Search results for: loading factor performance
12255 Examining the Influence of Organisational Culture on Middle Leadership in Primary Schools in Saudi Arabia and United Kingdom
Authors: Saeed Musaid Alzahrani
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Shared values, beliefs, norms and assumptions within the organisation can affect personal and team effectiveness. Organisational culture can also affect the performance of organisational members. The nature of middle leadership in a primary school is largely influenced by organizational culture. The effectiveness of middle leadership in primary schools and their performance is strongly determined by the circumstances in which they work and can be political or institutional. This study aims to examine the influence of organisational culture and government policy on the performance and effectiveness of middle managers, using the English and Saudi education systems as case studies. To examine how education policy conditions educational discourse, and answer the research questions, there is a need to collect qualitative data on middle manager’s perceptions and experiences in the English and Saudi Arabian contexts. The study involved a qualitative and interpretative approach. In-depth interviews with 6 middle managers and school supervisors in 3 English primary schools and 6 middle managers in 3 Saudi Arabian primary schools were conducted to answer the research questions. The study also included ethnographic tools such as observations of a sample of three primary schools in both England and Saudi Arabia where the researcher observed middle managers’ interactions with their peers. The sample of three enabled the study to identify trends and make comparisons between leadership approaches in both systems based on observations without the bias of prescriptions. The use of ethnographic tools not only makes the study empirical but also increases the reliability and validity of the findings by reducing prescriptive bias. The observations will be triangulated with the results of the interviews to draw comparisons and conclusions on whether middle managers act as leaders or as followers in their respective political contexts.Keywords: education management, government education policies, middle managers, organisational culture
Procedia PDF Downloads 24612254 Parametric Study and Modelling of Orthogonal Cutting Process for AISI 4340 and Ti-6Al-4V Alloy
Authors: Purnank Bhatt, Mit Shah, Pawan Nagda, Vimal Jasoliya
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The influence of parameters like velocity and depth of cut on cutting forces is investigated for the empirical relation of the coefficient of friction derived for CRS 1018 for different materials like AISI 4340 and Ti6Al4V. For this purpose, turning tests were carried out on the above materials using coated cemented carbide tool inserts for steel grade and uncoated cemented carbide cutting tool inserts for Titanium with different chip breaker geometries. The cutting forces were measured using a Kistler dynamometer where the multiplication factor taken is 200.The effect of cutting force variation was analyzed experimentally and are compared with the analytical results.Keywords: cutting forces, coefficient of friction, carbide tool inserts, titanium
Procedia PDF Downloads 37612253 Stock Movement Prediction Using Price Factor and Deep Learning
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The development of machine learning methods and techniques has opened doors for investigation in many areas such as medicines, economics, finance, etc. One active research area involving machine learning is stock market prediction. This research paper tries to consider multiple techniques and methods for stock movement prediction using historical price or price factors. The paper explores the effectiveness of some deep learning frameworks for forecasting stock. Moreover, an architecture (TimeStock) is proposed which takes the representation of time into account apart from the price information itself. Our model achieves a promising result that shows a potential approach for the stock movement prediction problem.Keywords: classification, machine learning, time representation, stock prediction
Procedia PDF Downloads 15112252 Metamorphic Computer Virus Classification Using Hidden Markov Model
Authors: Babak Bashari Rad
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A metamorphic computer virus uses different code transformation techniques to mutate its body in duplicated instances. Characteristics and function of new instances are mostly similar to their parents, but they cannot be easily detected by the majority of antivirus in market, as they depend on string signature-based detection techniques. The purpose of this research is to propose a Hidden Markov Model for classification of metamorphic viruses in executable files. In the proposed solution, portable executable files are inspected to extract the instructions opcodes needed for the examination of code. A Hidden Markov Model trained on portable executable files is employed to classify the metamorphic viruses of the same family. The proposed model is able to generate and recognize common statistical features of mutated code. The model has been evaluated by examining the model on a test data set. The performance of the model has been practically tested and evaluated based on False Positive Rate, Detection Rate and Overall Accuracy. The result showed an acceptable performance with high average of 99.7% Detection Rate.Keywords: malware classification, computer virus classification, metamorphic virus, metamorphic malware, Hidden Markov Model
Procedia PDF Downloads 31812251 Numerical Studies on the Performance of the Finned-Tube Heat Exchanger
Authors: S. P. Praveen Kumar, Bong-Su Sin, Kwon-Hee Lee
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Finned-tube heat exchangers are predominantly used in space conditioning systems, as well as other applications requiring heat exchange between two fluids. The design of finned-tube heat exchangers requires the selection of over a dozen design parameters by the designer such as tube pitch, tube diameter, tube thickness, etc. Finned-tube heat exchangers are common devices; however, their performance characteristics are complicated. In this paper, numerical studies have been carried out to analyze the performances of finned tube heat exchanger (without fins considered for experimental purpose) by predicting the characteristics of temperature difference and pressure drop. In this study, a design considering 5 design variables, maximizing the temperature difference and minimizing the pressure drop was suggested by applying DOE. In this process, L18 orthogonal array was adopted. Parametric analytical studies have been carried out using Analysis of Variance (ANOVA) to determine the relative importance of each variable with respect to the temperature difference and the pressure drop. Following the results, the final design was suggested by predicting the optimum design therefore confirming the optimized condition.Keywords: heat exchanger, fluid analysis, heat transfer, design of experiment, analysis of variance
Procedia PDF Downloads 44912250 Optimization of SWL Algorithms Using Alternative Adder Module in FPGA
Authors: Tayab D. Memon, Shahji Farooque, Marvi Deshi, Imtiaz Hussain Kalwar, B. S. Chowdhry
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Recently single-bit ternary FIR-like filter (SBTFF) hardware synthesize in FPGA is reported and compared with multi-bit FIR filter on similar spectral characteristics. Results shows that SBTFF dominates upon multi-bit filter overall. In this paper, an optimized adder module for ternary quantized sigma-delta modulated signal is presented. The adder is simulated using ModelSim for functional verification the area-performance of the proposed adder were obtained through synthesis in Xilinx and compared to conventional adder trees. The synthesis results show that the proposed adder tree achieves higher clock rates and lower chip area at higher inputs to the adder block; whereas conventional adder tree achieves better performance and lower chip area at lower number of inputs to the same adder block. These results enhance the usefulness of existing short word length DSP algorithms for fast and efficient mobile communication.Keywords: short word length (SWL), DSP algorithms, FPGA, SBTFF, VHDL
Procedia PDF Downloads 34912249 Evaluation and Selection of Contractors in Construction Projects with a View Supply Chain Management and Utilization of Promthee
Authors: Sara Najiazarpour, Mahsa Najiazarpour
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There are many problems in contracting projects and their performance. At each project stage and due to different reasons, these problems affect cost, time and overall project quality. Hence, in order to increase the efficiency and performance in all levels of the chain and with supply chain management approach, there will be a coordination from the beginning of a project (contractor selection) to the end of project (handover of project). Contractor selection is the foremost part of construction projects which in this multi-criteria decision-making, the best contractor is determined by expert judgment, different variables and their priorities. In this paper for selecting the best contractor, numerous criteria were collected by asking from adept experts and then among them, 16 criteria with highest frequency were considered for questionnaire. This questionnaire was distributed between experts. Cronbach's alpha coefficient was obtained as 72%. Then based on Borda's function 12 important criteria was selected which was categorized in four main criteria and related sub-criteria as follow: Environmental factors and physical equipment: procurement and materials (supplier), company's machines, contractor’s proposed cost estimate - financial capacity: bank turnover and company's assets, the income of tax declaration in last year, Ability to compensate for losses or delays - past performance- records and technical expertise: experts and key personnel, the past technical backgrounds and experiences, employer satisfaction of previous contracts, the number of similar projects was done - standards: rank and field of expertise which company is qualified for and its validity, availability and number of permitted projects done. Then with PROMTHEE method, the criteria were normalized and monitored, finally the best alternative was selected. In this research, qualitative criteria of each company is became a quantitative criteria. Finally, information of some companies was evaluated and the best contractor was selected based on all criteria and their priorities.Keywords: contractor evaluation and selection, project development, supply chain management, PROMTHEE method
Procedia PDF Downloads 7612248 Development of Structural Deterioration Models for Flexible Pavement Using Traffic Speed Deflectometer Data
Authors: Sittampalam Manoharan, Gary Chai, Sanaul Chowdhury, Andrew Golding
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The primary objective of this paper is to present a simplified approach to develop the structural deterioration model using traffic speed deflectometer data for flexible pavements. Maintaining assets to meet functional performance is not economical or sustainable in the long terms, and it would end up needing much more investments for road agencies and extra costs for road users. Performance models have to be included for structural and functional predicting capabilities, in order to assess the needs, and the time frame of those needs. As such structural modelling plays a vital role in the prediction of pavement performance. A structural condition is important for the prediction of remaining life and overall health of a road network and also major influence on the valuation of road pavement. Therefore, the structural deterioration model is a critical input into pavement management system for predicting pavement rehabilitation needs accurately. The Traffic Speed Deflectometer (TSD) is a vehicle-mounted Doppler laser system that is capable of continuously measuring the structural bearing capacity of a pavement whilst moving at traffic speeds. The device’s high accuracy, high speed, and continuous deflection profiles are useful for network-level applications such as predicting road rehabilitations needs and remaining structural service life. The methodology adopted in this model by utilizing time series TSD maximum deflection (D0) data in conjunction with rutting, rutting progression, pavement age, subgrade strength and equivalent standard axle (ESA) data. Then, regression analyses were undertaken to establish a correlation equation of structural deterioration as a function of rutting, pavement age, seal age and equivalent standard axle (ESA). This study developed a simple structural deterioration model which will enable to incorporate available TSD structural data in pavement management system for developing network-level pavement investment strategies. Therefore, the available funding can be used effectively to minimize the whole –of- life cost of the road asset and also improve pavement performance. This study will contribute to narrowing the knowledge gap in structural data usage in network level investment analysis and provide a simple methodology to use structural data effectively in investment decision-making process for road agencies to manage aging road assets.Keywords: adjusted structural number (SNP), maximum deflection (D0), equant standard axle (ESA), traffic speed deflectometer (TSD)
Procedia PDF Downloads 15112247 Electrochemical Performance of Femtosecond Laser Structured Commercial Solid Oxide Fuel Cells Electrolyte
Authors: Mohamed A. Baba, Gazy Rodowan, Brigita Abakevičienė, Sigitas Tamulevičius, Bartlomiej Lemieszek, Sebastian Molin, Tomas Tamulevičius
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Solid oxide fuel cells (SOFC) efficiently convert hydrogen to energy without producing any disturbances or contaminants. The core of the cell is electrolyte. For improving the performance of electrolyte-supported cells, it is desirable to extend the available exchange surface area by micro-structuring of the electrolyte with laser-based micromachining. This study investigated the electrochemical performance of cells micro machined using a femtosecond laser. Commercial ceramic SOFC (Elcogen, AS) with a total thickness of 400 μm was structured by 1030 nm wavelength Yb: KGW fs-laser Pharos (Light Conversion) using 100 kHz repetition frequency and 290 fs pulse length light by scanning with the galvanometer scanner (ScanLab) and focused with a f-Theta telecentric lens (SillOptics). The sample height was positioned using a motorized z-stage. The microstructures were formed using a laser spiral trepanning in Ni/YSZ anode supported membrane at the central part of the ceramic piece of 5.5 mm diameter at active area of the cell. All surface was drilled with 275 µm diameter holes spaced by 275 µm. The machining processes were carried out under ambient conditions. The microstructural effects of the femtosecond laser treatment on the electrolyte surface were investigated prior to the electrochemical characterisation using a scanning electron microscope (SEM) Quanta 200 FEG (FEI). The Novo control Alpha-A was used for electrochemical impedance spectroscopy on a symmetrical cell configuration with an excitation amplitude of 25 mV and a frequency range of 1 MHz to 0.1 Hz. The fuel cell characterization of the cell was examined on open flanges test setup by Fiaxell. Using nickel mesh on the anode side and au mesh on the cathode side, the cell was electrically linked. The cell was placed in a Kittec furnace with a Process IDentifier temperature controller. The wires were connected to a Solartron 1260/1287 frequency analyzer for the impedance and current-voltage characterization. In order to determine the impact of the anode's microstructure on the performance of the commercial cells, the acquired results were compared to cells with unstructured anode. Geometrical studies verified that the depth of the -holes increased linearly according to laser energy and scanning times. On the other hand, it reduced as the scanning speed increased. The electrochemical analysis demonstrates that the open circuit voltage OCV values of the two cells are equal. Further, the modified cell's initial slope reduces to 0.209 from 0.253 of the unmodified cell, revealing that the surface modification considerably decreases energy loss. Plus, the maximum power density for the cell with the microstructure and the reference cell respectively, are 1.45 and 1.16 Wcm⁻².Keywords: electrochemical performance, electrolyte-supported cells, laser micro-structuring, solid oxide fuel cells
Procedia PDF Downloads 7312246 Applying Big Data Analysis to Efficiently Exploit the Vast Unconventional Tight Oil Reserves
Authors: Shengnan Chen, Shuhua Wang
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Successful production of hydrocarbon from unconventional tight oil reserves has changed the energy landscape in North America. The oil contained within these reservoirs typically will not flow to the wellbore at economic rates without assistance from advanced horizontal well and multi-stage hydraulic fracturing. Efficient and economic development of these reserves is a priority of society, government, and industry, especially under the current low oil prices. Meanwhile, society needs technological and process innovations to enhance oil recovery while concurrently reducing environmental impacts. Recently, big data analysis and artificial intelligence become very popular, developing data-driven insights for better designs and decisions in various engineering disciplines. However, the application of data mining in petroleum engineering is still in its infancy. The objective of this research aims to apply intelligent data analysis and data-driven models to exploit unconventional oil reserves both efficiently and economically. More specifically, a comprehensive database including the reservoir geological data, reservoir geophysical data, well completion data and production data for thousands of wells is firstly established to discover the valuable insights and knowledge related to tight oil reserves development. Several data analysis methods are introduced to analysis such a huge dataset. For example, K-means clustering is used to partition all observations into clusters; principle component analysis is applied to emphasize the variation and bring out strong patterns in the dataset, making the big data easy to explore and visualize; exploratory factor analysis (EFA) is used to identify the complex interrelationships between well completion data and well production data. Different data mining techniques, such as artificial neural network, fuzzy logic, and machine learning technique are then summarized, and appropriate ones are selected to analyze the database based on the prediction accuracy, model robustness, and reproducibility. Advanced knowledge and patterned are finally recognized and integrated into a modified self-adaptive differential evolution optimization workflow to enhance the oil recovery and maximize the net present value (NPV) of the unconventional oil resources. This research will advance the knowledge in the development of unconventional oil reserves and bridge the gap between the big data and performance optimizations in these formations. The newly developed data-driven optimization workflow is a powerful approach to guide field operation, which leads to better designs, higher oil recovery and economic return of future wells in the unconventional oil reserves.Keywords: big data, artificial intelligence, enhance oil recovery, unconventional oil reserves
Procedia PDF Downloads 28712245 Heat Transfer Enhancement Using Aluminium Oxide Nanofluid: Effect of the Base Fluid
Authors: M. Amoura, M. Benmoussa, N. Zeraibi
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The flow and heat transfer is an important phenomenon in engineering systems due to its wide application in electronic cooling, heat exchangers, double pane windows etc.. The enhancement of heat transfer in these systems is an essential topic from an energy saving perspective. Lower heat transfer performance when conventional fluids, such as water, engine oil and ethylene glycol are used hinders improvements in performance and causes a consequent reduction in the size of such systems. The use of solid particles as an additive suspended into the base fluid is a technique for heat transfer enhancement. Therefore, the heat transfer enhancement in a horizontal circular tube that is maintained at a constant temperature under laminar regime has been investigated numerically. A computational code applied to the problem by use of the finite volume method was developed. Nanofluid was made by dispersion of Al2O3 nanoparticles in pure water and ethylene glycol. Results illustrate that the suspended nanoparticles increase the heat transfer with an increase in the nanoparticles volume fraction and for a considered range of Reynolds numbers. On the other hand, the heat transfer is very sensitive to the base fluid.Keywords: Al2O3 nanoparticles, circular tube, heat transfert enhancement, numerical simulation
Procedia PDF Downloads 32812244 Internal Power Recovery in Cryogenic Cooling Plants, Part II: Compressor Development
Authors: Ambra Giovannelli, Erika Maria Archilei
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The electrical power consumption related to refrigeration systems is evaluated to be in the order of 15% of the total electricity consumption worldwide. For this reason, in the last years several energy saving techniques have been suggested to reduce the power demand of refrigeration and air conditioning plants. The research work deals with the development of an innovative internal power recovery system for industrial cryogenic cooling plants. Such system is based on a Compressor-Expander Group (CEG). Both the expander and the compressor have been designed starting from automotive turbocharging components, strongly modified to take refrigerant fluid properties and specific system requirements into consideration. A preliminary choice of the machines (radial compressors and expanders) among existing components available on the market was realised according to the rules of the similarity theory. Once the expander was selected, it was strongly modified and performance verified by means of steady-state 3D CFD simulations. This paper focuses the attention on the development of the second CEG main component: the compressor. Once the preliminary selection has been done, the compressor geometry has been modified to take the new boundary conditions into account. In particular, the impeller has been machined to address the required total enthalpy increase. Such evaluation has been carried out by means of a simplified 1D model. Moreover, a vaneless diffuser has been added, modifying the shape of casing rear and front disks. To verify the performance of the modified compressor geometry and suggest improvements, a numerical fluid dynamic model has been set up and the commercial Ansys-CFX software has been used to perform steady-state 3D simulations. In this work, all the numerical results will be shown, highlighting critical aspects and suggesting further developments to increase compressor performance and flexibility.Keywords: vapour compression systems, energy saving, refrigeration plant, organic fluids, centrifugal compressor
Procedia PDF Downloads 22012243 The Effects of Arginine, Glutamine and Threonine Supplementation in the Starting Phase on Subsequent Performance of Male Broile
Authors: Jalal Fazli Amiri, Mohammad Hossein Shahir, Mohammad Hossein Nemati, Afshin Heidarinia
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The current study was performed to investigate the effects of arginine, threonine, and glutamine supplementation in excess of requirements in the starter period (17 days) on performance, intestinal morphology, and immune response of broilers. Four hundred and sixteen male day-old chicks were assigned in a 2×2×2 factorial arrangement to a completely randomized design with four replicates (13 birds per replicate ). Treatments were: a control group that received the basal diet, basal diet plus 1% glutamine, basal diet plus 0.2% threonine, basal diet plus 0.75 % arginine, and combination of these three amino acids (glutamine+arginine, glutamine+threonine, arginine+threonine and arginine+ glutamine+threonine). The effect of glutamine supplementation on feed intake was significant in week 4 (p < 0.05), week 6 (p < 0.001), and total feed intake (p < 0.05) and caused declined feed intake. No significant differences of glutamine addition were observed on intestinal morphology (villi height, crypt depth, villi height to crypt depth ratio, villi width). Threonine supplementation caused increased weight gain in week 2 (p < 0.001) and 3 and a decrease of total feed intake (p < 0.05). Duodenum and jejunum villi height, crypt depth, villi height to crypt depth ratio, villi width were not affected. The effect of arginine supplementation was the increase of breast percentage (p < 0.05) and a decrease of jejunum villi high (p < 0.05) and Jejunum crypt depth (p < 0.05). Supplementation of arginine, threonine, and glutamine had no significant effects on blood titer of antibodies against Newcastle disease, infectious bronchitis, avian influenza. Overall, it seems that the supplementation of arginine, threonine, and glutamine in excess of requirements in the starter period had no effect on performance in subsequent periods and intestinal morphology.Keywords: intestinal morphology, immunity, broiler chickens, glutamine, arginine, threonine
Procedia PDF Downloads 14012242 Hydraulic Performance of Urban Drainage System Using SWMM: A Case Study of Siti Khadijah Retention Pond in Palembang City
Authors: Muhammad B. Al Amin, Nyimas S. Rika, Dwi F. Yanto, Marcelina
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Siti Khadijah retention pond is located beside of Siti Khadijah Islamic Hospital on Demang Lebar Daun Street in Palembang City. This retention pond is functioned as storage for runoff from drainage channels in the surrounding area before entering Sekanak River, which is one of Musi River tributaries. However, in recent years, the developments in the surrounding area into paved area trigger to increase runoff discharge that causes the pond can no longer store it adequately. This study aimed to investigate the hydraulic performance of drainage system in the area around Siti Khadijah retention pond. A SWMM model was used to simulate runoff discharge into the pond and out from the pond, so the water level fluctuation within the pond and its capacity could be determined. Besides that, the water depth within drainage channels was simulated as well. The results showed that capacity of retention pond and some drainage channels already inadequate, so the area around it potentially to be flooded. Thus, it is necessary to increase the capacity of the retention pond and drainage channels.Keywords: flood, retention pond, SWMM, urban drainage system
Procedia PDF Downloads 44712241 Impact of Solar Radiation Effects on the Physicochemical Properties of Unformulated Polyethylene (PE) Plastic Film
Authors: A. Adelhafidhi, I. M. Babaghayou, S. F. Chabira, M. Sebaa
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This study deals with the photodegradation of unformulated polyethylene films for greenhouse covering. The UV range of solar light appears as the most deleterious factor of plastic degradation in outdoor exposure. The reasons of this photosensitivity are structural defects which are light-absorbing. The use of FTIR as an investigation tool has revealed that the material reacts with surrounding oxygen via a photooxidation process. Although the photochemical process is quite complex, it appears through this study than crosslinking and chain scissions are the most important events taking place during aging These two key reactions change irremediably the average molecular weight affecting thus drastically the mechanical properties and reducing, in the same way, the service lifetime of the films.Keywords: polyethylene, films, unformulated, FTIR, ageing
Procedia PDF Downloads 37312240 Electrode Performance of Carbon Coated Nanograined LiFePO4 in Lithium Batteries
Authors: Princess Stephanie P. Llanos, Rinlee Butch M. Cervera
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Lithium iron phosphate (LiFePO4) is a potential cathode material for lithium-ion batteries due to its promising characteristics. In this study, carbon-coated nanograined LiFePO4 is synthesized via wet chemistry method at a low temperature of 400 °C and investigated its performance as a cathode in Lithium battery. The X-ray diffraction pattern of the synthesized samples can be indexed to an orthorhombic LiFePO4 structure. Agglomerated particles that range from 200 nm to 300 nm are observed from scanning electron microscopy images. Transmission electron microscopy images confirm the crystalline structure of LiFePO4 and coating of amorphous carbon layer. Elemental mapping using Energy dispersive spectroscopy analysis revealed the homogeneous dispersion of Fe, P, O, and C elements. On the other hand, the electrochemical performances of the synthesized cathodes were investigated using cyclic voltammetry, galvanostatic charge/discharge tests with different C-rates, and cycling performances. Galvanostatic charge and discharge measurements revealed that the sample sintered at 400 °C for 3 hours with carbon coating demonstrated the highest capacity among the samples which reaches up to 160 mAhg⁻¹ at 0.1C rate.Keywords: cathode, charge-discharge, electrochemical, lithium batteries
Procedia PDF Downloads 33312239 A Study on User Authentication Method Using Haptic Actuator and Security Evaluation
Authors: Yo Han Choi, Hee Suk Seo, Seung Hwan Ju, Sung Hyu Han
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As currently various portable devices were launched, smart business conducted using them became common. Since smart business can use company-internal resources in an external remote place, user authentication that can identify authentic users is an important factor. Commonly used user authentication is a method of using user ID and Password. In the user authentication using ID and Password, the user should see and enter authentication information him or herself. In this user authentication system depending on the user’s vision, there is the threat of password leaks through snooping in the process which the user enters his or her authentication information. This study designed and produced a user authentication module using an actuator to respond to the snooping threat.Keywords: actuator, user authentication, security evaluation, haptic actuator
Procedia PDF Downloads 35312238 A Polynomial Approach for a Graphical-based Integrated Production and Transport Scheduling with Capacity Restrictions
Authors: M. Ndeley
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The performance of global manufacturing supply chains depends on the interaction of production and transport processes. Currently, the scheduling of these processes is done separately without considering mutual requirements, which leads to no optimal solutions. An integrated scheduling of both processes enables the improvement of supply chain performance. The integrated production and transport scheduling problem (PTSP) is NP-hard, so that heuristic methods are necessary to efficiently solve large problem instances as in the case of global manufacturing supply chains. This paper presents a heuristic scheduling approach which handles the integration of flexible production processes with intermodal transport, incorporating flexible land transport. The method is based on a graph that allows a reformulation of the PTSP as a shortest path problem for each job, which can be solved in polynomial time. The proposed method is applied to a supply chain scenario with a manufacturing facility in South Africa and shipments of finished product to customers within the Country. The obtained results show that the approach is suitable for the scheduling of large-scale problems and can be flexibly adapted to different scenarios.Keywords: production and transport scheduling problem, graph based scheduling, integrated scheduling
Procedia PDF Downloads 47812237 Online Compressor Washing for Gas Turbine Power Output
Authors: Enyia James Diwa, Isaiah Thank-God Ebi, Dodeye Ina Igbong
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The privatization of utilities has brought about very strong competition in industries such as petrochemical and gas distribution among others, considering the continuous increase in cost of fuel. This has brought about the intense reason for gas turbine owners and operators to reduce and control performance degradation of the engine in other to minimize cost. The most common and very crucial problem of the gas turbine is the fouling of compressor, which is mostly caused by a reduction in flow capacity, compressor efficiency, and pressure ratio, this, in turn, lead to the engine compressor re-matching and output power and thermal efficiency reduction. The content of this paper encompasses a detailed presentation of the major causes, effects and control mechanism of fouling. The major emphasis is on compressor water washing to enable power augmentation. A modelled gas turbine similar to that of GE LM6000 is modelled for the current study, based on TURBOMATCH which is a Cranfield University software specifically made for gas turbine performance simulation and fouling detection. The compounded and intricate challenges of compressor online water washing of large output gas turbine are carried out. The treatment is applied to axial compressor used in the petrochemical and hydrocarbon industry.Keywords: gas turbine, fouling, degradation, compressor washing
Procedia PDF Downloads 35212236 An Intelligent Traffic Management System Based on the WiFi and Bluetooth Sensing
Authors: Hamed Hossein Afshari, Shahrzad Jalali, Amir Hossein Ghods, Bijan Raahemi
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This paper introduces an automated clustering solution that applies to WiFi/Bluetooth sensing data and is later used for traffic management applications. The paper initially summarizes a number of clustering approaches and thereafter shows their performance for noise removal. In this context, clustering is used to recognize WiFi and Bluetooth MAC addresses that belong to passengers traveling by a public urban transit bus. The main objective is to build an intelligent system that automatically filters out MAC addresses that belong to persons located outside the bus for different routes in the city of Ottawa. The proposed intelligent system alleviates the need for defining restrictive thresholds that however reduces the accuracy as well as the range of applicability of the solution for different routes. This paper moreover discusses the performance benefits of the presented clustering approaches in terms of the accuracy, time and space complexity, and the ease of use. Note that results of clustering can further be used for the purpose of the origin-destination estimation of individual passengers, predicting the traffic load, and intelligent management of urban bus schedules.Keywords: WiFi-Bluetooth sensing, cluster analysis, artificial intelligence, traffic management
Procedia PDF Downloads 24512235 Politico-Religious Connections to the January 6th Insurrection
Authors: Kirk Johnson, Gabriel Rubin
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The January 6th Insurrection on the United States Capitol Building has been one of the most disturbing expressions of violence in American history. While there are numerous reasons that led to such aggression, there are destructive politico-religious ideologies and understandings, known as Christian Nationalism, White Christian Nationalism, and Christian Dominionism that influenced the actions of the January 6th insurrectionists. Such ideas are deeply rooted in the unification of church and state, a theocracy, embedded within the understanding that Biblical scripture is the blueprint on which the functioning of the American government should follow. In addition, the concept of racial hierarchy is embedded in politico-religious principles of White Christian Nationalism. This paper will examine how Christian Dominionism is one factor that influenced the January 6th Insurrection.Keywords: January 6th insurrection, dominionism, Christian nationalism, polygenism
Procedia PDF Downloads 8312234 Separation of CO2 Using MFI-Alumina Nanocomposite Hollow Fiber Ion-Exchanged with Alkali Metal Cation
Authors: A. Alshebani, Y. Swesi, S. Mrayed, F. Altaher, I. Musbah
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Cs-type nanocomposite zeolite membrane was successfully synthesized on an alumina ceramic hollow fibre with a mean outer diameter of 1.7 mm; cesium cationic exchange test was carried out inside test module with mean wall thickness of 230 μm and an average crossing pore size smaller than 0.2 μm. Separation factor of n-butane/H2 obtained indicate that a relatively high quality closed to 20. Maxwell-Stefan modeling provides an equivalent thickness lower than 1 µm. To compare the difference an application to CO2/N2 separation has been achieved, reaching separation factors close to (4,18) before and after cation exchange on H-zeolite membrane formed within the pores of a ceramic alumina substrate.Keywords: MFI membrane, nanocomposite, ceramic hollow fibre, CO2, ion-exchange
Procedia PDF Downloads 30112233 The Relationship of Lean Management Principles with Lean Maturity Levels: Multiple Case Study in Manufacturing Companies
Authors: Alexandre D. Ferraz, Dario H. Alliprandini, Mauro Sampaio
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Companies and other institutions are constantly seeking better organizational performance and greater competitiveness. In order to fulfill this purpose, there are many tools, methodologies and models for increasing performance. However, the Lean Management approach seems to be the most effective in terms of achieving a significant improvement in productivity relatively quickly. Although Lean tools are relatively easy to understand and implement in different contexts, many organizations are not able to transform themselves into 'Lean companies'. Most of the efforts in its implementation have shown single benefits, failing to achieve the desired impact on the performance of the overall enterprise system. There is also a growing perception of the importance of management in Lean transformation, but few studies have empirically investigated and described the 'Lean Management'. In order to understand more clearly the ideas that guide Lean Management and its influence on the maturity level of the production system, the objective of this research is analyze the relationship between the Lean Management principles and the Lean maturity level in the organizations. The research also analyzes the principles of Lean Management and its relationship with the 'Lean culture' and the results obtained. The research was developed using the case study methodology. Three manufacturing units of a German multinational company from industrial automation segment, located in different countries were studied, in order to have a better comparison between the practices and the level of maturity in the implementation. The primary source of information was the application of a research questionnaire based on the theoretical review. The research showed that higher the level of Lean Management principles, higher are the Lean maturity level, the Lean culture level, and the level of Lean results obtained in the organization. The research also showed that factors such as time for application of Lean concepts and company size were not determinant for the level of Lean Management principles and, consequently, for the level of Lean maturity in the organization. The characteristics of the production system showed much more influence in different evaluated aspects. The present research also left recommendations for the managers of the plants analyzed and suggestions for future research.Keywords: lean management, lean principles, lean maturity level, lean manufacturing
Procedia PDF Downloads 15112232 Performance Evaluation of Vermiculite as Adsorbent Material for Solar-Assisted Air-Conditioning in Tropical Climate
Authors: Norhayati Mat Wajid, Abdul Murad Zainal Abidin, Hasila Jarimi, Kamaruzaman Sopian, Adnan Ibrahim, Ahmad Fazlizan, Afif Safwan
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Solar-adsorption air-conditioning system (SADCS) is an alternative to the conventional vapor compression system (VCS). SADCS have advantages over VCS system, such as 1) a green cooling technology which utilizes solar energy to drive the adsorption/desorption cycle, 2) can be operated using green refrigerant HFC free pure water, 3) mechanically simpler, and 4) lower operating noise level since it has no moving parts other than the magnetic valves. Several advancements have been achieved in these fields in the last decade, but further research is still needed to escalate this technology to a practical level. Hence, this paper presents a literature survey and a review that add insights into the current state-of-the-art of SADCS technologies with emphasis on the practical researches that were conducted at the laboratory scale and commercial level. In this paper, the performance evaluation of vermiculite as adsorbent material for SADCS in tropical climate discussed in comparison to other adsorbent material such as silica gel.Keywords: adsorption cooling, solar-assisted cooling, HVAC, tropical climate, solar thermal
Procedia PDF Downloads 15712231 Theorizing Women’s Political Leadership: Cross-National Comparison
Authors: Minjeoung Kim
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Since women obtained the right to vote in 1893 for the first time in New Zealand, they have tried to participate actively into politics but still the world has a few women in political leadership. The article asks which factors might influence the appearance of women leadership in politics. The article investigates two factors such as political context, personal factors. Countries where economic development is stable and political democracy is consolidated have a tendency of appearance of women political leadership but in less developed and politically unstable countries, women politicians can be in power with their own reasons. For the personal factor, their feminist propensity is studied but there is no relationship between the appearance of women leaders and their feminist propensity.Keywords: women political leadership, political context, slow track, transitory countries, feminist propensity
Procedia PDF Downloads 41512230 Combined Effect of Roughness and Suction on Heat Transfer in a Laminar Channel Flow
Authors: Marzieh Khezerloo, Lyazid Djenidi
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Owing to wide range of the micro-device applications, the problems of mixing at small scales is of significant interest. Also, because most of the processes produce heat, it is needed to develop and implement strategies for heat removal in these devices. There are many studies which focus on the effect of roughness or suction on heat transfer performance, separately, although it would be useful to take advantage of these two methods to improve heat transfer performance. Unfortunately, there is a gap in this area. The present numerical study is carried to investigate the combined effects of roughness and wall suction on heat transfer performance of a laminar channel flow; suction is applied on the top and back faces of the roughness element, respectively. The study is carried out for different Reynolds numbers, different suction rates, and various locations of suction area on the roughness. The flow is assumed two dimensional, incompressible, laminar, and steady state. The governing Navier-Stokes equations are solved using ANSYS-Fluent 18.2 software. The present results are tested against previous theoretical results. The results show that by adding suction, the local Nusselt number is enhanced in the channel. In addition, it is shown that by applying suction on the bottom section of the roughness back face, one can reduce the thickness of thermal boundary layer, which leads to an increase in local Nusselt number. This indicates that suction is an effective means for improving the heat transfer rate (suction by controls the thickness of thermal boundary layer). It is also shown that the size and intensity of vortical motion behind the roughness element, decreased with an increasing suction rate, which leads to higher local Nusselt number. So, it can be concluded that by using suction, strategically located on the roughness element, one can control both the recirculation region and the heat transfer rate. Further results will be presented at the conference for coefficient of drag and the effect of adding more roughness elements.Keywords: heat transfer, laminar flow, numerical simulation, roughness, suction
Procedia PDF Downloads 12112229 Performance of the Cmip5 Models in Simulation of the Present and Future Precipitation over the Lake Victoria Basin
Authors: M. A. Wanzala, L. A. Ogallo, F. J. Opijah, J. N. Mutemi
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The usefulness and limitations in climate information are due to uncertainty inherent in the climate system. For any given region to have sustainable development it is important to apply climate information into its socio-economic strategic plans. The overall objective of the study was to assess the performance of the Coupled Model Inter-comparison Project (CMIP5) over the Lake Victoria Basin. The datasets used included the observed point station data, gridded rainfall data from Climate Research Unit (CRU) and hindcast data from eight CMIP5. The methodology included trend analysis, spatial analysis, correlation analysis, Principal Component Analysis (PCA) regression analysis, and categorical statistical skill score. Analysis of the trends in the observed rainfall records indicated an increase in rainfall variability both in space and time for all the seasons. The spatial patterns of the individual models output from the models of MPI, MIROC, EC-EARTH and CNRM were closest to the observed rainfall patterns.Keywords: categorical statistics, coupled model inter-comparison project, principal component analysis, statistical downscaling
Procedia PDF Downloads 37212228 Effect of Core Stability Exercises on Balance between Trunk Muscles in Healthy Adult Subjects
Authors: Amir A. Beltagi, Ahmed R. Abdelbaki
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Background: Core stability training has recently attracted attention for optimizing performance and improving muscle balance for healthy and unhealthy individuals. The purpose of this study was to investigate the effect of beginner’s core stability exercises on the trunk flexors’/extensors’ peak torque ratio and trunk flexors’ and extensors’ peak torques. Methods: Thirty five healthy individuals, randomly assigned into two groups; experimental (group I) and control (group II), participated in the study. Group I involved 20 participants (10 male & 10 female) with mean ±SD age, weight, and height of 20.7±2.4 years, 66.5±12.1 kg and 166.7±7.8 cm respectively. Group II involved 15 participants (6 male & 9 female) with mean ±SD age, weight, and height of 20.3±0.61 years, 68.57±12.2 kg and 164.28 ±7.59 cm respectively. Data were collected using the Biodex Isokinetic system. The participants were tested twice; before and after a 6-week period during which the experimental group performed a core stability training program. Findings: Statistical analysis using the 2x2 Mixed Design ANOVA revealed that there were no significant differences in the trunk flexors’/extensors’ peak torque ratio between the ‘pre’ and ‘post’ tests for either group (p > 0.025). Moreover, there were no significant differences in the trunk flexors’/extensors’ ratios between both groups at either test (p > 0.025). Meanwhile, the 2x2 Mixed Design MANOVA revealed that there were significant differences in the trunk flexors’ and extensors’ peak torques between the ‘pre’ and ‘post’ tests for group I (p < 0.025), while there were no significant differences inbetween for group II (p > 0.025). Moreover, there were no significant differences between both groups for the tested muscles’ peak torques at either test except for that of the trunk flexors at the ‘post’ test only (p < 0.025). Interpretation: The improvement in muscle performance indicated by the increase in the trunk flexors’ and extensors’ peak torques in the experimental group recommends including core stability training in the exercise programs that aim to improve muscle performance.Keywords: core stability, isokinetic, trunk muscles, muscle balance
Procedia PDF Downloads 31612227 Biaxial Fatigue Specimen Design and Testing Rig Development
Authors: Ahmed H. Elkholy
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An elastic analysis is developed to obtain the distribution of stresses, strains, bending moment and deformation for a thin hollow, variable thickness cylindrical specimen when subjected to different biaxial loadings. The specimen was subjected to a combination of internal pressure, axial tensile loading and external pressure. Several axial to circumferential stress ratios were investigated in detail. The analytical model was then validated using experimental results obtained from a test rig using several biaxial loadings. Based on the preliminary results obtained, the specimen was then modified geometrically to ensure uniform strain distribution through its wall thickness and along its gauge length. The new design of the specimen has a higher buckling strength and a maximum value of equivalent stress according to the maximum distortion energy theory. A cyclic function generator of the standard servo-controlled, electro-hydraulic testing machine is used to generate a specific signal shape (sine, square,…) at a certain frequency. The two independent controllers of the electronic circuit cause an independent movement to each servo-valve piston. The movement of each piston pressurizes the upper and lower sides of the actuators alternately. So, the specimen will be subjected to axial and diametral loads independent of each other. The hydraulic system has two different pressures: one pressure will be responsible for axial stress produced in the specimen and the other will be responsible for the tangential stress. Changing the two pressure ratios will change the stress ratios accordingly. The only restriction on the maximum stress obtained is the capacity of the testing system and specimen instability due to buckling.Keywords: biaxial, fatigue, stress, testing
Procedia PDF Downloads 13312226 Application of Metarhizium anisopliae against Meloidogyne javanica in Soil Amended with Oak Debris
Authors: Mohammad Abdollahi
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Tomato (Lycopersicon esculentum Mill.) is one of the most popular, widely grown and the second most important vegetable crop, after potatoes. Nematodes have been identified as one of the major pests affecting tomato production throughout the world. The most destructive nematodes are the genus Meloidogyne. Most widespread and devastating species of this genus are M. incognita, M. javanica, and M. arenaria. These species can cause complete crop loss under adverse growing conditions. There are several potential methods for management of the root knot nematodes. Although the chemicals are widely used against the phytonematodes, because of hazardous effects of these compounds on non-target organisms and on the environment, there is a need to develop other control strategies. Nowadays, non-chemical measures are widely used to control the plant parasitic nematodes. Biocontrol of phytonematodes is an important method among environment-friendly measures of nematode management. There are some soil-inhabiting fungi that have biocontrol potential on phytonematodes, which can be used in nematode management program. The fungus Metarhizium anisopliae, originally is an entomopathogenic bioagent. Biocontrol potential of this fungus on some phytonematodes has been reported earlier. Recently, use of organic soil amendments as well as the use of bioagents is under special attention in sustainable agriculture. This research aimed to reduce the pesticide use in control of root-knot nematode, Meloidogyne javanica in tomato. The effects of M. anisopliae IMI 330189 and different levels of oak tree debris on M. javanica were determined. The combination effect of the fungus as well as the different rates of soil amendments was determined. Pots were filled with steam pasteurized soil mixture and the six leaf tomato seedlings were inoculated with 3000 second stage larvae of M. javanica/kg of soil. After eight weeks, plant growth parameters and nematode reproduction factors were compared. Based on the results of our experiment, combination of M. anisopliae IMI 330189 and oak debris caused more than 90% reduction in reproduction factor of nematode, at the rates of 100 and 150 g/kg soil (P ≤ 0.05). As compared to control, the reduction in number of galls was 76%. It was 86% for nematode reproduction factor, showing the significance of combined effect of both tested agents. Our results showed that plant debris can increase the biological activity of the tested bioagent. It was also proved that there was no adverse effect of oak debris, which potentially has antimicrobial activity, on antagonistic power of applied bioagent.Keywords: biological control, nematode management, organic soil, Quercus branti, root knot nematode, soil amendment
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