Search results for: cumulative absolute velocity
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2519

Search results for: cumulative absolute velocity

899 Numerical Simulation of External Flow Around D-Shaped Cylinders

Authors: Ouldouz Nourani Zonouz, Mehdi Salmanpour

Abstract:

Investigation and analysis of flow behavior around different shapes bluff bodies is one of the reputed topics for several years. The importance of these researches is about the unwanted phenomena called flow separation. The location of separation and the size of the wake region should be considered in different industrial designs. In this research a bluff body with D-shaped cross section has been analyzed. In circular cylinder flow separation point changes with Reynolds number but in D-Shaped cylinder there is fix flow separation point. So there is more wake steadiness in D-Shaped cylinder as compared to Circular cylinder and drag reduction because of wake steadiness. In the present work CFD simulation is carried out for flow past a D-Shaped cylinder to see the wake behavior. The Reynolds number regime currently studied corresponds to low Reynolds number and nominally two-dimensional wake. Also the effect of D-Shaped cylinders on the rate of heat transfer has been considered. Various results such as velocity, pressure and temperature contours and also some dimensionless numbers like drag coefficient, pressure coefficient and Nusselt number calculated for different cases.

Keywords: D-shaped, CFD, external flow, low Reynolds number, square cylinder

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898 High-Quality Flavor of Black Belly Pork under Lightning Corona Discharge Using Tesla Coil for High Voltage Education

Authors: Kyung-Hoon Jang, Jae-Hyo Park, Kwang-Yeop Jang, Dongjin Kim

Abstract:

The Tesla coil is an electrical resonant transformer circuit designed by inventor Nikola Tesla in 1891. It is used to produce high voltage, low current and high frequency alternating current electricity. Tesla experimented with a number of different configurations consisting of two or sometimes three coupled resonant electric circuits. This paper focuses on development and high voltage education to apply a Tesla coil to cuisine for high quality flavor and taste conditioning as well as high voltage education under 50 kV corona discharge. The result revealed that the velocity of roasted black belly pork by Tesla coil is faster than that of conventional methods such as hot grill and steel plate etc. depending on applied voltage level and applied voltage time. Besides, carbohydrate and crude protein increased, whereas natrium and saccharides significantly decreased after lightning surge by Tesla coil. This idea will be useful in high voltage education and high voltage application.

Keywords: corona discharge, Tesla coil, high voltage application, high voltage education

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897 The Use of Hec Ras One-Dimensional Model and Geophysics for the Determination of Flood Zones

Authors: Ayoub El Bourtali, Abdessamed Najine, Amrou Moussa Benmoussa

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It is becoming more and more necessary to manage flood risk, and it must include all stakeholders and all possible means available. The goal of this work is to map the vulnerability of the Oued Derna-region Tagzirt flood zone in the semi-arid region. This is about implementing predictive models and flood control. This allows for the development of flood risk prevention plans. In this study, A resistivity survey was conducted over the area to locate and evaluate soil characteristics in order to calculate discharges and prevent flooding for the study area. The development of a one-dimensional (1D) hydrodynamic model of the Derna River was carried out in HEC-RAS 5.0.4 using a combination of survey data and spatially extracted cross-sections and recorded river flows. The study area was hit by several extreme floods, causing a lot of property loss and loss of life. This research focuses on the most recent flood events, based on the collected data, the water level, river flow and river cross-section were analyzed. A set of flood levels were obtained as the outputs of the hydraulic model and the accuracy of the simulated flood levels and velocity.

Keywords: derna river, 1D hydrodynamic model, flood modelling, HEC-RAS 5.0.4

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896 Experimental Verification of On-Board Power Generation System for Vehicle Application

Authors: Manish Kumar, Krupa Shah

Abstract:

The usage of renewable energy sources is increased day by day to overcome the dependency on fossil fuels. The wind energy is considered as a prominent source of renewable energy. This paper presents an approach for utilizing wind energy obtained from moving the vehicle for cell-phone charging. The selection of wind turbine, blades, generator, etc. is done to have the most efficient system. The calculation procedure for power generated and drag force is shown to know the effectiveness of the proposal. The location of the turbine is selected such that the system remains symmetric, stable and has the maximum induced wind. The calculation of the generated power at different velocity is presented. The charging is achieved for the speed 30 km/h and the system works well till 60 km/h. The model proposed seems very useful for the people traveling long distances in the absence of mobile electricity. The model is very economical and easy to fabricate. It has very less weight and area that makes it portable and comfortable to carry along. The practical results are shown by implementing the portable wind turbine system on two-wheeler.

Keywords: cell-phone charging, on-board power generation, wind energy, vehicle

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895 A Physical Treatment Method as a Prevention Method for Barium Sulfate Scaling

Authors: M. A. Salman, G. Al-Nuwaibit, M. Safar, M. Rughaibi, A. Al-Mesri

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Barium sulfate (BaSO₄) is a hard scaling usually precipitates on the surface of equipment in many industrial systems, as oil and gas production, desalination and cooling and boiler operation. It is a scale that extremely resistance to both chemical and mechanical cleaning. So, BaSO₄ is a problematic and expensive scaling. Although barium ions are present in most natural waters at a very low concentration as low as 0.008 mg/l, it could result of scaling problems in the presence of high concentration of sulfate ion or when mixing with incompatible waters as in oil produced water. The scaling potential of BaSO₄ using seawater at the intake of seven desalination plants in Kuwait, brine water and Kuwait oil produced water was calculated and compared then the best location in regards of barium sulfate scaling was reported. Finally, a physical treatment method (magnetic treatment method) and chemical treatment method were used to control BaSO₄ scaling using saturated solutions at different operating temperatures, flow velocities, feed pHs and different magnetic strengths. The results of the two methods were discussed, and the more economical one with the reasonable performance was recommended, which is the physical treatment method.

Keywords: magnetic field strength, flow velocity, retention time, barium sulfate

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894 CFD Simulation for Flow Behavior in Boiling Water Reactor Vessel and Upper Pool under Decommissioning Condition

Authors: Y. T. Ku, S. W. Chen, J. R. Wang, C. Shih, Y. F. Chang

Abstract:

In order to respond the policy decision of non-nuclear homes, Tai Power Company (TPC) will provide the decommissioning project of Kuosheng Nuclear power plant (KSNPP) to meet the regulatory requirement in near future. In this study, the computational fluid dynamics (CFD) methodology has been employed to develop a flow prediction model for boiling water reactor (BWR) with upper pool under decommissioning stage. The model can be utilized to investigate the flow behavior as the vessel combined with upper pool and continuity cooling system. At normal operating condition, different parameters are obtained for the full fluid area, including velocity, mass flow, and mixing phenomenon in the reactor pressure vessel (RPV) and upper pool. Through the efforts of the study, an integrated simulation model will be developed for flow field analysis of decommissioning KSNPP under normal operating condition. It can be expected that a basis result for future analysis application of TPC can be provide from this study.

Keywords: CFD, BWR, decommissioning, upper pool

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893 Assessing the Validity and Reliability of Neuromuscular Performance Tests in Professional Basketball Players

Authors: Álvaro de Pedro Múñez, Óscar García García, Tania Álvarez Yates, Virginia Serrano Gómez

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This study aimed to analyze professional basketball player´s neuromuscular behaviour. The main goal was to describe the neuromuscular performance of elite male basketball players and to analyze the validity and reliability of different tests. The tests used were Squat Jump (SJ), Countermovement Free), and 5m, 10m, and 20m sprint tests. All these tests were carried out during the preseason. 100 professional basketball players participated in this study; we used 2 classification variables: performance level (Leb Gold, BBL, and BCL), as well as position (Bigs and Guards). The application of the Kolmogorov-Smirnov test, in conjunction with the Lilliefors test, showed that the sample distribution was normal, linear, and homoscedastic. The relative reliability analysis was carried out by calculating the Intraclass Correlation Index (ICC). We found all variables to have a high validity and reliability. The coefficient of variation (CV) was calculated for raw data and after log-transformed and used as an absolute reliability indicator. The intraclass correlation coefficients (ICC) and coefficient of variation (CV) for the various tests are the following. For the Countermovement Jump (CMJ), the right leg showed an ICC of 0.94 (CV: 7.8%), and the left leg had an ICC of 0.84 (CV: 11.2%). For the sprint tests, the 5m sprint demonstrated excellent reliability with an intraclass correlation coefficient (ICC) of 0.81 and a coefficient of variation (CV) of 3.2%. The 10m sprint exhibited an ICC of 0.91 and a CV of 1.0%, while the 20m sprint achieved the highest reliability with an ICC of 0.92 and a CV of 0.8%. Regarding jump performance, the Squat Jump (SJ) displayed an ICC of 0.96 with a CV of 2.8%, and the Countermovement Jump (CMJ) showed a slightly lower but still strong reliability with an ICC of 0.93 and a CV of 6.7%. Lastly, the "CMJ free" test exhibited an ICC of 0.97 (CV: 5.2%). The tests demonstrated high reliability, with ICC values ranging from 0.81 to 0.97. The 5m, 10m, and 20m sprints, as well as the CMJ and SJ tests, showed strong consistency, particularly the 10m and 20m sprints (ICC 0.91-0.92). Coefficients of variation were low, indicating precise and stable measurements suitable for performance assessment.

Keywords: neuromuscular performance, basketball players, validity and reliability, intraclass correlation coefficient, vertical jump, sprint tests

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892 Magnetohydrodynamic (MHD) Flow of Cu-Water Nanofluid Due to a Rotating Disk with Partial Slip

Authors: Tasawar Hayat, Madiha Rashid, Maria Imtiaz, Ahmed Alsaedi

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This problem is about the study of flow of viscous fluid due to rotating disk in nanofluid. Effects of magnetic field, slip boundary conditions and thermal radiations are encountered. An incompressible fluid soaked the porous medium. In this model, nanoparticles of Cu is considered with water as the base fluid. For Copper-water nanofluid, graphical results are presented to describe the influences of nanoparticles volume fraction (φ) on velocity and temperature fields for the slip boundary conditions. The governing differential equations are transformed to a system of nonlinear ordinary differential equations by suitable transformations. Convergent solution of the nonlinear system is developed. The obtained results are analyzed through graphical illustrations for different parameters. Moreover, the features of the flow and heat transfer characteristics are analyzed. It is found that the skin friction coefficient and heat transfer rate at the surface are highest in copper-water nanofluid.

Keywords: MHD nanofluid, porous medium, rotating disk, slip effect

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891 Comparison of Two Neural Networks To Model Margarine Age And Predict Shelf-Life Using Matlab

Authors: Phakamani Xaba, Robert Huberts, Bilainu Oboirien

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The present study was aimed at developing & comparing two neural-network-based predictive models to predict shelf-life/product age of South African margarine using free fatty acid (FFA), water droplet size (D3.3), water droplet distribution (e-sigma), moisture content, peroxide value (PV), anisidine valve (AnV) and total oxidation (totox) value as input variables to the model. Brick margarine products which had varying ages ranging from fresh i.e. week 0 to week 47 were sourced. The brick margarine products which had been stored at 10 & 25 °C and were characterized. JMP and MATLAB models to predict shelf-life/ margarine age were developed and their performances were compared. The key performance indicators to evaluate the model performances were correlation coefficient (CC), root mean square error (RMSE), and mean absolute percentage error (MAPE) relative to the actual data. The MATLAB-developed model showed a better performance in all three performance indicators. The correlation coefficient of the MATLAB model was 99.86% versus 99.74% for the JMP model, the RMSE was 0.720 compared to 1.005 and the MAPE was 7.4% compared to 8.571%. The MATLAB model was selected to be the most accurate, and then, the number of hidden neurons/ nodes was optimized to develop a single predictive model. The optimized MATLAB with 10 neurons showed a better performance compared to the models with 1 & 5 hidden neurons. The developed models can be used by margarine manufacturers, food research institutions, researchers etc, to predict shelf-life/ margarine product age, optimize addition of antioxidants, extend shelf-life of products and proactively troubleshoot for problems related to changes which have an impact on shelf-life of margarine without conducting expensive trials.

Keywords: margarine shelf-life, predictive modelling, neural networks, oil oxidation

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890 Empirical Modeling of Air Dried Rubberwood Drying System

Authors: S. Khamtree, T. Ratanawilai, C. Nuntadusit

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Rubberwood is a crucial commercial timber in Southern Thailand. All processes in a rubberwood production depend on the knowledge and expertise of the technicians, especially the drying process. This research aims to develop an empirical model for drying kinetics in rubberwood. During the experiment, the temperature of the hot air and the average air flow velocity were kept at 80-100 °C and 1.75 m/s, respectively. The moisture content in the samples was determined less than 12% in the achievement of drying basis. The drying kinetic was simulated using an empirical solver. The experimental results illustrated that the moisture content was reduced whereas the drying temperature and time were increased. The coefficient of the moisture ratio between the empirical and the experimental model was tested with three statistical parameters, R-square (), Root Mean Square Error (RMSE) and Chi-square (χ²) to predict the accuracy of the parameters. The experimental moisture ratio had a good fit with the empirical model. Additionally, the results indicated that the drying of rubberwood using the Henderson and Pabis model revealed the suitable level of agreement. The result presented an excellent estimation (= 0.9963) for the moisture movement compared to the other models. Therefore, the empirical results were valid and can be implemented in the future experiments.

Keywords: empirical models, rubberwood, moisture ratio, hot air drying

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889 Developing a DNN Model for the Production of Biogas From a Hybrid BO-TPE System in an Anaerobic Wastewater Treatment Plant

Authors: Hadjer Sadoune, Liza Lamini, Scherazade Krim, Amel Djouadi, Rachida Rihani

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Deep neural networks are highly regarded for their accuracy in predicting intricate fermentation processes. Their ability to learn from a large amount of datasets through artificial intelligence makes them particularly effective models. The primary obstacle in improving the performance of these models is to carefully choose the suitable hyperparameters, including the neural network architecture (number of hidden layers and hidden units), activation function, optimizer, learning rate, and other relevant factors. This study predicts biogas production from real wastewater treatment plant data using a sophisticated approach: hybrid Bayesian optimization with a tree-structured Parzen estimator (BO-TPE) for an optimised deep neural network (DNN) model. The plant utilizes an Upflow Anaerobic Sludge Blanket (UASB) digester that treats industrial wastewater from soft drinks and breweries. The digester has a working volume of 1574 m3 and a total volume of 1914 m3. Its internal diameter and height were 19 and 7.14 m, respectively. The data preprocessing was conducted with meticulous attention to preserving data quality while avoiding data reduction. Three normalization techniques were applied to the pre-processed data (MinMaxScaler, RobustScaler and StandardScaler) and compared with the Non-Normalized data. The RobustScaler approach has strong predictive ability for estimating the volume of biogas produced. The highest predicted biogas volume was 2236.105 Nm³/d, with coefficient of determination (R2), mean absolute error (MAE), and root mean square error (RMSE) values of 0.712, 164.610, and 223.429, respectively.

Keywords: anaerobic digestion, biogas production, deep neural network, hybrid bo-tpe, hyperparameters tuning

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888 CFD Prediction of the Round Elbow Fitting Loss Coefficient

Authors: Ana Paula P. dos Santos, Claudia R. Andrade, Edson L. Zaparoli

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Pressure loss in ductworks is an important factor to be considered in design of engineering systems such as power-plants, refineries, HVAC systems to reduce energy costs. Ductwork can be composed by straight ducts and different types of fittings (elbows, transitions, converging and diverging tees and wyes). Duct fittings are significant sources of pressure loss in fluid distribution systems. Fitting losses can be even more significant than equipment components such as coils, filters, and dampers. At the present work, a conventional 90o round elbow under turbulent incompressible airflow is studied. Mass, momentum, and k-e turbulence model equations are solved employing the finite volume method. The SIMPLE algorithm is used for the pressure-velocity coupling. In order to validate the numerical tool, the elbow pressure loss coefficient is determined using the same conditions to compare with ASHRAE database. Furthermore, the effect of Reynolds number variation on the elbow pressure loss coefficient is investigated. These results can be useful to perform better preliminary design of air distribution ductworks in air conditioning systems.

Keywords: duct fitting, pressure loss, elbow, thermodynamics

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887 Changing Subjective Well-Being and Social Trust in China: 2010-2020

Authors: Mengdie Ruan

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The authors investigate how subjective well-being (SWB) and social trust changed in China over the period 2010–2020 by relying on data from six rounds of the China Family Panel Studies (CFPS), then re-examine Easterlin’s hypothesis for China, with a more focus on the role of social trust and estimate income-compensating differentials for social trust. They find that the evolution of well-being is not sensitive to the measures of well-being one uses. Specifically, self-reported life satisfaction scores and hedonic happiness scores experienced a significant increase across all income groups from 2010 to 2020. Social trust seems to have increased based on CFPS in China for all socioeconomic classes in recent years, and male, urban resident individuals with higher income have a higher social trust at a given point in time and over time. However, when we use an alternative measure of social trust, out-group trust, which is a more valid measure of generalized trust and represents “most people”, social trust in China literally declines, and the level is extremely low. In addition, this paper also suggests that in the typical query on social trust, the term "most people" mostly denotes in-groups in China, which contrasts sharply with most Western countries where it predominantly connotes out-groups. Individual fixed effects analysis of well-being that controls for time-invariant variables reveals social trust and relative social status are important correlates of life satisfaction and happiness, whereas absolute income plays a limited role in boosting an individual’s well-being. The income-equivalent value for social capital is approximately tripling of income. It has been found that women, urban and coastal residents, and people with higher income, young people, those with high education care more about social trust in China, irrespective of measures on SWB. Policy aiming at preserving and enhancing SWB should focus on social capital besides economic growth.

Keywords: subjective well-being, life satisfaction, happiness, social trust, China

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886 Design of a Standard Weather Data Acquisition Device for the Federal University of Technology, Akure Nigeria

Authors: Isaac Kayode Ogunlade

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Data acquisition (DAQ) is the process by which physical phenomena from the real world are transformed into an electrical signal(s) that are measured and converted into a digital format for processing, analysis, and storage by a computer. The DAQ is designed using PIC18F4550 microcontroller, communicating with Personal Computer (PC) through USB (Universal Serial Bus). The research deployed initial knowledge of data acquisition system and embedded system to develop a weather data acquisition device using LM35 sensor to measure weather parameters and the use of Artificial Intelligence(Artificial Neural Network - ANN)and statistical approach(Autoregressive Integrated Moving Average – ARIMA) to predict precipitation (rainfall). The device is placed by a standard device in the Department of Meteorology, Federal University of Technology, Akure (FUTA) to know the performance evaluation of the device. Both devices (standard and designed) were subjected to 180 days with the same atmospheric condition for data mining (temperature, relative humidity, and pressure). The acquired data is trained in MATLAB R2012b environment using ANN, and ARIMAto predict precipitation (rainfall). Root Mean Square Error (RMSE), Mean Absolute Error (MAE), Correction Square (R2), and Mean Percentage Error (MPE) was deplored as standardize evaluation to know the performance of the models in the prediction of precipitation. The results from the working of the developed device show that the device has an efficiency of 96% and is also compatible with Personal Computer (PC) and laptops. The simulation result for acquired data shows that ANN models precipitation (rainfall) prediction for two months (May and June 2017) revealed a disparity error of 1.59%; while ARIMA is 2.63%, respectively. The device will be useful in research, practical laboratories, and industrial environments.

Keywords: data acquisition system, design device, weather development, predict precipitation and (FUTA) standard device

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885 Experimentally Validated Analytical Model for Thermal Analysis of Multi-Stage Depressed Collector

Authors: Vishant Gahlaut, A Mercy Latha, Sanjay Kumar Ghosh

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Multi-stage depressed collectors (MDC) are used as an efficiency enhancement technique in traveling wave tubes the high-energy electron beam, after its interaction with the RF signal, gets velocity sorted and collected at various depressed electrodes of the MDC. The ultimate goal is to identify an optimum thermal management scheme (cooling mechanism) that could extract the heat efficiently from the electrodes. Careful thermal analysis, incorporating the cooling mechanism is required to ensure that the maximum temperature does not exceed the safe limits. A simple analytical model for quick prediction of the thermal has been developed. The model has been developed for the worst-case un-modulated DC condition, where all the thermal power is dissipated in the last electrode (typically, fourth electrode in the case of the four-stage depressed collector). It considers the thermal contact resistances at various braze joints accounting for the practical non-uniformities. Analytical results obtained from the model have been validated with simulated and experimental results.

Keywords: multi-stage depressed collector, TWTs, thermal contact resistance, thermal management

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884 Anti-Ulcer Activity of Hydro Alcoholic Extract of Ficus bengalensis Linn Bark in Experimental Rats

Authors: Jagdish Baheti, Sampat Navale

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The present study was performed to evaluate the anti-ulcerogenic activity of hydro-alcoholic extract of Ficus bengalensis Linn. against ethanol-induced gastric mucosal injury in rats and pylorus ligation gastric secretion in rats. Five groups of adult wistar rats were orally pre-treated respectively with carboxy methyl cellulose (CMC) solution (ulcer control group), Omeprazole 20 mg/kg (reference group), and 100, 200 and 300 mg/kg F. bengalensis Linn. bark extract in CMC solution (experimental groups), one hour before oral administration of absolute ethanol to generate gastric mucosal injury. Rats were sacrificed and the ulcer index, gastric volume, gastric pH, free acidity, total acidity of the gastric content was determined. Grossly, the ulcer control group exhibited severe mucosal injury, whereas pre-treatment with F. bengalensis Linn. bark extract exhibited significant protection of gastric mucosal injury in both model. Histological studies revealed that ulcer control group exhibited severe damage of gastric mucosa, along with edema and leucocytes infiltration of submucosal layer compared to rats pre-treated with F. bengalensis Linn. bark extract which showed gastric mucosal protection, reduction or absence of edema and leucocytes infiltration of submucosal layer. Acute toxicity study did not manifest any toxicological signs in rats. The present finding suggests that F. bengalensis Linn. bark extract promotes ulcer protection as ascertained grossly and histologically compared to the ulcer control group.

Keywords: Ficus bengalensis Linn., gastric ulcer, hydroalcoholic, pylorus ligation

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883 Effect of Internal Heat Generation on Free Convective Power Law Variable Temperature Past Vertical Plate Considering Exponential Variable Viscosity and Thermal Diffusivity

Authors: Tania Sharmin Khaleque, Mohammad Ferdows

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The flow and heat transfer characteristics of a convection with temperature-dependent viscosity and thermal diffusivity along a vertical plate with internal heat generation effect have been studied. The plate temperature is assumed to follow a power law of the distance from the leading edge. The resulting governing two-dimensional equations are transformed using suitable transformations and then solved numerically by using fifth order Runge-Kutta-Fehlberg scheme with a modified version of the Newton-Raphson shooting method. The effects of the various parameters such as variable viscosity parameter β_1, the thermal diffusivity parameter β_2, heat generation parameter c and the Prandtl number Pr on the velocity and temperature profiles, as well as the local skin- friction coefficient and the local Nusselt number are presented in tabular form. Our results suggested that the presence of internal heat generation leads to increase flow than that of without exponentially decaying heat generation term.

Keywords: free convection, heat generation, thermal diffusivity, variable viscosity

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882 Causal Estimation for the Left-Truncation Adjusted Time-Varying Covariates under the Semiparametric Transformation Models of a Survival Time

Authors: Yemane Hailu Fissuh, Zhongzhan Zhang

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In biomedical researches and randomized clinical trials, the most commonly interested outcomes are time-to-event so-called survival data. The importance of robust models in this context is to compare the effect of randomly controlled experimental groups that have a sense of causality. Causal estimation is the scientific concept of comparing the pragmatic effect of treatments conditional to the given covariates rather than assessing the simple association of response and predictors. Hence, the causal effect based semiparametric transformation model was proposed to estimate the effect of treatment with the presence of possibly time-varying covariates. Due to its high flexibility and robustness, the semiparametric transformation model which shall be applied in this paper has been given much more attention for estimation of a causal effect in modeling left-truncated and right censored survival data. Despite its wide applications and popularity in estimating unknown parameters, the maximum likelihood estimation technique is quite complex and burdensome in estimating unknown parameters and unspecified transformation function in the presence of possibly time-varying covariates. Thus, to ease the complexity we proposed the modified estimating equations. After intuitive estimation procedures, the consistency and asymptotic properties of the estimators were derived and the characteristics of the estimators in the finite sample performance of the proposed model were illustrated via simulation studies and Stanford heart transplant real data example. To sum up the study, the bias of covariates was adjusted via estimating the density function for truncation variable which was also incorporated in the model as a covariate in order to relax the independence assumption of failure time and truncation time. Moreover, the expectation-maximization (EM) algorithm was described for the estimation of iterative unknown parameters and unspecified transformation function. In addition, the causal effect was derived by the ratio of the cumulative hazard function of active and passive experiments after adjusting for bias raised in the model due to the truncation variable.

Keywords: causal estimation, EM algorithm, semiparametric transformation models, time-to-event outcomes, time-varying covariate

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881 Spatiotemporal Evaluation of Climate Bulk Materials Production in Atmospheric Aerosol Loading

Authors: Mehri Sadat Alavinasab Ashgezari, Gholam Reza Nabi Bidhendi, Fatemeh Sadat Alavinasab Ashkezari

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Atmospheric aerosol loading (AAL) from anthropogenic sources is an evidence in industrial development. The accelerated trends in material consumption at the global scale in recent years demonstrate consumption paradigms sensible to the planetary boundaries (PB). This paper is a statistical approach on recognizing the path of climate-relevant bulk materials production (CBMP) of steel, cement and plastics to AAL via an updated and validated spatiotemporal distribution. The methodology of statistical analysis used the most updated regional or global databases or instrumental technologies. This corresponded to a selection of processes and areas capable for tracking AAL within the last decade, analyzing the most validated data while leading to explore the behavior functions or models. The results also represented a correlation within socio economic metabolism idea between the materials specified as macronutrients of society and AAL as a PB with an unknown threshold. The selected country contributors of China, India, US and the sample country of Iran show comparable cumulative AAL values vs to the bulk materials domestic extraction and production rate in the study period of 2012 to 2022. Generally, there is a tendency towards gradual descend in the worldwide and regional aerosol concentration after 2015. As of our evaluation, a considerable share of human role, equivalent 20% from CBMP, is for the main anthropogenic species of aerosols, including sulfate, black carbon and organic particulate matters too. This study, in an innovative approach, also explores the potential role of AAL control mechanisms from the economy sectors where ordered and smoothing loading trends are accredited through the disordered phenomena of CBMP and aerosol precursor emissions. The equilibrium states envisioned is an approval to the well-established theory of Spin Glasses applicable in physical system like the Earth and here to AAL.

Keywords: atmospheric aeroso loading, material flows, climate bulk materials, industrial ecology

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880 Ceramic Membrane Filtration Technologies for Oilfield Produced Water Treatment

Authors: Mehrdad Ebrahimi, Oliver Schmitz, Axel Schmidt, Peter Czermak

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“Produced water” (PW) is any fossil water that is brought to the surface along with crude oil or natural gas. By far, PW is the largest waste stream by volume associated with oil and gas production operations. Due to the increasing volume of waste all over the world in the current decade, the outcome and effect of discharging PW on the environment has lately become a significant issue of environmental concerns. Therefore, there is a need for new technologies for PW treatment due to increase focus on water conservation and environmental regulation. The use of membrane processes for treatment of PW has several advantages over many of the traditional separation techniques. In oilfield produced water treatment with ceramic membranes, process efficiency is characterized by the specific permeate flux and by the oil separation performance. Apart from the membrane properties, the permeate flux during filtration of oily wastewaters is known to be strongly dependent on the constituents of the feed solution, as well as on process conditions, e.g. trans-membrane pressure (TMP) and cross-flow velocity (CFV). The research project presented in these report describes the application of different ceramic membrane filtration technologies for the efficient treatment of oil-field produced water and different model oily solutions.

Keywords: ceramic membrane, membrane fouling, oil rejection, produced water treatment

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879 Functional Neural Network for Decision Processing: A Racing Network of Programmable Neurons Where the Operating Model Is the Network Itself

Authors: Frederic Jumelle, Kelvin So, Didan Deng

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In this paper, we are introducing a model of artificial general intelligence (AGI), the functional neural network (FNN), for modeling human decision-making processes. The FNN is composed of multiple artificial mirror neurons (AMN) racing in the network. Each AMN has a similar structure programmed independently by the users and composed of an intention wheel, a motor core, and a sensory core racing at a specific velocity. The mathematics of the node’s formulation and the racing mechanism of multiple nodes in the network will be discussed, and the group decision process with fuzzy logic and the transformation of these conceptual methods into practical methods of simulation and in operations will be developed. Eventually, we will describe some possible future research directions in the fields of finance, education, and medicine, including the opportunity to design an intelligent learning agent with application in AGI. We believe that FNN has a promising potential to transform the way we can compute decision-making and lead to a new generation of AI chips for seamless human-machine interactions (HMI).

Keywords: neural computing, human machine interation, artificial general intelligence, decision processing

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878 Rising of Single and Double Bubbles during Boiling and Effect of Electric Field in This Process

Authors: Masoud Gholam Ale Mohammad, Mojtaba Hafezi Birgani

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An experimental study of saturated pool boiling on a single artificial nucleation site without and with the application of an electric field on the boiling surface has been conducted. N-pentane is boiling on a copper surface and is recorded with a high speed camera providing high quality pictures and movies. The accuracy of the visualization allowed establishing an experimental bubble growth law from a large number of experiments. This law shows that the evaporation rate is decreasing during the bubble growth, and underlines the importance of liquid motion induced by the preceding bubble. Bubble rise is therefore studied: once detached, bubbles accelerate vertically until reaching a maximum velocity in good agreement with a correlation from literature. The bubbles then turn to another direction. The effect of applying an electric field on the boiling surface in finally studied. In addition to changes in the bubble shape, changes are also shown in the liquid plume and the convective structures above the surface. Lower maximum rising velocities were measured in the presence of electric fields, especially with a negative polarity.

Keywords: single and double bubbles, electric field, boiling, rising

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877 Stresses Induced in Saturated Asphalt Pavement by Moving Loads

Authors: Yang Zhong, Meijie Xue

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The purpose of this paper is to investigate the stresses and excess pore fluid pressure induced by the moving wheel pressure on saturated asphalt pavements, which is one of the reasons for a damage phenomenon in flexible pavement denoted stripping. The saturated asphalt pavement is modeled as multilayered poroelastic half space exerted by a wheel pressure, which is moving at a constant velocity along the surface of the pavement. The governing equations for the proposed analysis are based on the Biot’s theory of dynamics in saturated poroelastic medium. The governing partial differential equations are solved by using Laplace and Hankel integral transforms. The solutions for the stresses and excess pore pressure are expressed in the forms of numerical inversion Laplace and Hankel integral transforms. The numerical simulation results clearly demonstrate the induced deformation and water flow in the asphalt pavement.

Keywords: saturated asphalt pavements, moving loads, excess pore fluid pressure, stress of pavement, biot theory, stress and strain of pavement

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876 Numerical Analysis of Laminar Flow around Square Cylinders with EHD Phenomenon

Authors: M. Salmanpour, O. Nourani Zonouz

Abstract:

In this research, a numerical simulation of an Electrohydrodynamic (EHD) actuator’s effects on the flow around a square cylinder by using a finite volume method has been investigated. This is one of the newest ways for controlling the fluid flows. Two plate electrodes are flush-mounted on the surface of the cylinder and one wire electrode is placed on the line with zero angle of attack relative to the stagnation point and excited with DC power supply. The discharge produces an electric force and changes the local momentum behaviors in the fluid layers. For this purpose, after selecting proper domain and boundary conditions, the electric field relating to the problem has been analyzed and then the results in the form of electrical body force have been entered in the governing equations of fluid field (Navier-Stokes equations). The effect of ionic wind resulted from the Electrohydrodynamic actuator, on the velocity, pressure and the wake behind cylinder has been considered. According to the results, it is observed that the fluid flow accelerates in the nearest wall of the frontal half of the cylinder and the pressure difference between frontal and hinder cylinder is increased.

Keywords: CFD, corona discharge, electro hydrodynamics, flow around square cylinders, simulation

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875 Assessing the Prevalence of Accidental Iatrogenic Paracetamol Overdose in Adult Hospital Patients Weighing <50kg: A Quality Improvement Project

Authors: Elisavet Arsenaki

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Paracetamol overdose is associated with significant and possibly permanent consequences including hepatotoxicity, acute and chronic liver failure, and death. This quality improvement project explores the prevalence of accidental iatrogenic paracetamol overdose in hospital patients with a low body weight, defined as <50kg and assesses the impact of educational posters in trying to reduce it. The study included all adult inpatients on the admissions ward, a short stay ward for patients requiring 12-72 hour treatment, and consisted of three cycles. Each cycle consisted of 3 days of data collection in a given month (data collection for cycle 1 occurred in January 2022, February 2022 for cycle 2 and March 2022 for cycle 3). All patients given paracetamol had their prescribed dose checked against their charted weight to identify the percentage of adult inpatients <50kg who were prescribed 1g of paracetamol instead of 500mg. In the first cycle of the audit, data were collected from 83 patients who were prescribed paracetamol on the admissions ward. Subsequently, four A4 educational posters were displayed across the ward, on two separate occasions and with a one-month interval in between each poster display. The aim of this was to remind prescribing doctors of their responsibility to check patient body weight prior to prescribing paracetamol. Data were collected again one week after each round of poster display, from 72 and 70 patients respectively. Over the 3 cycles with a cumulative 225 patients, 15 weighed <50kg (6.67%) and of those, 5 were incorrectly prescribed 1g of paracetamol, yielding a 33.3% prevalence of accidental iatrogenic paracetamol overdose in adult inpatients. In cycle 1 of the project, 3 out of 6 adult patients weighing <50kg were overdosed on paracetamol, meaning that 50% of low weight patients were prescribed the wrong dose of paracetamol for their weight. In the second data collection cycle, 1 out of 5 <50kg patients were overdosed (20%) and in the third cycle, 1 out of 4 (25%). The use of educational posters resulted in a lower prevalence of accidental iatrogenic paracetamol overdose in low body weight adult inpatients. However, the differences observed were statistically insignificant (p value 0.993 and 0.995 respectively). Educational posters did not induce a significant decrease in the prevalence of accidental iatrogenic paracetamol overdose. More robust strategies need to be employed to further decrease paracetamol overdose in patients weighing <50kg.

Keywords: iatrogenic, overdose, paracetamol, patient, safety

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874 The Effects of Damping Devices on Displacements, Velocities and Accelerations of Structures

Authors: Radhwane Boudjelthia

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The most recent earthquakes occurred in the world have killed thousands of people and severe damage. For all the actors involved in the building process, the earthquake is the litmus test for construction. The goal we set ourselves is to contribute to the implementation of a thoughtful approach to the seismic protection of structures. For many engineers, the most conventional approach to protection works (buildings and bridges) the effects of earthquakes is to increase rigidity. This approach is not always effective, especially when there is a context that favors the phenomenon of resonance and amplification of seismic forces. Therefore, the field of earthquake engineering has made significant inroads, among others catalyzed by the development of computational techniques in computer form and the use of powerful test facilities. This has led to the emergence of several innovative technologies, such as the introduction of special devices insulation between infrastructure and superstructure. This approach, commonly known as "seismic isolation," to absorb the significant efforts without the structure is damaged and thus ensuring the protection of lives and property. In addition, the restraints to the construction by the ground shaking are located mainly at the supports. With these moves, the natural period of construction is increasing, and seismic loads are reduced. Thus, there is an attenuation of the seismic movement. Likewise, the insulation of the base mechanism may be used in combination with earthquake dampers in order to control the deformation of the insulation system and the absolute displacement of the superstructure located above the isolation interface. On the other hand, only can use these earthquake dampers to reduce the oscillation amplitudes and thus reduce seismic loads. The use of damping devices represents an effective solution for the rehabilitation of existing structures. Given all these acceleration reducing means considered passive, much research has been conducted for several years to develop an active control system of the response of buildings to earthquakes.

Keywords: earthquake, building, seismic forces, displacement, resonance, response.

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873 Thermal Analysis for Darcy Forchheimer Effect with Hybrid Ferro Fluid Flow

Authors: Behzad Ali Khan, M. Zubair Akbar Qureshi

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

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

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872 Advance Hybrid Manufacturing Supply Chain System to Get Benefits of Push and Pull Systems

Authors: Akhtar Nawaz, Sahar Noor, Iftikhar Hussain

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This paper considers advanced hybrid manufacturing planning both push and pull system in which each customer order has a due date by demand forecast and customer orders. We present a tool for model for tool development that requires an absolute due dates and customer orders in a manufacturing supply chain. It is vital for the manufacturing companies to face the problem of variations in demands, increase in varieties by maintaining safety stock and to minimize components obsolescence and uselessness. High inventory cost and low delivery lead time is expected in push type of system and on contrary high delivery lead time and low inventory cost is predicted in the pull type. For this tool for model we need an MRP system for the push and pull environment and control of inventories in push parts and lead time in the pull part. To retain process data quickly, completely and to improve responsiveness and minimize inventory cost, a tool is required to deal with the high product variance and short cycle parts. In practice, planning and scheduling are interrelated and should be solved simultaneously with supply chain to ensure that the due dates of customer orders are met. The proposed tool for model considers alternative process plans for job types, with precedence constraints for job operations. Such a tool for model has not been treated in the literature. To solve the model, tool was developed, so a new technique was required to deal with the issue of high product variance and short life cycles in assemble to order.

Keywords: hybrid manufacturing system, supply chain system, make to order, make to stock, assemble to order

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871 Shock Response Analysis of Soil-Structure Systems Induced by Near-Fault Pulses

Authors: H. Masaeli, R. Ziaei, F. Khoshnoudian

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Shock response analysis of the soil–structure systems induced by near–fault pulses is investigated. Vibration transmissibility of the soil–structure systems is evaluated by Shock Response Spectra (SRS). Medium–to–high rise buildings with different aspect ratios located on different soil types as well as different foundations with respect to vertical load bearing safety factors are studied. Two types of mathematical near–fault pulses, i.e. forward directivity and fling step, with different pulse periods as well as pulse amplitudes are selected as incident ground shock. Linear versus nonlinear Soil–Structure Interaction (SSI) condition are considered alternatively and the corresponding results are compared. The results show that nonlinear SSI is likely to amplify the acceleration responses when subjected to long–period incident pulses with normalized period exceeding a threshold. It is also shown that this threshold correlates with soil type, so that increased shear–wave velocity of the underlying soil makes the threshold period decrease.

Keywords: nonlinear soil–structure interaction, shock response spectrum, near–fault ground shock, rocking isolation

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870 Posttraumatic Stress and Comorbid Emotional and Behavioral Problems in Sri Lankan Adolescents

Authors: Thyagi Ponnamperuma

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Background: Comorbidity between posttraumatic stress disorder (PTSD) and other psychological problems is common. Recent studies focused to investigate the underlying relationship between PTSD and comorbid psychopathologies. Among adolescents, higher rates of emotional and behavioral problems (EBP) have been reported following trauma, often coexisted with PTSD. The current study, thus, examined the relationship of posttraumatic stress symptoms to EBP in adolescents exposed to a variety of traumatic events. Further, the study investigated the relationship of trauma and comorbid PTSS to the self-perceived negative impact of EBP on daily functioning. Methods: Participants were 729 Sri Lankan adolescents (age 12 to 16 years; 54.9% female) living in areas impacted in varying degrees by the 2004 tsunami. In 2008, school-based screening was conducted and completed measures of, trauma exposure, PTSS, EBP, and related functional impairment. Results: Participants reported a high prevalence of trauma exposure (n = 438), including interpersonal violence (n = 155). DSM-IV criteria for full or partial PTSD were met by 23.7% of the trauma-exposed sample. Across all participants, 13.4% and 16.7% displayed clinically relevant levels of EBP and functional impairment, respectively. Among the trauma-exposed, 7% met criteria for both EBP and PTSD. EBP total scores and caseness were significantly higher in trauma-exposed adolescents with PTSD than in either those without PTSD or the non-traumatized control group. In subscale analysis, higher prevalence of serious emotional, conduct, and hyperactivity problems were reported in the PTSD positive group; the PTSD negative group did not differ significantly from the control group on any of the problem scales. In regression analyses, PTSS (β = .28, p < .001) and interpersonal violence (β = .13, p = .033) were significant predictors of EBP, cumulative trauma (β = .11, p = .076) showed no significant effect. Further, PTSS exacerbated the impact of EBP on daily functioning (β = 0.29, p = .023). Conclusion: PTSS were closely linked to EBP in adolescents, even years after the traumatic experience. PTSD and emotional and behavioral problems together pose a heightened risk for impaired daily functioning. Longitudinal studies are needed to clarify the causal pathway.

Keywords: adolescents, comorbidity, emotional and behavioral problems, functional impairment, posttraumatic stress, traumatic events

Procedia PDF Downloads 173