Search results for: FuzzyLinear State Estimator (FLSE) and Measurements Uncertainty.

Authors: Kamran Yousefpour, Mojtaba Rostaghi-Chalaki, Jason Warden, David Wallace, Chanyeop Park

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There has been a rising trend in using impulse current generators to investigate the lightning strike protection of materials including aluminum and composites in structures such as wind turbine blade and aircraft body. The focus of this research is to present an impulse current generator built in the High Voltage Lab at Mississippi State University. The generator is capable of producing component A and D of the natural lightning discharges in accordance with the Society of Automotive Engineers (SAE) standard, which is widely used in the aerospace industry. The generator can supply lightning impulse energy up to 400 kJ with the capability of producing impulse currents with magnitudes greater than 200 kA. The electrical circuit and physical components of an improved impulse current generator are described and several lightning strike waveforms with different amplitudes is presented for comparing with the standard waveform. The results of this study contribute to the fundamental understanding the functionality of the impulse current generators and present an impulse current generator developed at the High Voltage Lab of Mississippi State University.

Keywords: impulse current generator, lightning, society of automotive engineers, capacitor

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Authors: Loralee P. Potter, Peter J. Schubert

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Solid-state hydrogen storage using catalytically-modified porous silicon can be rapidly charged at moderate pressures (8 bar) without exothermic runaway. Discharge requires temperatures of approximately 110oC, so for larger storage vessels a means is required for thermal energy to penetrate bulk storage media. This can be realized with low-density metal foams, such as Celmet™. This study explores several material and dimensional choices of the metal foam to produce rapid heating of bulk silicon particulates. Experiments run under vacuum and in a pressurized hydrogen environment bracket conditions of empty and full hydrogen storage vessels, respectively. Curve-fitting of the heating profiles at various distances from an external heat source is used to derive both a time delay and a characteristic time constant. System performance metrics of a hydrogen storage subsystem are derived from the experimental results. A techno-economic analysis of the silicon and metal foam provides comparison with other methods of storing hydrogen for mobile and portable applications. 

Keywords: conduction, convection, kinetics, fuel cell

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Authors: Sukrit Ghorai

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Proof of controlling crack width is a basic condition for securing suitable performance in serviceability limit state. The cracking in concrete can occur at any time from the casting of time to the years after the concrete has been set in place. Most codes struggle with offering procedure for crack width calculation. There is lack in availability of design charts for designers to compute crack width with ease. The focus of the study is to utilize design charts and parametric equations in calculating crack width with minimum error. The paper contains a simplified procedure to calculate crack width for reinforced concrete (RC) sections subjected to bending with axial tensile force following the guidelines of Euro code [DS EN-1992-1-1 & DS EN-1992-1-2]. Numerical examples demonstrate the application of the suggested procedure. Comparison with parallel analytical tools supports the validity of result and show the percentage deviation of crack width in both the procedures. The technique is simple, user friendly and ready to evolve for a greater spectrum of section sizes and materials.

Keywords: Concrete structures, crack width calculation, serviceability limit state, structural design, bridge engineering.

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Authors: K. Arroudj, M. Lanez, M. N. Oudjit

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The introduction of siliceous mineral additions in cement production allows, in addition to the ecological and economic gain, improvement of concrete performance. This improvement is mainly due to the fixing of Portlandite, released during the hydration of cement, by fine siliceous, forming denser calcium silicate hydrates and therefore a more compact cementitious matrix. This research is part of the valuation of the Dune Sand (DS) in the cement industry in Algeria. The high silica content of DS motivated us to study its effect, at ground state, on the properties of mortars in fresh and hardened state. For this purpose, cement pastes and mortars based on ground dune sand (fine quartz) has been analyzed with a replacement to cement of 15%, 20% and 25%. This substitution has reduced the amount of heat of hydration and avoids any risk of initial cracking. In addition, the grinding of the dune sand provides amorphous thin populations adsorbed at the surface of the crystal particles of quartz. Which gives to ground quartz pozzolanic character. This character results an improvement of mechanical strength of mortar (66 MPa in the presence of 25% of ground quartz).

Keywords: Mineralogical structure, Pozzolanic reactivity, quartz, mechanical strength.

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Authors: Do Hoai Nam, Keiko Udo, Akira Mano

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This paper presents the combination of different precipitation data sets and the distributed hydrological model, in order to examine the flood runoff reproductivity of scattered observation catchments. The precipitation data sets were obtained from observation using rain-gages, satellite based estimate (TRMM), and numerical weather prediction model (NWP), then were coupled with the super tank model. The case study was conducted in three basins (small, medium, and large size) located in Central Vietnam. Calculated hydrographs based on ground observation rainfall showed best fit to measured stream flow, while those obtained from TRMM and NWP showed high uncertainty of peak discharges. However, calculated hydrographs using the adjusted rainfield depicted a promising alternative for the application of TRMM and NWP in flood modeling for scattered observation catchments, especially for the extension of forecast lead time.

Keywords: Flood forecast, rainfall-runoff model, satellite rainfall estimate, numerical weather prediction, quantitative precipitation forecasting.

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Authors: Muhammad Rizwan Azhar, Emadadeen Ali

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In this paper, periodic force operation of a wastewater treatment process has been studied for the improved process performance. A previously developed dynamic model for the process is used to conduct the performance analysis. The static version of the model was utilized first to determine the optimal productivity conditions for the process. Then, feed flow rate in terms of dilution rate i.e. (D) is transformed into sinusoidal function. Nonlinear model predictive control algorithm is utilized to regulate the amplitude and period of the sinusoidal function. The parameters of the feed cyclic functions are determined which resulted in improved productivity than the optimal productivity under steady state conditions. The improvement in productivity is found to be marginal and is satisfactory in substrate conversion compared to that of the optimal condition and to the steady state condition, which corresponds to the average value of the periodic function. Successful results were also obtained in the presence of modeling errors and external disturbances.

Keywords: Dilution rate, nonlinear model predictive control, sinusoidal function, wastewater treatment.

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Authors: Cédric Damour, Michel Benne, Brigitte Grondin-Perez, Jean-Pierre Chabriat

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Monitoring and control of cane sugar crystallization processes depend on the stability of the supersaturation (σ ) state. The most widely used information to represent σ is the electrical conductivity κ of the solutions. Nevertheless, previous studies point out the shortcomings of this approach: κ may be regarded as inappropriate to guarantee an accurate estimation of σ in impure solutions. To improve the process control efficiency, additional information is necessary. The mass of crystals in the solution ( c m ) and the solubility (mass ratio of sugar to water / s w m m ) are relevant to complete information. Indeed, c m inherently contains information about the mass balance and / s w m m contains information about the supersaturation state of the solution. The main problem is that c m and / s w m m are not available on-line. In this paper, a model based soft-sensor is presented for a final crystallization stage (C sugar). Simulation results obtained on industrial data show the reliability of this approach, c m and the crystal content ( cc ) being estimated with a sufficient accuracy for achieving on-line monitoring in industry

Keywords: Soft-sensor, on-line monitoring, cane sugarcrystallization.

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Authors: K. Ramash Kumar, S. Jeevananthan

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The Object of this paper is to design and analyze a Hysteresis modulation based sliding mode control (HMSMC) for positive output elementary super lift Luo converter (POESLLC), which is the start-of-the-art DC-DC converter. The positive output elementary super lift Luo converter performs the voltage conversion from positive source voltage to positive load voltage. This paper proposes a HMSMC capable of providing the good steady state and dynamic performance compared to conventional controllers. Dynamic equations describing the positive output elementary super lift luo converter are derived by using state space average method. The simulation model of the positive output elementary super lift Luo converter with its control circuit is implemented in Matlab/Simulink. The HMSMC for positive output elementary super lift Luo converter is tested for line changes, load changes and also for components variations.

Keywords: DC-DC converter, Positive output elementarysuper lift Luo converter (POESLLC), Hysteresis modulation basedsliding mode control (HMSMC).

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Authors: C. Ardil

Abstract:

Intuitionistic fuzzy sets (IFS), Pythagorean fuzzy sets (PyFS), Picture fuzzy sets (PFS), q-rung orthopair fuzzy sets (q-ROF), Spherical fuzzy sets (SFS), T-spherical FS, and Neutrosophic sets (NS) are reviewed as multidimensional extensions of fuzzy sets in order to more explicitly and informatively describe the opinions of decision-making experts under uncertainty. To handle operations with standard fuzzy sets (SFS), the necessary operators; weighted arithmetic mean (WAM), weighted geometric mean (WGM), and Minkowski distance function are defined. The algorithm of the proposed proximity measure method (PMM) is provided with a multiple criteria group decision making method (MCDM) for use in a standard fuzzy set environment. To demonstrate the feasibility of the proposed method, the problem of selecting the best drone for an Air Force procurement request is used. The proximity measure method (PMM) based multidimensional standard fuzzy sets (SFS) is introduced to demonstrate its use with an issue involving unmanned combat aircraft selection.

Keywords: standard fuzzy sets (SFS), unmanned combat aircraft selection, multiple criteria decision making (MCDM), proximity measure method (PMM).

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Authors: O. C. Nosiri, V. E. Idigo, C. O. Ohaneme, K. A. Akpado

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Coverage and capacity performance in a cellular network determines the system potentials. If the coverage radius is limited, end users suffer poor service quality, if the system capacity reduces, fewer subscribers will be accommodated. This paper investigated the performance effects of the noise rise caused by the spurious emission from a co-located jammer involving downlink frequency of CDMA2000 and uplink frequency of WCDMA operating at 1.9GHz. Measurements were carried out to evaluate the impact on the coverage radius and the system capacity.

Keywords: Capacity, Co-location, Coverage, Noise rise.

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Authors: Hamidreza Bagheri, Alireza Shariati

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There are many difficulties in the purification of raw components and products. However, researchers are seeking better ways for purification. One of the recent methods is extraction using supercritical fluids. In this study, the phase equilibria of benzoic acid -supercritical carbon dioxide system were investigated. Regarding the phase equilibria of this system, the modeling of solid-supercritical fluid behavior was performed using the Perturbed-Chain Statistical Association Fluid Theory (PC-SAFT) and Peng-Robinson equations of state (PR EoS). For this purpose, five PC-SAFT EoS parameters for pure benzoic acid were obtained using its experimental vapor pressure. Benzoic acid has association sites and the behavior of the benzoic acid-supercritical fluid system was well predicted using both equations of state, while the binary interaction parameter values for PR EoS were negative. Genetic algorithm, which is one of the most accurate global optimization algorithms, was also used to optimize the pure benzoic acid parameters and the binary interaction parameters. The AAD% value for the PC-SAFT EoS, were 0.22 for the carbon dioxide-benzoic acid system.

Keywords: Supercritical fluids, Solubility, Solid, PC-SAFT EoS, Genetic algorithm.

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Authors: J. A. Lopez, J. E. Olguín, C. Camargo, G. A. Quijano, R. Martínez

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An anthropometric study applied to 1,115 students of the Faculty of Chemical Sciences and Engineering of the Autonomous University of California. Thirteen individual measurements were taken in a sitting position. The results obtained allow forming a reliable anthropometric database for statistical studies and analysis and inferences of specific distributions, so the opinion of experts in occupational medicine recommendations may emit to reduce risks resulting in an alteration of the vital signs during the execution of their school activities. Another use of these analyses is to use them as a reliable reference for future deeper research, to the design of spaces, tools, utensils, workstations, with anthropometric dimensions and ergonomic characteristics suitable to use.

Keywords: Anthropometry, vital signs, students.

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Authors: V. L. M. F. Capellini, A. P. P. M. Maturana, N. C. M. Brondino, M. B. C. L. B. M. Peixoto, A. J. Broughton

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A paradigm shift is a process. The process of implementing inclusive education, a system constructed to support all learners, requires planning, identification, experimentation, and evaluation. In this vein, the purpose of the present study was to evaluate the capacity of one Brazilian state school systems to provide special education students with a quality inclusive education. This study originated at the behest of concerned families of students with special needs who filed complaints with the Municipality of Bauru, São Paulo. These families claimed, 1) children with learning differences and educational needs had not been identified for services, and 2) those who had been identified had not received sufficient specialized educational assistance (SEA) in schools across the City of Bauru. Hence, the Office of Civil Rights for the state of São Paulo (Ministério Público de São Paulo) summoned the local higher education institution, UNESP, to design a research study to investigate these allegations. In this exploratory study, descriptive data were gathered from all elementary and middle schools including 58 state schools and 17 city schools, for a total of 75 schools overall. Data collection consisted of each school's annual strategic action plan, surveys and interviews with all school stakeholders to determine their perceptions of the inclusive education available to students with Special Education Needs (SEN). The data were collected as one of four stages in a larger study which also included field observations of a focal students' experience and a continuing education course for all teachers and administrators in both state and city schools. For the purposes of this study, the researchers were interested in understanding the perceptions of school staff, parents, and students across all schools. Therefore, documents and surveys from 75 schools were analyzed for adherence to federal legislation guaranteeing students with SEN the right to special education assistance within the regular school setting. Results shows that while some schools recognized the legal rights of SEN students to receive special education, the plans to actually deliver services were absent. In conclusion, the results of this study revealed both school staff and families have insufficient planning and accessibility resources, and the schools have inadequate infrastructure for full-time support to SEN students, i.e., structures and systems to support the identification of SEN and delivery of services within schools of Bauru, SP. Having identified the areas of need, the city is now prepared to take next steps in the process toward preparing all schools to be inclusive.

Keywords: Inclusive education, special education, special needs.

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Authors: Hisham M. Abourayana, Nuri A. Zreiba, Abdulkader M. Elamin

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Polymer-like organic thin films were deposited on both aluminum alloy type 6061 and glass substrates at room temperature by Plasma Enhanced Chemical Vapor Deposition (PECVD) methodusing benzene and hexamethyldisiloxane (HMDSO) as precursor materials. The surface and physical properties of plasma-polymerized organic thin films were investigated at different r.f. powers. The effects of benzene/argon ratio on the properties of plasma polymerized benzene films were also investigated. It is found that using benzene alone results in a non-coherent and non-adherent powdery deposited material. The chemical structure and surface properties of the asgrown plasma polymerized thin films were analyzed on glass substrates with FTIR and contact angle measurements. FTIR spectra of benzene deposited film indicated that the benzene rings are preserved when increasing benzene ratio and/or decreasing r.f. powers. FTIR spectra of HMDSO deposited films indicated an increase of the hydrogen concentration and a decrease of the oxygen concentration with the increase of r.f. power. The contact angle (θ) of the films prepared from benzene was found to increase by about 43% as benzene ratio increases from 10% to 20%. θ was then found to decrease to the original value (51°) when the benzene ratio increases to 100%. The contact angle, θ, for both benzene and HMDSO deposited films were found to increase with r.f. power. This signifies that the plasma polymerized organic films have substantially low surface energy as the r.f power increases. The corrosion resistance of aluminum alloy substrate both bare and covered with plasma polymerized thin films was carried out by potentiodynamic polarization measurements in standard 3.5 wt. % NaCl solution at room temperature. The results indicate that the benzene and HMDSO deposited films are suitable for protection of the aluminum substrate against corrosion. The changes in the processing parameters seem to have a strong influence on the film protective ability. Surface roughness of films deposited on aluminum alloy substrate was investigated using scanning electron microscopy (SEM). The SEM images indicate that the surface roughness of benzene deposited films increase with decreasing the benzene ratio. SEM images of benzene and HMDSO deposited films indicate that the surface roughness decreases with increasing r.f. power. Studying the above parameters indicate that the films produced are suitable for specific practical applications.

Keywords: Plasma polymerization, potentiodynamic test, Contact angle.

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Authors: N. Todorovic, I. Bikit, J. Nikolov, S. Forkapic, D. Mrdja, S. Todorovic

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Interventional cardiologists are at greater risk from radiation exposure as a result of the procedures they undertake than most other medical specialists. A study was performed to evaluate operator dose during interventional cardiology procedures and to establish methods of operator dose reduction with a radiation protective device. Different procedure technique and use of protective tools can explain big difference in the annual equivalent dose received by the professionals. Strategies to prevent and monitor radiation exposure, advanced protective shielding and effective radiation monitoring methods should be applied.

Keywords: absorbed dose rate measurements, annualequivalent dose, protective device.

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Authors: Ruiheng Li, Amir Parsa Anvar, Amir M. Anvar, Tien-Fu Lu

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High redundancy and strong uncertainty are two main characteristics for underwater robotic manipulators with unlimited workspace and mobility, but they also make the motion planning and control difficult and complex. In order to setup the groundwork for the research on control schemes, the mathematical representation is built by using the Denavit-Hartenberg (D-H) method [9]&[12]; in addition to the geometry of the manipulator which was studied for establishing the direct and inverse kinematics. Then, the dynamic model is developed and used by employing the Lagrange theorem. Furthermore, derivation and computer simulation is accomplished using the MATLAB environment. The result obtained is compared with mechanical system dynamics analysis software, ADAMS. In addition, the creation of intelligent artificial skin using Interlink Force Sensing ResistorTM technology is presented as groundwork for future work

Keywords: Manipulator System, Robot, AUV, Denavit- Hartenberg method Lagrange theorem, MALTAB, ADAMS, Direct and Inverse Kinematics, Dynamics, PD Control-law, Interlink Force Sensing ResistorTM, intelligent artificial skin system.

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Authors: John O. Jacob, Abdullahi Mann, Olanrewaju I. Adeshina, Mohammed M. Ndamitso

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Strychnos spinosa, Detarium microcarpum, Diospyros mespiliformis, Dialium guineese and Gardenia ternifolia are some of the wild fruits consume in the villages around Minna, Niger State. This investigation was conducted to assess the nutritional potentials of these fruits both for human consumption and for possible application in animal feed formulations. Standard analytical methods were employed in the determination of the various nutritional parameters. The proximate analysis results showed that the moisture contents ranged between (6.17-10.70%); crude fat (2.04-8.85%); crude protein (5.16-6.80%); crude fibre (7.23-19.65%); Ash (3.46-5.56%); carbohydrate (57.77-69.79%); energy value (284.49-407 kcal/mg); Vitamin C (7.2-39.93 mg/100g). The mineral analysis shows that the selected wild fruits could contribute considerable amount of both micro and macro elements to human nutrition potassium, sodium and calcium range between; potassium (343.27-764.71%); sodium (155.04-348.44%); calcium (52.47-101%). The macro element for the fruits pulp were in the order K>Na>Mg>Ca, hence, they could be included in diet to supplement daily nutrient requirement and in animal feed formulations. The domestication of these fruits is also encouraged.

Keywords: Minerals, nutrition, supplements, wild fruits.

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Authors: M. Bougamouza, M. Bouhadef, T. Zitoun

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The aim of this study is to examine, through experimentation in the laboratory, the supercritical flow in the presence of an obstacle in a rectangular channel. The supercritical regime in the whole hydraulic channel is achieved by adding a convergent. We will observe the influence of the obstacle shape and dimension on the characteristics of the supercritical flow, mainly the free-surface elevation and the velocity profile. The velocity measurements have been conducted with the one dimension laser anemometry technique.

Keywords: Experiments, free-surface flow, hydraulic channel, uneven bottom, laser anemometry, supercritical regime.

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Authors: Noor M. Abdulfattah, Ahmed M. Khalafallah, Nabil A. Kartam

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Despite the evident benefits of building information modeling (BIM) to the construction industry, it faces significant implementation challenges in the State of Kuwait. This study investigates the awareness of construction stakeholders of BIM implementation challenges, and identifies various solutions to overcome these challenges. Specifically, the main objectives of this study are to: (1) characterize the barriers that deter utilization of BIM, (2) examine the awareness of engineers, architects, and construction stakeholders of these barriers, and (3) identify practical solutions to facilitate BIM utilization. A questionnaire survey was designed to collect data on the aforementioned objectives from local companies and senior BIM experts. It was found that engineers are highly aware of BIM implementation barriers. In addition, it was concluded from the questionnaire that the biggest barrier is the lack of BIM training. Based on expert feedback, the study concluded with a number of recommendations on how to overcome the barriers of BIM utilization. This should prove useful to the construction industry stakeholders and can lead to significant changes to design and construction practices.

Keywords: Building information modeling, construction, challenges, information technology.

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Authors: Takeshi Takeda

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The author conducted post-test analysis with the RELAP5/MOD3.3 code for an experiment using the ROSA/LSTF (rig of safety assessment/large-scale test facility) that simulated a 1% cold leg small-break loss-of-coolant accident under the failure of scram in a pressurized water reactor. The LSTF test assumed total failure of high-pressure injection system of emergency core cooling system. In the LSTF test, natural circulation contributed to maintain core cooling effect for a relatively long time until core uncovery occurred. The post-test analysis result confirmed inadequate prediction of the primary coolant distribution. The author created the phenomena identification and ranking table (PIRT) for each component. The author investigated the influences of uncertain parameters determined by the PIRT on the cladding surface temperature at a certain time during core uncovery within the defined uncertain ranges.

Keywords: LSTF, LOCA, scram, RELAP5.

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Authors: Deepak Goswami, Padma Lochan Hazarika, Kandarpa Kumar Sarma

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The customary practice of identifying industrial sickness is a set traditional techniques which rely upon a range of manual monitoring and compilation of financial records. It makes the process tedious, time consuming and often are susceptible to manipulation. Therefore, certain readily available tools are required which can deal with such uncertain situations arising out of industrial sickness. It is more significant for a country like India where the fruits of development are rarely equally distributed. In this paper, we propose an approach based on Artificial Neural Network (ANN) to deal with industrial sickness with specific focus on a few such units taken from a less developed north-east (NE) Indian state like Assam. The proposed system provides decision regarding industrial sickness using eight different parameters which are directly related to the stages of sickness of such units. The mechanism primarily uses certain signals and symptoms of industrial health to decide upon the state of a unit. Specifically, we formulate an ANN based block with data obtained from a few selected units of Assam so that required decisions related to industrial health could be taken. The system thus formulated could become an important part of planning and development. It can also contribute towards computerization of decision support systems related to industrial health and help in better management.

Keywords: Industrial, Health, Classification, ANN, MLP, MSE.

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Authors: M. Raciti Castelli, P. Cioppa, E. Benini

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This paper presents a CFD analysis of the flow around a 30° inclined flat plate of infinite span. Numerical predictions have been compared to experimental measurements, in order to assess the potential of the finite volume code of determining the aerodynamic forces acting on a flat plate invested by a fluid stream of infinite extent. Several turbulence models and spatial node distributions have been tested and flow field characteristics in the neighborhood of the flat plate have been numerically investigated, allowing the development of a preliminary procedure to be used as guidance in selecting the appropriate grid configuration and the corresponding turbulence model for the prediction of the flow field over a twodimensional inclined plate.

Keywords: CFD, lift, drag, flat plate

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Authors: Charline David, Alexandre Blondin Massé, Arnaud Zinflou

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We present a multiple equation time series approach for the short-term load forecasting applied to the electrical power load consumption for the whole Quebec province, in Canada. More precisely, we take into account three meteorological variables — temperature, cloudiness and wind speed —, and we use meteorological measurements taken at different locations on the territory. Our final model shows an average MAPE score of 1.79% over an 8-years dataset.

Keywords: Short-term load forecasting, special days, time series, multiple equations, parallelization, clustering.

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Authors: Mustafa M. Donma

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Metabolic syndrome (MetS) is characterized by a series of biochemical, physiological and anthropometric indicators and is a life-threatening health problem due to its close association with chronic diseases such as obesity, diabetes mellitus, hypertension, cancer and cardiovascular diseases. The syndrome deserves great interest both in adults and children. Particularly, children with morbid obesity have a great tendency to develop the disease. The diagnostic decision is not so easy and may not be complete particularly in the pediatric population. Therefore, preventive measures should be considered at this stage. The aim of the study was to develop a MetS index capable of predicting MetS, while children are at the morbid obesity stage. This study was performed on morbid obese (MO) children, which were divided into two groups. MO children, who do not possess MetS criteria comprised the first group (n = 44). The second group was composed of children with MetS diagnosis (n = 42). Anthropometric measurements including weight, height, waist circumference (WC), hip C, head C, neck C, biochemical tests including fasting blood glucose (FBG), insulin (INS), triglycerides (TRG), high density lipoprotein cholesterol (HDL-C) and blood pressure measurements (systolic (SBP) and diastolic (DBP)) were performed. Body fat percentage (BFP) values were determined by TANITA’s Bioelectrical Impedance Analysis technology. Body mass index and MetS indices were calculated. Descriptive statistics including median values, t-test, Mann Whitney U test, correlation-regression analysis were performed within the scope of data evaluation using the statistical package program, SPSS. Statistically significant mean differences were determined by a p value smaller than 0.05. Median values for MetSI and ADMI in MO (MetS-) and MO (MetS+) groups were calculated as 25.9 and 36.5 and 74.0 and 106.1, respectively. Corresponding mean ± SD values for BFPs were 35.9 ± 7.1 and 38.2 ± 7.7 in groups. Correlation analysis of these two indices with corresponding general BFP values exhibited significant association with ADMI, close to significance with MetSI in MO group. Any significant correlation was found with neither of the indices in MetS group. In conclusion, important associations observed with MetS indices in MO group were quite meaningful. The presence of these associations in MO group was important for showing the tendency towards the development of MetS in MO (MetS-) participants. The other index, ADMI, was more helpful for predictive purpose.

Keywords: Body fat percentage, child obesity, metabolic syndrome index, morbid obesity.

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Authors: Yasaswi Palagummi, Sareh Rowlands

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Generalised Zero-Shot Learning, often known as GZSL, is an advanced variant of zero-shot learning in which the samples in the unseen category may be either seen or unseen. GZSL methods typically have a bias towards the seen classes because they learn a model to perform recognition for both the seen and unseen classes using data samples from the seen classes. This frequently leads to the misclassification of data from the unseen classes into the seen classes, making the task of GZSL more challenging. In this work, we propose an approach leveraging the Shifted Window based Self-Attention in the Swin Transformer (Swin-GZSL) to work in the inductive GZSL problem setting. We run experiments on three popular benchmark datasets: CUB, SUN, and AWA2, which are specifically used for ZSL and its other variants. The results show that our model based on Swin Transformer has achieved state-of-the-art harmonic mean for two datasets - AWA2 and SUN and near-state-of-the-art for the other dataset - CUB. More importantly, this technique has a linear computational complexity, which reduces training time significantly. We have also observed less bias than most of the existing GZSL models.

Keywords: Generalised Zero-shot Learning, Inductive Learning, Shifted-Window Attention, Swin Transformer, Vision Transformer.

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Authors: Jun Seok Kim, Cheong-Sool Park, Jun-Geol Baek, Sung-Shick Kim

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Control chart pattern recognition is one of the most important tools to identify the process state in statistical process control. The abnormal process state could be classified by the recognition of unnatural patterns that arise from assignable causes. In this study, a wavelet based neural network approach is proposed for the recognition of control chart patterns that have various characteristics. The procedure of proposed control chart pattern recognizer comprises three stages. First, multi-resolution wavelet analysis is used to generate time-shape and time-frequency coefficients that have detail information about the patterns. Second, distance based features are extracted by a bi-directional Kohonen network to make reduced and robust information. Third, a back-propagation network classifier is trained by these features. The accuracy of the proposed method is shown by the performance evaluation with numerical results.

Keywords: Control chart pattern recognition, Multi-resolution wavelet analysis, Bi-directional Kohonen network, Back-propagation network, Feature extraction.

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Authors: Alireza Vafaei Sadr, Vida Abedi, Jiang Li, Ramin Zand

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Missing data is a common challenge in medical research and can lead to biased or incomplete results. When the data bias leaks into models, it further exacerbates health disparities; biased algorithms can lead to misclassification and reduced resource allocation and monitoring as part of prevention strategies for certain minorities and vulnerable segments of patient populations, which in turn further reduce data footprint from the same population – thus, a vicious cycle. This study compares the performance of six imputation techniques grouped into Linear and Non-Linear models, on two different real-world electronic health records (EHRs) datasets, representing 17864 patient records. The mean absolute percentage error (MAPE) and root mean squared error (RMSE) are used as performance metrics, and the results show that the Linear models outperformed the Non-Linear models in terms of both metrics. These results suggest that sometimes Linear models might be an optimal choice for imputation in laboratory variables in terms of imputation efficiency and uncertainty of predicted values.

Keywords: EHR, Machine Learning, imputation, laboratory variables, algorithmic bias.

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Authors: Dhiflaoui Hafedh, Khlifi Kaouthar, Ben Cheikh Larbi Ahmed

Abstract:

The present study deals with the characterization of CrSiN coatings obtained by PVD magnetron sputtering systems. CrSiN films were deposited with different Si contents, in order to check the effect of at.% variation on the different properties of the Cr–N system. Coatings were characterized by scanning electron microscopy (SEM) for thickness measurements, X-ray diffraction. Surface morphology and the roughness characteristics were explored using AFM, Mechanicals properties, elastic and plastic deformation resistance of thin films were investigated using nanoindentation test. We observed that the Si addition improved the hardness and the Young’s modulus of the Cr–N system. Indeed, the hardness value is 18,56 GPa for CrSiN coatings. Besides, the Young’s modulus value is 224,22 GPa for CrSiN coatings for Si content of 1.2 at.%.

Keywords: Thin film, mechanicals properties, PVD.

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Authors: Alan Walsh, Peter Walker

Abstract:

Differences in commercial, professional and personal cultural traditions between western consultants and project sponsors in the Gulf Cooperation Council (GCC) region are potentially significant in the workplace, and this can impact on project outcomes. These cultural differences can, for example, result in conflict amongst senior managers, which can negatively impact the megaproject. New entrants to the GCC often experience ‘culture shock’ as they attempt to integrate into their unfamiliar environments. Megaprojects are unique ventures with individual project characteristics, which need to be considered when managing their associated risks. Megaproject research to date has mostly ignored the significance of the absence of cultural congruence in the GCC, which is surprising considering that there are large volumes of megaprojects in various stages of construction in the GCC. An initial step to dealing with cultural issues is to acknowledge culture as a significant risk factor (SRF). This paper seeks to understand the criticality for western consultants to address these risks. It considers the cultural barriers that exist between GCC sponsors and western consultants and examines the cultural distance between the key actors. Initial findings suggest the presence to a certain extent of ethnocentricity. Other cultural clashes arise out of a lack of appreciation of the customs, practices and traditions of ‘the Other’, such as the need for avoiding public humiliation and the hierarchal significance rankings. The concept and significance of cultural shock as part of the integration process for new arrivals are considered. Culture shock describes the state of anxiety and frustration resulting from the immersion in a culture distinctly different from one's own. There are potentially substantial project risks associated with underestimating the process of cultural integration. This paper examines two distinct but intertwined issues: the societal and professional culture differences associated with expatriate assignments. A case study examines the cultural congruences between GCC sponsors and American, British and German consultants, over a ten-year cycle. This provides indicators as to which nationalities encountered the most profound cultural issues and the nature of these. GCC megaprojects are typically intensive fast track demanding ventures, where consultant turnover is high. The study finds that building trust-filled relationships is key to successful project team integration and therefore, to successful megaproject execution. Findings indicate that both professional and social inclusion processes have steep learning curves. Traditional risk management practice is to approach any uncertainty in a structured way to mitigate the potential impact on project outcomes. This research highlights cultural risk as a significant factor in the management of GCC megaprojects. These risks arising from high staff turnover typically include loss of project knowledge, delays to the project, cost and disruption in replacing staff. This paper calls for cultural risk to be recognised as an SRF, as the first step to developing risk management strategies, and to reduce staff turnover for western consultants in GCC megaprojects.

Keywords: Western consultants in megaprojects, national culture impacts on GCC Megaprojects, significant risk factors in megaprojects, professional culture in megaprojects.

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Authors: Tarifa S. Almulhim, Ludmil Mikhailov, Dong-Ling Xu

Abstract:

In this paper, a method for deriving a group priority vector in the Fuzzy Analytic Network Process (FANP) is proposed. By introducing importance weights of multiple decision makers (DMs) based on their experiences, the Fuzzy Preferences Programming Method (FPP) is extended to a fuzzy group prioritization problem in the FANP. Additionally, fuzzy pair-wise comparison judgments are presented rather than exact numerical assessments in order to model the uncertainty and imprecision in the DMs- judgments and then transform the fuzzy group prioritization problem into a fuzzy non-linear programming optimization problem which maximize the group satisfaction. Unlike the known fuzzy prioritization techniques, the new method proposed in this paper can easily derive crisp weights from incomplete and inconsistency fuzzy set of comparison judgments and does not require additional aggregation producers. Detailed numerical examples are used to illustrate the implement of our approach and compare with the latest fuzzy prioritization method.

Keywords: Fuzzy Analytic Network Process (FANP), Fuzzy Non-linear Programming, Fuzzy Preferences Programming Method (FPP), Multiple Criteria Decision-Making (MCDM), Triangular Fuzzy Number.

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