Search results for: hierarchical structure model
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 22625

Search results for: hierarchical structure model

19865 An Outsourcing System Model for the Thai Electrical Appliances Industry

Authors: Sudawan Somjai

Abstract:

The purpose of this paper was to find an appropriate outsourcing system model for the Thai electrical appliances industry. The objective was to increase competitive capability of the industry with an outsourcing system. The population for this study was the staff in the selected 10 companies in Thai electrical appliances industry located in Bangkok and the eastern part of Thailand. Data collecting techniques included in-depth interviews, focus group and storytelling techniques. The data was collected from 5 key informants from each company, making a total of 50 informants. The findings revealed that an outsourcing model would consist of important factors including outsourcing system, labor flexibility, capability of business process, manpower management efficiency, cost reduction, business risk elimination, core competency and competitiveness. Different suggestions were made as well in this research paper.

Keywords: outsourcing system, model, Thailand, electrical appliances industry

Procedia PDF Downloads 579
19864 Governance Framework for an Emerging Trust Ecosystem with a Blockchain-Based Supply Chain

Authors: Ismael Ávila, José Reynaldo F. Filho, Vasco Varanda Picchi

Abstract:

The ever-growing consumer awareness of food provenance in Brazil is driving the creation of a trusted ecosystem around the animal protein supply chain. The traceability and accountability requirements of such an ecosystem demand a blockchain layer to strengthen the weak links in that chain. For that, direct involvement of the companies in the blockchain transactions, including as validator nodes of the network, implies formalizing a partnership with the consortium behind the ecosystem. Yet, their compliance standards usually require that a formal governance structure is in place before they agree with any membership terms. In light of such a strategic role of blockchain governance, the paper discusses a framework for tailoring a governance model for a blockchain-based solution aimed at the meat supply chain and evaluates principles and attributes in terms of their relevance to the development of a robust trust ecosystem.

Keywords: blockchain, governance, trust ecosystem, supply chain, traceability

Procedia PDF Downloads 101
19863 Adaptive Kaman Filter for Fault Diagnosis of Linear Parameter-Varying Systems

Authors: Rajamani Doraiswami, Lahouari Cheded

Abstract:

Fault diagnosis of Linear Parameter-Varying (LPV) system using an adaptive Kalman filter is proposed. The LPV model is comprised of scheduling parameters, and the emulator parameters. The scheduling parameters are chosen such that they are capable of tracking variations in the system model as a result of changes in the operating regimes. The emulator parameters, on the other hand, simulate variations in the subsystems during the identification phase and have negligible effect during the operational phase. The nominal model and the influence vectors, which are the gradient of the feature vector respect to the emulator parameters, are identified off-line from a number of emulator parameter perturbed experiments. A Kalman filter is designed using the identified nominal model. As the system varies, the Kalman filter model is adapted using the scheduling variables. The residual is employed for fault diagnosis. The proposed scheme is successfully evaluated on simulated system as well as on a physical process control system.

Keywords: identification, linear parameter-varying systems, least-squares estimation, fault diagnosis, Kalman filter, emulators

Procedia PDF Downloads 487
19862 A Consideration on the Offset Frontal Impact Modeling Using Spring-Mass Model

Authors: Jaemoon Lim

Abstract:

To construct the lumped spring-mass model considering the occupants for the offset frontal crash, the SISAME software and the NHTSA test data were used. The data on 56 kph 40% offset frontal vehicle to deformable barrier crash test of a MY2007 Mazda 6 4-door sedan were obtained from NHTSA test database. The overall behaviors of B-pillar and engine of simulation models agreed very well with the test data. The trends of accelerations at the driver and passenger head were similar but big differences in peak values. The differences of peak values caused the large errors of the HIC36 and 3 ms chest g’s. To predict well the behaviors of dummies, the spring-mass model for the offset frontal crash needs to be improved.

Keywords: chest g’s, HIC36, lumped spring-mass model, offset frontal impact, SISAME

Procedia PDF Downloads 442
19861 Factors Influencing the Roles and Responsibilities of Middle Leaders in Saudi and English Primary Schools: A Comparative Critical Study

Authors: Saeed Musaid H. Alzahrani

Abstract:

The role of middle leaders, especially in primary schools, is a multi-faced role that has been subject to changes in nature over recent decades, with claims for more distributed leadership practices. This research examines the way 18 middle leaders in Saudi and English primary schools conceptualise their roles and responsibilities, and different factors influencing those roles and responsibilities. It begins from the premise that both the power of the role and the values of middle leaders are grounded in cultural and political bases, a belief held by the researcher as an 'insider' within the Saudi educational leadership context. The study consisted of a comparative analysis of the role and the responsibilities of middle leaders in Saudi primary schools and their equivalents in English primary schools. A purely qualitative methodological stance was adopted, using in-depth face-to-face semi-structured interviews, observations and document analysis. Middle leaders were asked to reflect deeply on their perceptions and understanding of their roles and explain what they thought influenced their daily practices and responsibilities. The findings suggest that the concept of middle leadership has been influenced by power imposed from above by political authority, via internal and external hierarchical structures, which shapes the nature of the role of the middle leaders and forces them to comply. Middle leaders seem to believe they have the power to make decisions and promote change, but these findings suggest that this is illusory. The power that keeps middle leaders performing is the power of their cultural and religious values. Those values are the resource to which they turn in their search for more energy when they lack support and are short of time taken. Middle leaders in Saudi, just like their equivalents in English schools must comply with the requirements of their role. However, Saudi middle leaders are given no leeway to make decisions or implement change, neither do they have the culture of collegiality that seems to give middle leaders in England more power over their resources and decisions. However, in neither educational setting have middle leaders been given the power to lead, so they remain managers rather than leaders. The findings of this research suggest that there are more similarities between the educational settings of Saudi and England than differences; and in the light of different factors identified in the study, suggest the establishment of a framework for middle leadership, in the hope of enhancing the way the role is practiced.

Keywords: middle leader, primary school, power, educational leadership, value, culture, model, Saudi Arabia, England

Procedia PDF Downloads 182
19860 A Model for Optimizing Inventory Replenishment and Shelf Space Management in Retail Industries

Authors: Nermine A. Harraz, Aliaa Abouali

Abstract:

The retail stores put up for sale multiple items while the spaces in the backroom and display areas constitute a scarce resource. Availability, volume, and location of the product displayed in the showroom influence the customer’s demand. Managing these operations individually will result in sub-optimal overall retail store’s profit; therefore, a non-linear integer programming model (NLIP) is developed to determine the inventory replenishment and shelf space allocation decisions that together maximize the retailer’s profit under shelf space and backroom storage constraints taking into consideration that the demand rate is positively dependent on the amount and location of items displayed in the showroom. The developed model is solved using LINGO® software. The NLIP model is implemented in a real world case study in a large retail outlet providing a large variety of products. The proposed model is validated and shows logical results when using the experimental data collected from the market.

Keywords: retailing management, inventory replenishment, shelf space allocation, showroom, backroom

Procedia PDF Downloads 338
19859 Enhancing Cloud Computing with Security Trust Model

Authors: John Ayoade

Abstract:

Cloud computing is a model that enables the delivery of on-demand computing resources such as networks, servers, storage, applications and services over the internet. Cloud Computing is a relatively growing concept that presents a good number of benefits for its users; however, it also raises some security challenges which may slow down its use. In this paper, we identify some of those security issues that can serve as barriers to realizing the full benefits that cloud computing can bring. One of the key security problems is security trust. A security trust model is proposed that can enhance the confidence that users need to fully trust the use of public and mobile cloud computing and maximize the potential benefits that they offer.

Keywords: cloud computing, trust, security, certificate authority, PKI

Procedia PDF Downloads 467
19858 Marginalized Two-Part Joint Models for Generalized Gamma Family of Distributions

Authors: Mohadeseh Shojaei Shahrokhabadi, Ding-Geng (Din) Chen

Abstract:

Positive continuous outcomes with a substantial number of zero values and incomplete longitudinal follow-up are quite common in medical cost data. To jointly model semi-continuous longitudinal cost data and survival data and to provide marginalized covariate effect estimates, a marginalized two-part joint model (MTJM) has been developed for outcome variables with lognormal distributions. In this paper, we propose MTJM models for outcome variables from a generalized gamma (GG) family of distributions. The GG distribution constitutes a general family that includes approximately all of the most frequently used distributions like the Gamma, Exponential, Weibull, and Log Normal. In the proposed MTJM-GG model, the conditional mean from a conventional two-part model with a three-parameter GG distribution is parameterized to provide the marginal interpretation for regression coefficients. In addition, MTJM-gamma and MTJM-Weibull are developed as special cases of MTJM-GG. To illustrate the applicability of the MTJM-GG, we applied the model to a set of real electronic health record data recently collected in Iran, and we provided SAS code for application. The simulation results showed that when the outcome distribution is unknown or misspecified, which is usually the case in real data sets, the MTJM-GG consistently outperforms other models. The GG family of distribution facilitates estimating a model with improved fit over the MTJM-gamma, standard Weibull, or Log-Normal distributions.

Keywords: marginalized two-part model, zero-inflated, right-skewed, semi-continuous, generalized gamma

Procedia PDF Downloads 162
19857 Biochemical Characterization and Structure Elucidation of a New Cytochrome P450 Decarboxylase

Authors: Leticia Leandro Rade, Amanda Silva de Sousa, Suman Das, Wesley Generoso, Mayara Chagas Ávila, Plinio Salmazo Vieira, Antonio Bonomi, Gabriela Persinoti, Mario Tyago Murakami, Thomas Michael Makris, Leticia Maria Zanphorlin

Abstract:

Alkenes have an economic appeal, especially in the biofuels field, since they are precursors for drop-in biofuels production, which have similar chemical and physical properties to the conventional fossil fuels, with no oxygen in their composition. After the discovery of the first P450 CYP152 OleTJE in 2011, reported with its unique property of decarboxylating fatty acids (FA), by using hydrogen peroxide as a cofactor and producing 1-alkenes as the main product, the scientific and technological interest in this family of enzymes vastly increased. In this context, the present work presents a new decarboxylase (OleTRN) with low similarity with OleTJE (32%), its biochemical characterization, and structure elucidation. As main results, OleTRN presented a high yield of expression and purity, optimum reaction conditions at 35 °C and pH from 6.5 to 8.0, and higher specificity for oleic acid. Besides that, structure-guided mutations were performed and according to the functional characterizations, it was observed that some mutations presented different specificity and chemoselectivity by varying the chain-length of FA substrates from 12 to 20 carbons. These results are extremely interesting from a biotechnological perspective as those characteristics could diversify the applications and contribute to designing better cytochrome P450 decarboxylases. Considering that peroxygenases have the potential activity of decarboxylating and hydroxylating fatty acids and that the elucidation of the intriguing mechanistic involved in the decarboxylation preferential from OleTJE is still a challenge, the elucidation of OleTRN structure and the functional characterizations of OleTRN and its mutants contribute to new information about CYP152. Besides that, the work also contributed to the discovery of a new decarboxylase with a different selectivity profile from OleTJE, which allows a wide range of applications.

Keywords: P450, decarboxylases, alkenes, biofuels

Procedia PDF Downloads 181
19856 Different Sampling Schemes for Semi-Parametric Frailty Model

Authors: Nursel Koyuncu, Nihal Ata Tutkun

Abstract:

Frailty model is a survival model that takes into account the unobserved heterogeneity for exploring the relationship between the survival of an individual and several covariates. In the recent years, proposed survival models become more complex and this feature causes convergence problems especially in large data sets. Therefore selection of sample from these big data sets is very important for estimation of parameters. In sampling literature, some authors have defined new sampling schemes to predict the parameters correctly. For this aim, we try to see the effect of sampling design in semi-parametric frailty model. We conducted a simulation study in R programme to estimate the parameters of semi-parametric frailty model for different sample sizes, censoring rates under classical simple random sampling and ranked set sampling schemes. In the simulation study, we used data set recording 17260 male Civil Servants aged 40–64 years with complete 10-year follow-up as population. Time to death from coronary heart disease is treated as a survival-time and age, systolic blood pressure are used as covariates. We select the 1000 samples from population using different sampling schemes and estimate the parameters. From the simulation study, we concluded that ranked set sampling design performs better than simple random sampling for each scenario.

Keywords: frailty model, ranked set sampling, efficiency, simple random sampling

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19855 Design of a Tool for Generating Test Cases from BPMN

Authors: Prat Yotyawilai, Taratip Suwannasart

Abstract:

Business Process Model and Notation (BPMN) is more important in the business process and creating functional models, and is a standard for OMG, which becomes popular in various organizations and in education. Researches related to software testing based on models are prominent. Although most researches use the UML model in software testing, not many researches use the BPMN Model in creating test cases. Therefore, this research proposes a design of a tool for generating test cases from the BPMN. The model is analyzed and the details of the various components are extracted before creating a flow graph. Both details of components and the flow graph are used in generating test cases.

Keywords: software testing, test case, BPMN, flow graph

Procedia PDF Downloads 542
19854 An Approach for Modeling CMOS Gates

Authors: Spyridon Nikolaidis

Abstract:

A modeling approach for CMOS gates is presented based on the use of the equivalent inverter. A new model for the inverter has been developed using a simplified transistor current model which incorporates the nanoscale effects for the planar technology. Parametric expressions for the output voltage are provided as well as the values of the output and supply current to be compatible with the CCS technology. The model is parametric according the input signal slew, output load, transistor widths, supply voltage, temperature and process. The transistor widths of the equivalent inverter are determined by HSPICE simulations and parametric expressions are developed for that using a fitting procedure. Results for the NAND gate shows that the proposed approach offers sufficient accuracy with an average error in propagation delay about 5%.

Keywords: CMOS gate modeling, inverter modeling, transistor current mode, timing model

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19853 Controlling the Oxygen Vacancies in the Structure of Anode Materials for Improved Electrochemical Performance in Lithium-Ion Batteries

Authors: Moustafa M. S. Sanad

Abstract:

The worsening of energy supply crisis and the exacerbation of climate change by environmental pollution problems have become the greatest threat to human life. One of the ways to confront these problems is to rely on renewable energy and its storage systems. Nowadays, huge attention has been directed to the development of lithium-ion batteries (LIBs) as efficient tools for storing the clean energy produced by green sources like solar and wind energies. Accordingly, the demand for powerful electrode materials with excellent electrochemical characteristics has been progressively increased to meet fast and continuous growth in the market of energy storage systems. Therefore, the electronic and electrical properties of conversion anode materials for rechargeable lithium-ion batteries (LIBs) can be enhanced by introducing lattice defects and oxygen vacancies in the crystal structure. In this regard, the intended presentation will demonstrate new insights and effective ways for enhancing the electrical conductivity and improving the electrochemical performance of different anode materials such as MgFe₂O₄, CdFe₂O₄, Fe₃O₄, LiNbO₃ and Nb₂O₅. The changes in the physicochemical and morphological properties have been deeply investigated via structural and spectroscopic analyses (e.g., XRD, FESEM, HRTEM, and XPS). Moreover, the enhancement in the electrochemical properties of these anode materials will be discussed through Galvanostatic Cycling (GC), Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS) techniques.

Keywords: structure modification, cationic substitution, non-stoichiometric synthesis, plasma treatment, lithium-ion batteries

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19852 Two-Stage Launch Vehicle Trajectory Modeling for Low Earth Orbit Applications

Authors: Assem M. F. Sallam, Ah. El-S. Makled

Abstract:

This paper presents a study on the trajectory of a two stage launch vehicle. The study includes dynamic responses of motion parameters as well as the variation of angles affecting the orientation of the launch vehicle (LV). LV dynamic characteristics including state vector variation with corresponding altitude and velocity for the different LV stages separation, as well as the angle of attack and flight path angles are also discussed. A flight trajectory study for the drop zone of first stage and the jettisoning of fairing are introduced in the mathematical modeling to study their effect. To increase the accuracy of the LV model, atmospheric model is used taking into consideration geographical location and the values of solar flux related to the date and time of launch, accurate atmospheric model leads to enhancement of the calculation of Mach number, which affects the drag force over the LV. The mathematical model is implemented on MATLAB based software (Simulink). The real available experimental data are compared with results obtained from the theoretical computation model. The comparison shows good agreement, which proves the validity of the developed simulation model; the maximum error noticed was generally less than 10%, which is a result that can lead to future works and enhancement to decrease this level of error.

Keywords: launch vehicle modeling, launch vehicle trajectory, mathematical modeling, Matlab- Simulink

Procedia PDF Downloads 266
19851 Impact of Air Flow Structure on Distinct Shape of Differential Pressure Devices

Authors: A. Bertašienė

Abstract:

Energy harvesting from any structure makes a challenge. Different structure of air/wind flows in industrial, environmental and residential applications emerge the real flow investigation in detail. Many of the application fields are hardly achievable to the detailed description due to the lack of up-to-date statistical data analysis. In situ measurements aim crucial investments thus the simulation methods come to implement structural analysis of the flows. Different configurations of testing environment give an overview how important is the simple structure of field in limited area on efficiency of the system operation and the energy output. Several configurations of modeled working sections in air flow test facility was implemented in CFD ANSYS environment to compare experimentally and numerically air flow development stages and forms that make effects on efficiency of devices and processes. Effective form and amount of these flows under different geometry cases define the manner of instruments/devices that measure fluid flow parameters for effective operation of any system and emission flows to define. Different fluid flow regimes were examined to show the impact of fluctuations on the development of the whole volume of the flow in specific environment. The obtained results rise the discussion on how these simulated flow fields are similar to real application ones. Experimental results have some discrepancies from simulation ones due to the models implemented to fluid flow analysis in initial stage, not developed one and due to the difficulties of models to cover transitional regimes. Recommendations are essential for energy harvesting systems in both, indoor and outdoor cases. Further investigations aim to be shifted to experimental analysis of flow under laboratory conditions using state-of-the-art techniques as flow visualization tool and later on to in situ situations that is complicated, cost and time consuming study.

Keywords: fluid flow, initial region, tube coefficient, distinct shape

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19850 Calibration and Validation of the Aquacrop Model for Simulating Growth and Yield of Rain-Fed Sesame (Sesamum Indicum L.) Under Different Soil Fertility Levels in the Semi-arid Areas of Tigray, Ethiopia

Authors: Abadi Berhane, Walelign Worku, Berhanu Abrha, Gebre Hadgu

Abstract:

Sesame is an important oilseed crop in Ethiopia, which is the second most exported agricultural commodity next to coffee. However, there is poor soil fertility management and a research-led farming system for the crop. The AquaCrop model was applied as a decision-support tool, which performs a semi-quantitative approach to simulate the yield of crops under different soil fertility levels. The objective of this experiment was to calibrate and validate the AquaCrop model for simulating the growth and yield of sesame under different nitrogen fertilizer levels and to test the performance of the model as a decision-support tool for improved sesame cultivation in the study area. The experiment was laid out as a randomized complete block design (RCBD) in a factorial arrangement in the 2016, 2017, and 2018 main cropping seasons. In this experiment, four nitrogen fertilizer rates, 0, 23, 46, and 69 Kg/ha nitrogen, and three improved varieties (Setit-1, Setit-2, and Humera-1). In the meantime, growth, yield, and yield components of sesame were collected from each treatment. Coefficient of determination (R2), Root mean square error (RMSE), Normalized root mean square error (N-RMSE), Model efficiency (E), and Degree of agreement (D) were used to test the performance of the model. The results indicated that the AquaCrop model successfully simulated soil water content with R2 varying from 0.92 to 0.98, RMSE 6.5 to 13.9 mm, E 0.78 to 0.94, and D 0.95 to 0.99, and the corresponding values for AB also varied from 0.92 to 0.98, 0.33 to 0.54 tons/ha, 0.74 to 0.93, and 0.9 to 0.98, respectively. The results on the canopy cover of sesame also showed that the model acceptably simulated canopy cover with R2 varying from 0.95 to 0.99 and a RMSE of 5.3 to 8.6%. The AquaCrop model was appropriately calibrated to simulate soil water content, canopy cover, aboveground biomass, and sesame yield; the results indicated that the model adequately simulated the growth and yield of sesame under the different nitrogen fertilizer levels. The AquaCrop model might be an important tool for improved soil fertility management and yield enhancement strategies of sesame. Hence, the model might be applied as a decision-support tool in soil fertility management in sesame production.

Keywords: aquacrop model, normalized water productivity, nitrogen fertilizer, canopy cover, sesame

Procedia PDF Downloads 55
19849 Nanomechanical Devices Vibrating at Microwave Frequencies in Simple Liquids

Authors: Debadi Chakraborty, John E. Sader

Abstract:

Nanomechanical devices have emerged as a versatile platform for a host of applications due to their extreme sensitivity to environmental conditions. For example, mass measurements with sensitivity at the atomic level have recently been demonstrated. Ultrafast laser spectroscopy coherently excite the vibrational modes of metal nanoparticles and permits precise measurement of the vibration characteristics as a function of nanoparticle shape, size and surrounding environment. This study reports that the vibration of metal nanoparticles in simple liquids, like water and glycerol are not described by conventional fluid mechanics, i.e., Navier Stokes equations. The intrinsic molecular relaxation processes in the surrounding liquid are found to have a profound effect on the fluid-structure interaction of mechanical devices at nanometre scales. Theoretical models have been developed based on the non-Newtonian viscoelastic fluid-structure interaction theory to investigate the vibration of nanoparticles immersed in simple fluids. The utility of this theoretical framework is demonstrated by comparison to measurements on single nanowires and ensembles of metal rods. This study provides a rigorous foundation for the use of metal nanoparticles as ultrasensitive mechanical sensors in fluid and opens a new paradigm for understanding extremely high frequency fluid mechanics, nanoscale sensing technologies, and biophysical processes.

Keywords: fluid-structure interaction, nanoparticle vibration, ultrafast laser spectroscopy, viscoelastic damping

Procedia PDF Downloads 258
19848 Crack Growth Life Prediction of a Fighter Aircraft Wing Splice Joint Under Spectrum Loading Using Random Forest Regression and Artificial Neural Networks with Hyperparameter Optimization

Authors: Zafer Yüce, Paşa Yayla, Alev Taşkın

Abstract:

There are heaps of analytical methods to estimate the crack growth life of a component. Soft computing methods have an increasing trend in predicting fatigue life. Their ability to build complex relationships and capability to handle huge amounts of data are motivating researchers and industry professionals to employ them for challenging problems. This study focuses on soft computing methods, especially random forest regressors and artificial neural networks with hyperparameter optimization algorithms such as grid search and random grid search, to estimate the crack growth life of an aircraft wing splice joint under variable amplitude loading. TensorFlow and Scikit-learn libraries of Python are used to build the machine learning models for this study. The material considered in this work is 7050-T7451 aluminum, which is commonly preferred as a structural element in the aerospace industry, and regarding the crack type; corner crack is used. A finite element model is built for the joint to calculate fastener loads and stresses on the structure. Since finite element model results are validated with analytical calculations, findings of the finite element model are fed to AFGROW software to calculate analytical crack growth lives. Based on Fighter Aircraft Loading Standard for Fatigue (FALSTAFF), 90 unique fatigue loading spectra are developed for various load levels, and then, these spectrums are utilized as inputs to the artificial neural network and random forest regression models for predicting crack growth life. Finally, the crack growth life predictions of the machine learning models are compared with analytical calculations. According to the findings, a good correlation is observed between analytical and predicted crack growth lives.

Keywords: aircraft, fatigue, joint, life, optimization, prediction.

Procedia PDF Downloads 154
19847 Wind Energy Loss Phenomenon Over Volumized Building Envelope with Porous Air Portals

Authors: Ying-chang Yu, Yuan-lung Lo

Abstract:

More and more building envelopes consist of the construction of balconies, canopies, handrails, sun-shading, vertical planters or gardens, maintenance platforms, display devices, lightings, ornaments, and also the most commonly seen double skin system. These components form a uniform but three-dimensional disturbance structure and create a complex surface wind field in front of the actual watertight building interface. The distorted wind behavior would affect the façade performance and building ventilation. Comparing with sole windscreen walls, these three-dimensional structures perform like distributed air portal assembly, and each portal generates air turbulence and consume wind pressure and energy simultaneously. In this study, we attempted to compare the behavior of 2D porous windscreens without internal construction, porous tubular portal windscreens, porous tapered portal windscreens, and porous coned portal windscreens. The wind energy reduction phenomenon is then compared to the different distributed air portals. The experiments are conducted in a physical wind tunnel with 1:25 in scale to simulate the three-dimensional structure of a real building envelope. The experimental airflow was set up to smooth flow. The specimen is designed as a plane with a distributed tubular structure behind, and the control group uses different tubular shapes but the same fluid volume to observe the wind damping phenomenon of various geometries.

Keywords: volumized building envelope, porous air portal, wind damping, wind tunnel test, wind energy loss

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19846 Physical Characterization of a Watershed for Correlation with Parameters of Thomas Hydrological Model and Its Application in Iber Hidrodinamic Model

Authors: Carlos Caro, Ernest Blade, Nestor Rojas

Abstract:

This study determined the relationship between basic geo-technical parameters and parameters of the hydro logical model Thomas for water balance of rural watersheds, as a methodological calibration application, applicable in distributed models as IBER model, which represents a distributed system simulation models for unsteady flow numerical free surface. There was an exploration in 25 points (on 15 sub) basin of Rio Piedras (Boy.) obtaining soil samples, to which geo-technical characterization was performed by laboratory tests. Thomas model has a physical characterization of the input area by only four parameters (a, b, c, d). Achieve measurable relationship between geo technical parameters and 4 values of hydro logical parameters helps to determine subsurface, underground and surface flow more agile manner. It is intended in this way to reach some solutions regarding limits initial model parameters on the basis of Thomas geo-technical characterization. In hydro geological models of rural watersheds, calibration is an important process in the characterization of the study area. This step can require a significant computational cost and time, especially if the initial values or parameters before calibration are outside of the geo-technical reality. A better approach in these initial values means optimization of these process through a geo-technical materials area, where is obtained an important approach to the study as in the starting range of variation for the calibration parameters.

Keywords: distributed hydrology, hydrological and geotechnical characterization, Iber model

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19845 Diachronic Evolution and Multifaceted Interpretation of City-Mountain Landscape Culture: From Ritualistic Divinity to Poetic Aesthetics

Authors: Junjie Fu

Abstract:

This paper explores the cultural evolution of the "city-mountain" landscape in ancient Chinese cities, tracing its origins in the regional mountain and town division within the national system. It delves into the cultural archetype of "city-mountain" landscape divine imagery and its spatial characteristics, drawing from the spatial conception of mountain worship and divine order in the model of Kunlun and Penglai. Furthermore, it examines the shift from religious to daily life influences, leading to a poetic aesthetic turn in the "city-mountain" landscape. The paper also discusses the organizational structure of the "city-mountain" poetic landscape and its role as a space for enjoyment. By studying the cultural connotations, evolving relationships, and power mechanisms of the "city-mountain" landscape, this research provides theoretical insights for the construction and development of "city-mountain" landscapes and mountain cities.

Keywords: city-mountain landscape, cultural image, divinity, landscape image, poetry

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19844 Model Predictive Control with Unscented Kalman Filter for Nonlinear Implicit Systems

Authors: Takashi Shimizu, Tomoaki Hashimoto

Abstract:

A class of implicit systems is known as a more generalized class of systems than a class of explicit systems. To establish a control method for such a generalized class of systems, we adopt model predictive control method which is a kind of optimal feedback control with a performance index that has a moving initial time and terminal time. However, model predictive control method is inapplicable to systems whose all state variables are not exactly known. In other words, model predictive control method is inapplicable to systems with limited measurable states. In fact, it is usual that the state variables of systems are measured through outputs, hence, only limited parts of them can be used directly. It is also usual that output signals are disturbed by process and sensor noises. Hence, it is important to establish a state estimation method for nonlinear implicit systems with taking the process noise and sensor noise into consideration. To this purpose, we apply the model predictive control method and unscented Kalman filter for solving the optimization and estimation problems of nonlinear implicit systems, respectively. The objective of this study is to establish a model predictive control with unscented Kalman filter for nonlinear implicit systems.

Keywords: optimal control, nonlinear systems, state estimation, Kalman filter

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19843 Deep Routing Strategy: Deep Learning based Intelligent Routing in Software Defined Internet of Things.

Authors: Zabeehullah, Fahim Arif, Yawar Abbas

Abstract:

Software Defined Network (SDN) is a next genera-tion networking model which simplifies the traditional network complexities and improve the utilization of constrained resources. Currently, most of the SDN based Internet of Things(IoT) environments use traditional network routing strategies which work on the basis of max or min metric value. However, IoT network heterogeneity, dynamic traffic flow and complexity demands intelligent and self-adaptive routing algorithms because traditional routing algorithms lack the self-adaptions, intelligence and efficient utilization of resources. To some extent, SDN, due its flexibility, and centralized control has managed the IoT complexity and heterogeneity but still Software Defined IoT (SDIoT) lacks intelligence. To address this challenge, we proposed a model called Deep Routing Strategy (DRS) which uses Deep Learning algorithm to perform routing in SDIoT intelligently and efficiently. Our model uses real-time traffic for training and learning. Results demonstrate that proposed model has achieved high accuracy and low packet loss rate during path selection. Proposed model has also outperformed benchmark routing algorithm (OSPF). Moreover, proposed model provided encouraging results during high dynamic traffic flow.

Keywords: SDN, IoT, DL, ML, DRS

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19842 A Radioprotective Effect of Nanoceria (CNPs), Magnetic Flower-Like Iron Oxide Microparticles (FIOMPs), and Vitamins C and E on Irradiated BSA Protein

Authors: Hajar Zarei, AliAkbar Zarenejadatashgah, Vuk Uskoković, Hiroshi Watabe

Abstract:

The reactive oxygen species (ROS) generated by radiation in nuclear diagnostic imaging and radiotherapy could damage the structure of the proteins in noncancerous cells surrounding the tumor. The critical factor in many age-related diseases, such as Alzheimer, Parkinson, or Huntington diseases, is the oxidation of proteins by the ROS as molecular triggers of the given pathologies. Our studies by spectroscopic experiments showed doses close to therapeutic ones (1 to 5 Gy) could lead to changes of secondary and tertiary structures in BSA protein macromolecule as a protein model as well as the aggregation of polypeptide chain but without the fragmentation. For this reason, we investigated the radioprotective effects of natural (vitamin C and E) and synthetic materials (CNPs and FIOMPs) on the structural changes in BSA protein induced by gamma irradiation at a therapeutic dose (3Gy). In the presence of both vitamins and synthetic materials, the spectroscopic studies revealed that irradiated BSA was protected from the structural changes caused by ROS, according to in vitro research. The radioprotective property of CNPs and FIOMPs arises from enzyme mimetic activities (catalase, superoxide dismutase, and peroxidase) and their antioxidant capability against hydroxyl radicals. In the case of FIOMPs, a porous structure also leads to increased ROS recombination with each other in the same radiolytic track and subsequently decreased encounters with BSA. The hydrophilicity of vitamin C resulted in the major scavenging of ROS in the solvent, whereas hydrophobic vitamin E localized on the nonpolar patches of the BSA surface, where it did not only neutralize them thanks to the moderate BSA binding constant but also formed a barrier for diffusing ROS. To the best of our knowledge, there has been a persistent lack of studies investigating the radioactive effect of mentioned materials on proteins. Therefore, the results of our studies can open a new widow for application of these common dietary ingredients and new synthetic NPs in improving the safety of radiotherapy.

Keywords: reactive oxygen species, spectroscopy, bovine serum albumin, gamma radiation, radioprotection

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19841 Research Developments in Vibration Control of Structure Using Tuned Liquid Column Dampers: A State-of-the-Art Review

Authors: Jay Gohel, Anant Parghi

Abstract:

A tuned liquid column damper (TLCD) is a modified passive system of tuned mass damper, where a liquid is used in place of mass in the structure. A TLCD consists of U-shaped tube with an orifice that produces damping against the liquid motion in the tube. This paper provides a state-of-the-art review on the vibration control of wind and earthquake excited structures using liquid dampers. Further, the paper will also discuss the theoretical background of TCLD, history of liquid dampers and existing literature on experimental, numerical, and analytical study. The review will also include different configuration of TLCD viz single TLCD, multi tuned liquid column damper (MTLCD), TLCD-Interior (TLCDI), tuned liquid column ball damper (TLCBD), tuned liquid column ball gas damper (TLCBGD), and pendulum liquid column damper (PLCD). The dynamic characteristics of the different configurate TLCD system and their effectiveness in reducing the vibration of structure will be discussed. The effectiveness of semi-active TLCD will be also discussed with reference to experimental and analytical results. In addition, the review will also provide the numerous examples of implemented TLCD to control the vibration in real structures. Based on the comprehensive review of literature, some important conclusions will be made and the need for future research will be identified for vibration control of structures using TLCD.

Keywords: earthquake, wind, tuned liquid column damper, passive response control, structures

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19840 Modeling and Optimization of a Microfluidic Electrochemical Cell for the Electro-Reduction of CO₂ to CH₃OH

Authors: Barzin Rajabloo, Martin Desilets

Abstract:

First, an electrochemical model for the reduction of CO₂ into CH₃OH is developed in which mass and charge transfer, reactions at the surface of the electrodes and fluid flow of the electrolyte are considered. This mathematical model is developed in COMSOL Multiphysics® where both secondary and tertiary current distribution interfaces are coupled to consider concentrations and potentials inside different parts of the cell. Constant reaction rates are assumed as the fitted parameters to minimize the error between experimental data and modeling results. The model is validated through a comparison with experimental data in terms of faradaic efficiency for production of CH₃OH, the current density in different applied cathode potentials as well as current density in different electrolyte flow rates. The comparison between model outputs and experimental measurements shows a good agreement. The model indicates the higher hydrogen evolution in comparison with CH₃OH production as well as mass transfer limitation caused by CO₂ concentration, which are consistent with findings in the literature. After validating the model, in the second part of the study, some design parameters of the cell, such as cathode geometry and catholyte/anolyte channel widths, are modified to reach better performance and higher faradaic efficiency of methanol production.

Keywords: carbon dioxide, electrochemical reduction, methanol, modeling

Procedia PDF Downloads 94
19839 Preparation and CO2 Permeation Properties of Carbonate-Ceramic Dual-Phase Membranes

Authors: H. Ishii, S. Araki, H. Yamamoto

Abstract:

In recent years, the carbon dioxide (CO2) separation technology is required in terms of the reduction of emission of global warming gases and the efficient use of fossil fuels. Since the emission amount of CO2 gas occupies the large part of greenhouse effect gases, it is considered that CO2 have the most influence on global warming. Therefore, we need to establish the CO2 separation technologies with high efficiency at low cost. In this study, we focused on the membrane separation compared with conventional separation technique such as distillation or cryogenic separation. In this study, we prepared carbonate-ceramic dual-phase membranes to separate CO2 at high temperature. As porous ceramic substrate, the (Pr0.9La0.1)2(Ni0.74Cu0.21Ga0.05)O4+σ, La0.6Sr0.4Ti0.3 Fe0.7O3 and Ca0.8Sr0.2Ti0.7Fe0.3O3-α (PLNCG, LSTF and CSTF) were examined. PLNCG, LSTF and CSTF have the perovskite structure. The perovskite structure has high stability and shows ion-conducting doped by another metal ion. PLNCG, LSTF and CSTF have perovskite structure and has high stability and high oxygen ion diffusivity. PLNCG, LSTF and CSTF powders were prepared by a solid-phase process using the appropriate carbonates or oxides. To prepare porous substrates, these powders mixed with carbon black (20 wt%) and a few drops of polyvinyl alcohol (5 wt%) aqueous solution. The powder mixture were packed into stainless steel mold (13 mm) and uniaxially pressed into disk shape under a pressure of 20 MPa for 1 minute. PLNCG, LSTF and CSTF disks were calcined in air for 6 h at 1473, 1573 and 1473 K, respectively. The carbonate mixture (Li2CO3/Na2CO3/K2CO3: 42.5/32.5/25 in mole percent ratio) was placed inside a crucible and heated to 793 K. Porous substrates were infiltrated with the molten carbonate mixture at 793 K. Crystalline structures of the fresh membranes and after the infiltration with the molten carbonate mixtures were determined by X-ray diffraction (XRD) measurement. We confirmed the crystal structure of PLNCG and CSTF slightly changed after infiltration with the molten carbonate mixture. CO2 permeation experiments with PLNCG-carbonate, LSTF-carbonate and CSTF-carbonate membranes were carried out at 773-1173 K. The gas mixture of CO2 (20 mol%) and He was introduced at the flow rate of 50 ml/min to one side of membrane. The permeated CO2 was swept by N2 (50 ml/min). We confirmed the effect of ceramic materials and temperature on the CO2 permeation at high temperature.

Keywords: membrane, perovskite structure, dual-phase, carbonate

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19838 A Fresh Look at Tense System of Qashqaie Dialect of Turkish Language

Authors: Mohammad Sharifi Bohlouli

Abstract:

Turkish language with many dialects is native or official language of great number of people all around the world. The Qashqaie dialect of Turkish language is spoken by the Qashqaie tribe mostly scattered in the southern part of Iran. This paper aims at analyzing the tense system of this dialect to detect the type and number of tense and aspects available to its speakers. To collect a reliable data, a group of 50 old native speakers were randomly chosen as the informants and different techniques such as; Shuy et al interviews, selective listening ,and eavesdropping were used. The results of data analysis showed that the tense system in the Qashqaie dialect of Turkish language includes 3 absolute tenses , 6 aspectual , and 2 subjunctive ones. The interesting part of the study is that Qashqaie dialect enables its speakers to make a kind of aspectual opposition through verb structure which seems to be almost impossible through verb forms in any other nonturkish languages. For example in the following examples sentences 1 &2 and 3&4 have the same translation In English although they are different in both meaning and structure. 1. Ali ensha yazirdi. 2. Ali ensha yazirmush. (Ali was writing a composition.) 3. Ali yadmishdi. 4. Ali yadmishimish. ( Ali had slept.) The changes in the verb structure in Qashqaie dialect enables its speakers to say that whether the doer of the action remembers the process of doing the action or not. So, it presents a new aspectual opposition as Observed /nonobserved. The research findings reveal many other regularities and linguistic features that can be useful for linguists interested in Turkish in general and for those interested in tense and aspect and also they can be helpful for different pedagogical purposes including teaching and translating.

Keywords: qashqaie dialect, tense, aspect, linguistics, Turkish Language

Procedia PDF Downloads 349
19837 A Dynamic Neural Network Model for Accurate Detection of Masked Faces

Authors: Oladapo Tolulope Ibitoye

Abstract:

Neural networks have become prominent and widely engaged in algorithmic-based machine learning networks. They are perfect in solving day-to-day issues to a certain extent. Neural networks are computing systems with several interconnected nodes. One of the numerous areas of application of neural networks is object detection. This is a prominent area due to the coronavirus disease pandemic and the post-pandemic phases. Wearing a face mask in public slows the spread of the virus, according to experts’ submission. This calls for the development of a reliable and effective model for detecting face masks on people's faces during compliance checks. The existing neural network models for facemask detection are characterized by their black-box nature and large dataset requirement. The highlighted challenges have compromised the performance of the existing models. The proposed model utilized Faster R-CNN Model on Inception V3 backbone to reduce system complexity and dataset requirement. The model was trained and validated with very few datasets and evaluation results shows an overall accuracy of 96% regardless of skin tone.

Keywords: convolutional neural network, face detection, face mask, masked faces

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19836 A Comparative Analysis of ARIMA and Threshold Autoregressive Models on Exchange Rate

Authors: Diteboho Xaba, Kolentino Mpeta, Tlotliso Qejoe

Abstract:

This paper assesses the in-sample forecasting of the South African exchange rates comparing a linear ARIMA model and a SETAR model. The study uses a monthly adjusted data of South African exchange rates with 420 observations. Akaike information criterion (AIC) and the Schwarz information criteria (SIC) are used for model selection. Mean absolute error (MAE), root mean squared error (RMSE) and mean absolute percentage error (MAPE) are error metrics used to evaluate forecast capability of the models. The Diebold –Mariano (DM) test is employed in the study to check forecast accuracy in order to distinguish the forecasting performance between the two models (ARIMA and SETAR). The results indicate that both models perform well when modelling and forecasting the exchange rates, but SETAR seemed to outperform ARIMA.

Keywords: ARIMA, error metrices, model selection, SETAR

Procedia PDF Downloads 230