetic flux leakage distribution. On this basis, an optimized placement of magnetic flux leakage sensors inside the transformer is proposed to provide a basis for the online detection method of transformer winding deformation based on the magnetic flux leakage characteristics.Keywords: magnetic flux leakage, sensor placement method, transformer, winding deformation
Procedia PDF Downloads 1736857 Empirical Study of Running Correlations in Exam Marks: Same Statistical Pattern as Chance
Authors: Weisi Guo
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It is well established that there may be running correlations in sequential exam marks due to students sitting in the order of course registration patterns. As such, a random and non-sequential sampling of exam marks is a standard recommended practice. Here, the paper examines a large number of exam data stretching several years across different modules to see the degree to which it is true. Using the real mark distribution as a generative process, it was found that random simulated data had no more sequential randomness than the real data. That is to say, the running correlations that one often observes are statistically identical to chance. Digging deeper, it was found that some high running correlations have students that indeed share a common course history and make similar mistakes. However, at the statistical scale of a module question, the combined effect is statistically similar to the random shuffling of papers. As such, there may not be the need to take random samples for marks, but it still remains good practice to mark papers in a random sequence to reduce the repetitive marking bias and errors.Keywords: data analysis, empirical study, exams, marking
Procedia PDF Downloads 1656856 Steady State Creep Behavior of Functionally Graded Thick Cylinder
Authors: Tejeet Singh, Harmanjit Singh
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Creep behavior of thick-walled functionally graded cylinder consisting of AlSiC and subjected to internal pressure and high temperature has been analyzed. The functional relationship between strain rate with stress can be described by the well-known threshold stress based creep law with a stress exponent of five. The effect of imposing non-linear particle gradient on the distribution of creep stresses in the thick-walled functionally graded composite cylinder has been investigated. The study revealed that for the assumed non-linear particle distribution, the radial stress decreases throughout the cylinder, whereas the tangential, axial and effective stresses have averaging effect. The strain rates in the functionally graded composite cylinder could be reduced to significant extent by employing non-linear gradient in the distribution of reinforcement.Keywords: functionally graded material, pressure, steady state creep, thick-cylinder
Procedia PDF Downloads 4616855 Availability and Utilization of Health Care Facilities in Jalpaiguri Town
Authors: Sharmistha Mukherjee
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Health care is the basic requirement for all. The prime question is who gets what, where and how? The unequal distribution of basic facilities do have a adverse effect on the users. The paper tries to examine health care in terms of available facilities, the health care need and how people perceive to it in a small town of Jalpaiguri in the midst of tea gardens in North Bengal. The morbidity pattern is also minutely observed with a section describing the organizational structure of health care keeping in mind the utilization.Keywords: availability, distribution, health care, utilization
Procedia PDF Downloads 5076854 A Novel Probablistic Strategy for Modeling Photovoltaic Based Distributed Generators
Authors: Engy A. Mohamed, Y. G. Hegazy
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This paper presents a novel algorithm for modeling photovoltaic based distributed generators for the purpose of optimal planning of distribution networks. The proposed algorithm utilizes sequential Monte Carlo method in order to accurately consider the stochastic nature of photovoltaic based distributed generators. The proposed algorithm is implemented in MATLAB environment and the results obtained are presented and discussed.Keywords: comulative distribution function, distributed generation, Monte Carlo
Procedia PDF Downloads 5656853 Nonlinear Equations with n-Dimensional Telegraph Operator Iterated K-Times
Authors: Jessada Tariboon
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In this article, using distribution kernel, we study the nonlinear equations with n-dimensional telegraph operator iterated k-times.Keywords: telegraph operator, elementary solution, distribution kernel, nonlinear equations
Procedia PDF Downloads 4726852 Workload and Task Distribution in Public Healthcare: A Qualitative Explorative Study From Nurse Leaders’ Perceptions
Authors: Jessica Hemberg, Mikaela Miller
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Unreasonable workload and work-related stress can reduce nurse leaders’ job satisfaction and productivity and can increase absence and burnout. Nurse leaders’ workload in public healthcare settings is relatively unresearched. The aim of this study was to investigate nurse leaders’ perceptions of workload and task distribution with relation to leading work tasks in public healthcare. A qualitative explorative design was used. The data material consisted of texts from interviews with nurse leaders in public healthcare (N=8). The method was inspired by content analysis. The COREQ checklist was used. Informed consent was sought from the participants regarding study participation and the storage and handling of data for research purposes. Six main themes were found: Increased and unreasonable workload, Length of work experience as nurse leader affects perception of workload, Number of staff and staff characteristics affect perception of workload, Versatile and flexible task distribution, Working overtime as a way of managing high workload, and Insufficient time for leadership mission. The workload for nurse leaders in a public healthcare setting was perceived to be unreasonable. Common measures for managing high workload included working overtime, delegating work tasks and organizing more staff resources in the form of additional staff. How nurse leaders perceive their workload was linked to both the number of staff and staff characteristics. These should both be considered equally important when determining staff levels and measuring nurse leaders’ workload. Future research should focus on investigating workload and task distribution from nurses’ perspectives.Keywords: nurse leaders, workload, task distribution, public healthcare, qualitative
Procedia PDF Downloads 856851 Computer Simulation Studies of Spinel LiMn₂O₄ Nanotubes
Authors: D. M. Tshwane, R. R. Maphanga, P. E. Ngoepe
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Nanostructured materials are attractive candidates for efficient electrochemical energy storage devices because of their unique physicochemical properties. Nanotubes have drawn a continuous attention because of their unique electrical, optical and magnetic properties contrast to that of bulk system. They have potential application in the field of optical, electronics and energy storage device. Introducing nanotubes structures as electrode materials; represents one of the most attractive strategies that could dramatically enhance the battery performance. Spinel LiMn2O4 is the most promising cathode material for Li-ion batteries. In this work, computer simulation methods are used to generate and investigate properties of spinel LiMn2O4 nanotubes. Molecular dynamic simulation is used to probe the local structure of LiMn2O4 nanotubes and the effect of temperature on these systems. It is found that diameter, Miller indices and size have a direct control on nanotubes morphology. Furthermore, it is noted that stability depends on surface and wrapping of the nanotube. The nanotube structures are described using the radial distribution function and XRD patterns. There is a correlation between calculated XRD and experimentally reported results.Keywords: LiMn2O4, li-ion batteries, nanotubes, nanostructures
Procedia PDF Downloads 1776850 Determining Best Fitting Distributions for Minimum Flows of Streams in Gediz Basin
Authors: Naci Büyükkaracığan
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Today, the need for water sources is swiftly increasing due to population growth. At the same time, it is known that some regions will face with shortage of water and drought because of the global warming and climate change. In this context, evaluation and analysis of hydrological data such as the observed trends, drought and flood prediction of short term flow has great deal of importance. The most accurate selection probability distribution is important to describe the low flow statistics for the studies related to drought analysis. As in many basins In Turkey, Gediz River basin will be affected enough by the drought and will decrease the amount of used water. The aim of this study is to derive appropriate probability distributions for frequency analysis of annual minimum flows at 6 gauging stations of the Gediz Basin. After applying 10 different probability distributions, six different parameter estimation methods and 3 fitness test, the Pearson 3 distribution and general extreme values distributions were found to give optimal results.Keywords: Gediz Basin, goodness-of-fit tests, minimum flows, probability distribution
Procedia PDF Downloads 2616849 Applying Arima Data Mining Techniques to ERP to Generate Sales Demand Forecasting: A Case Study
Authors: Ghaleb Y. Abbasi, Israa Abu Rumman
Abstract:
This paper modeled sales history archived from 2012 to 2015 bulked in monthly bins for five products for a medical supply company in Jordan. The sales forecasts and extracted consistent patterns in the sales demand history from the Enterprise Resource Planning (ERP) system were used to predict future forecasting and generate sales demand forecasting using time series analysis statistical technique called Auto Regressive Integrated Moving Average (ARIMA). This was used to model and estimate realistic sales demand patterns and predict future forecasting to decide the best models for five products. Analysis revealed that the current replenishment system indicated inventory overstocking.Keywords: ARIMA models, sales demand forecasting, time series, R code
Procedia PDF Downloads 366