Search results for: dead space model
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 19649

Search results for: dead space model

18749 Convergence Analysis of Reactive Power Based Schemes Used in Sensorless Control of Induction Motors

Authors: N. Ben Si Ali, N. Benalia, N. Zerzouri

Abstract:

Many electronic drivers for the induction motor control are based on sensorless technologies. Speed and torque control is usually attained by application of a speed or position sensor which requires the additional mounting space, reduce the reliability and increase the cost. This paper seeks to analyze dynamical performances and sensitivity to motor parameter changes of reactive power based technique used in sensorless control of induction motors. Validity of theoretical results is verified by simulation.

Keywords: adaptive observers, model reference adaptive system, RP-based estimator, sensorless control, stability analysis

Procedia PDF Downloads 541
18748 Asset Pricing Model: A Quality Paradigm

Authors: Urmi Khatri

Abstract:

Capital asset pricing model (CAPM) draws a direct relationship between the risk and the expected rate of return. There was a criticism on the beta and the assumptions of CAPM, as they are not applicable in the real world. Fama French Three Factor Model and Fama French Five Factor Model have given different factors, which have an impact on the return of any asset like size, value, investment and profitability. This study proposes to see Capital Asset pricing Model through the lenses of the quality aspect. In the study, the six factors are studied. The Fama French Five Factor Model and addition of the quality dimension are studied. Here, Graham’s seven quality and quantity criteria are measured to determine the score of the sample firms. Thus, this study tries to check the model fit. The beta coefficient of the quality dimension and the R square value is seen to determine validity of the proposed model. The sample is drawn from the firms listed on Indian Stock Exchange (BSE). For the study, only nonfinancial firms are been selected. The time period of the study is from January 1999 to December 2019. Hence, the primary objective of the study is to check how robust the model becomes after giving the quality dimension to the capital asset pricing model in addition to the size, value, profitability and investment.

Keywords: asset pricing model, CAPM, Graham’s score, G-score, multifactor model, quality

Procedia PDF Downloads 151
18747 Advancing in Cricket Analytics: Novel Approaches for Pitch and Ball Detection Employing OpenCV and YOLOV8

Authors: Pratham Madnur, Prathamkumar Shetty, Sneha Varur, Gouri Parashetti

Abstract:

In order to overcome conventional obstacles, this research paper investigates novel approaches for cricket pitch and ball detection that make use of cutting-edge technologies. The research integrates OpenCV for pitch inspection and modifies the YOLOv8 model for cricket ball detection in order to overcome the shortcomings of manual pitch assessment and traditional ball detection techniques. To ensure flexibility in a range of pitch environments, the pitch detection method leverages OpenCV’s color space transformation, contour extraction, and accurate color range defining features. Regarding ball detection, the YOLOv8 model emphasizes the preservation of minor object details to improve accuracy and is specifically trained to the unique properties of cricket balls. The methods are more reliable because of the careful preparation of the datasets, which include novel ball and pitch information. These cutting-edge methods not only improve cricket analytics but also set the stage for flexible methods in more general sports technology applications.

Keywords: OpenCV, YOLOv8, cricket, custom dataset, computer vision, sports

Procedia PDF Downloads 63
18746 T-S Fuzzy Modeling Based on Power Coefficient Limit Nonlinearity Applied to an Isolated Single Machine Load Frequency Deviation Control

Authors: R. S. Sheu, H. Usman, M. S. Lawal

Abstract:

Takagi-Sugeno (T-S) fuzzy model based control of a load frequency deviation in a single machine with limit nonlinearity on power coefficient is presented in the paper. Two T-S fuzzy rules with only rotor angle variable as input in the premise part, and linear state space models in the consequent part involving characteristic matrices determined from limits set on the power coefficient constant are formulated, state feedback control gains for closed loop control was determined from the formulated Linear Matrix Inequality (LMI) with eigenvalue optimization scheme for asymptotic and exponential stability (speed of esponse). Numerical evaluation of the closed loop object was carried out in Matlab. Simulation results generated of both the open and closed loop system showed the effectiveness of the control scheme in maintaining load frequency stability.

Keywords: T-S fuzzy model, state feedback control, linear matrix inequality (LMI), frequency deviation control

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18745 Performance of the Cmip5 Models in Simulation of the Present and Future Precipitation over the Lake Victoria Basin

Authors: M. A. Wanzala, L. A. Ogallo, F. J. Opijah, J. N. Mutemi

Abstract:

The usefulness and limitations in climate information are due to uncertainty inherent in the climate system. For any given region to have sustainable development it is important to apply climate information into its socio-economic strategic plans. The overall objective of the study was to assess the performance of the Coupled Model Inter-comparison Project (CMIP5) over the Lake Victoria Basin. The datasets used included the observed point station data, gridded rainfall data from Climate Research Unit (CRU) and hindcast data from eight CMIP5. The methodology included trend analysis, spatial analysis, correlation analysis, Principal Component Analysis (PCA) regression analysis, and categorical statistical skill score. Analysis of the trends in the observed rainfall records indicated an increase in rainfall variability both in space and time for all the seasons. The spatial patterns of the individual models output from the models of MPI, MIROC, EC-EARTH and CNRM were closest to the observed rainfall patterns.

Keywords: categorical statistics, coupled model inter-comparison project, principal component analysis, statistical downscaling

Procedia PDF Downloads 363
18744 Complex Rigid-Plastic Deformation Model of Tow Degree of Freedom Mechanical System under Impulsive Force

Authors: Abdelouaheb Rouabhi

Abstract:

In order to study the plastic resource of structures, the elastic-plastic single degree of freedom model described by Prandtl diagram is widely used. The generalization of this model to tow degree of freedom beyond the scope of a simple rigid-plastic system allows investigating the plastic resource of structures under complex disproportionate by individual components of deformation (earthquake). This macro-model greatly increases the accuracy of the calculations carried out. At the same time, the implementation of the proposed macro-model calculations easier than the detailed dynamic elastic-plastic calculations existing software systems such as ANSYS.

Keywords: elastic-plastic, single degree of freedom model, rigid-plastic system, plastic resource, complex plastic deformation, macro-model

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18743 Brainwave Classification for Brain Balancing Index (BBI) via 3D EEG Model Using k-NN Technique

Authors: N. Fuad, M. N. Taib, R. Jailani, M. E. Marwan

Abstract:

In this paper, the comparison between k-Nearest Neighbor (kNN) algorithms for classifying the 3D EEG model in brain balancing is presented. The EEG signal recording was conducted on 51 healthy subjects. Development of 3D EEG models involves pre-processing of raw EEG signals and construction of spectrogram images. Then, maximum PSD values were extracted as features from the model. There are three indexes for the balanced brain; index 3, index 4 and index 5. There are significant different of the EEG signals due to the brain balancing index (BBI). Alpha-α (8–13 Hz) and beta-β (13–30 Hz) were used as input signals for the classification model. The k-NN classification result is 88.46% accuracy. These results proved that k-NN can be used in order to predict the brain balancing application.

Keywords: power spectral density, 3D EEG model, brain balancing, kNN

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18742 Federal College of Education Kano

Authors: Mahnaz Babaei Morad, Mojtaba Zargarzadeh, Behnaz Babaei Morad, Najmeh Salari Nasab

Abstract:

Green roofs and walls are one of the key elements of sustainable design in ecology design of cities. Lack of open space and urban green at different scales from one neighborhood to district is as subject that has become challenge for urban management Use change from green space to other use is familiar for Iranian citizens. The high price of land in this area, it seems only justified reason for municipalities that reduce the green space per capita. In this paper, examines the rooftops of Iranian city as a fifth facade, as well as the opportunity to offset some of the capital's urban spaces that has been removed. Today green roof isn't a matter of taste in the world. Be proportional to the quantity and quality of the architecture become the first concern of urban professionals and ecological approaches such as "sustainable" and "green architecture" is checked. In this paper we review and present examples of green roofs have been executed in Iran over the past decade. Survey some of the urban management policies in leading province in this article constitutes the second dimension. The purpose of this paper is study example of green roof performance in different parts of Iran, along with criteria for sustainable urban development and achieves the policies and components collection of implementation sustainable development , specific of Iranian green roof and monitor the develops ways to it.

Keywords: sustainable development, green roofs, Iran, green architecture

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18741 Good Governance: An Effective Public Participation Approach for Urban Development of City Centers

Authors: Lojaine Okacha

Abstract:

In the past half-century, researchers started paying attention to enhancing the performance of urban spaces. Their idea of performance comprised urban climate performance, space synthesis, economic performance, and enhancing the quality of life in space. However, they all agreed that the key to achieving any of the previously mentioned development projects is good governance. Having good governance allows citizens to participate freely in the urbanization or development projects within cities. Consequently, using the city resources and assets as efficiently as possible, and ensures the fulfillment of the users’ needs and requests. This paper aims to propose an effective participation framework to help citizens have their voices heard and participate in the decisions that will affect their living situation. The framework allows governments to use their public resources to their best. However, this study focuses on public participation in third-world countries with unitary decentralized governance systems such as Egypt. It summarizes the challenges facing the participation practices, identifies the keys to a successful participation process, and draws on dominant effective participation practice lying on the relationship between the levels of participation, stakeholders participating, the urban development stages, the city-systems, and participation process. These components are integrated to create a real-world effective participation Framework. The results of the analysis were incredible and produced a functional and progressive approach for effective public participation to introduce to the governments. The model itself is combined with additional principles allowing the best practice to the process. The framework is finally compared with a real case of urban development.

Keywords: public participation, good governance, urban development, city systems

Procedia PDF Downloads 190
18740 Ontology for a Voice Transcription of OpenStreetMap Data: The Case of Space Apprehension by Visually Impaired Persons

Authors: Said Boularouk, Didier Josselin, Eitan Altman

Abstract:

In this paper, we present a vocal ontology of OpenStreetMap data for the apprehension of space by visually impaired people. Indeed, the platform based on produsage gives a freedom to data producers to choose the descriptors of geocoded locations. Unfortunately, this freedom, called also folksonomy leads to complicate subsequent searches of data. We try to solve this issue in a simple but usable method to extract data from OSM databases in order to send them to visually impaired people using Text To Speech technology. We focus on how to help people suffering from visual disability to plan their itinerary, to comprehend a map by querying computer and getting information about surrounding environment in a mono-modal human-computer dialogue.

Keywords: TTS, ontology, open street map, visually impaired

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18739 Identification of Dynamic Friction Model for High-Precision Motion Control

Authors: Martin Goubej, Tomas Popule, Alois Krejci

Abstract:

This paper deals with experimental identification of mechanical systems with nonlinear friction characteristics. Dynamic LuGre friction model is adopted and a systematic approach to parameter identification of both linear and nonlinear subsystems is given. The identification procedure consists of three subsequent experiments which deal with the individual parts of plant dynamics. The proposed method is experimentally verified on an industrial-grade robotic manipulator. Model fidelity is compared with the results achieved with a static friction model.

Keywords: mechanical friction, LuGre model, friction identification, motion control

Procedia PDF Downloads 407
18738 Genesis of Entrepreneur Business Models in New Ventures

Authors: Arash Najmaei, Jo Rhodes, Peter Lok, Zahra Sadeghinejad

Abstract:

In this article, we endeavor to explore how a new business model comes into existence in the Australian cloud-computing eco-system. Findings from multiple case study methodology reveal that to develop a business model new ventures adopt a three-phase approach. In the first phase, labelled as business model ideation (BMID) various ideas for a viable business model are generated from both internal and external networks of the entrepreneurial team and the most viable one is chosen. Strategic consensus and commitment are generated in the second phase. This phase is a business modelling strategic action phase. We labelled this phase as business model strategic commitment (BMSC) because through commitment and the subsequent actions of executives resources are pooled, coordinated and allocated to the business model. Three complementary sets of resources shape the business model: managerial (MnRs), marketing (MRs) and technological resources (TRs). The third phase is the market-test phase where the business model is reified through the delivery of the intended value to customers and conversion of revenue into profit. We labelled this phase business model actualization (BMAC). Theoretical and managerial implications of these findings will be discussed and several directions for future research will be illuminated.

Keywords: entrepreneur business model, high-tech venture, resources, conversion of revenue

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18737 Assessing Moisture Adequacy over Semi-arid and Arid Indian Agricultural Farms using High-Resolution Thermography

Authors: Devansh Desai, Rahul Nigam

Abstract:

Crop water stress (W) at a given growth stage starts to set in as moisture availability (M) to roots falls below 75% of maximum. It has been found that ratio of crop evapotranspiration (ET) and reference evapotranspiration (ET0) is an indicator of moisture adequacy and is strongly correlated with ‘M’ and ‘W’. The spatial variability of ET0 is generally less over an agricultural farm of 1-5 ha than ET, which depends on both surface and atmospheric conditions, while the former depends only on atmospheric conditions. Solutions from surface energy balance (SEB) and thermal infrared (TIR) remote sensing are now known to estimate latent heat flux of ET. In the present study, ET and moisture adequacy index (MAI) (=ET/ET0) have been estimated over two contrasting western India agricultural farms having rice-wheat system in semi-arid climate and arid grassland system, limited by moisture availability. High-resolution multi-band TIR sensing observations at 65m from ECOSTRESS (ECOsystemSpaceborne Thermal Radiometer Experiment on Space Station) instrument on-board International Space Station (ISS) were used in an analytical SEB model, STIC (Surface Temperature Initiated Closure) to estimate ET and MAI. The ancillary variables used in the ET modeling and MAI estimation were land surface albedo, NDVI from close-by LANDSAT data at 30m spatial resolution, ET0 product at 4km spatial resolution from INSAT 3D, meteorological forcing variables from short-range weather forecast on air temperature and relative humidity from NWP model. Farm-scale ET estimates at 65m spatial resolution were found to show low RMSE of 16.6% to 17.5% with R2 >0.8 from 18 datasets as compared to reported errors (25 – 30%) from coarser-scale ET at 1 to 8 km spatial resolution when compared to in situ measurements from eddy covariance systems. The MAI was found to show lower (<0.25) and higher (>0.5) magnitudes in the contrasting agricultural farms. The study showed the potential need of high-resolution high-repeat spaceborne multi-band TIR payloads alongwith optical payload in estimating farm-scale ET and MAI for estimating consumptive water use and water stress. A set of future high-resolution multi-band TIR sensors are planned on-board Indo-French TRISHNA, ESA’s LSTM, NASA’s SBG space-borne missions to address sustainable irrigation water management at farm-scale to improve crop water productivity. These will provide precise and fundamental variables of surface energy balance such as LST (Land Surface Temperature), surface emissivity, albedo and NDVI. A synchronization among these missions is needed in terms of observations, algorithms, product definitions, calibration-validation experiments and downstream applications to maximize the potential benefits.

Keywords: thermal remote sensing, land surface temperature, crop water stress, evapotranspiration

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18736 Model of Multi-Criteria Evaluation for Railway Lines

Authors: Juraj Camaj, Martin Kendra, Jaroslav Masek

Abstract:

The paper is focused to the evaluation railway tracks in the Slovakia by using Multi-Criteria method. Evaluation of railway tracks has important impacts for the assessment of investment in technical equipment. Evaluation of railway tracks also has an important impact for the allocation of marshalling yards. Marshalling yards are in transport model as centers for the operation assigned catchment area. This model is one of the effective ways to meet the development strategy of the European Community's railways. By applying this model in practice, a transport company can guarantee a higher quality of service and then expect an increase in performance. The model is also applicable to other rail networks. This model supplements a theoretical problem of train formation problem of new ways of looking at evaluation of factors affecting the organization of wagon flows.

Keywords: railway track, multi-criteria methods, evaluation, transportation model

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18735 Anti-Gravity to Neo-Concretism: The Epodic Spaces of Non-Objective Art

Authors: Alexandra Kennedy

Abstract:

Making use of the notion of ‘epodic spaces’ this paper presents a reconsideration of non-objective art practices, proposing alternatives to established materialist, formalist, process-based conceptualist approaches to such work. In his Neo-Concrete Manifesto (1959) Ferreira Gullar (1930-2016) sought to create a distinction between various forms of non-objective art. He distinguished the ‘geometric’ arts of neoplasticism, constructivism, and suprematism – which he described as ‘dangerously acute rationalism’ – from other non-objective practices. These alternatives, he proposed, have an expressive potential lacking in the former and this formed the basis for their categorisation as neo-concrete. Gullar prioritized the phenomenological over the rational, with an emphasis on the role of the spectator (a key concept of minimalism). Gullar highlighted the central role of sensual experience, colour and the poetic in such work. In the early twentieth century, Russian Cosmism – an esoteric philosophical movement – was highly influential on Russian avant-garde artists and can account for suprematist artists’ interest in, and approach to, planar geometry and four-dimensional space as demonstrated in the abstract paintings of Kasimir Malevich (1879-1935). Nikolai Fyodorov (1823-1903) promoted the idea of anti-gravity and cosmic space as the field for artistic activity. The artist and writer Kuzma Petrov-Vodkin (1878-1939) wrote on the concept of Euclidean space, the overcoming of such rational conceptions of space and the breaking free from the gravitational field and the earth’s sphere. These imaginary spaces, which also invoke a bodily experience, present a poetic dimension to the work of the suprematists. It is a dimension that arguably aligns more with Gullar’s formulation of his neo-concrete rather than that of his alignment of Suprematism with rationalism. While found in experiments with planar geometry, the interest in forms suggestive of an experience of breaking free–both physically from the earth and conceptually from rational, mathematical space (in a pre-occupation with non-Euclidean space and anti-geometry) and in their engagement with the spatial properties of colour, Suprematism presents itself as imaginatively epodic. The paper discusses both historical and contemporary non-objective practices in this context, drawing attention to the manner in which the category of the non-objective is used to categorise art works which are, arguably, qualitatively different.

Keywords: anti-gravity, neo-concrete, non-Euclidian geometry, non-objective painting

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18734 Research on Coordination Strategies for Coordinating Supply Chain Based on Auction Mechanisms

Authors: Changtong Wang, Lingyun Wei

Abstract:

The combination of auctions and supply chains is of great significance in improving the supply chain management system and enhancing the efficiency of economic and social operations. To address the gap in research on supply chain strategies under the auction mechanism, a model is developed for the 1-N auction model in a complete information environment, and it is concluded that the two-part contract auction model for retailers in this model can achieve supply chain coordination. The model is validated by substituting the model into the scenario of a fresh-cut flower industry flower auction in exchange for arithmetic examples to further prove the validity of the conclusions.

Keywords: auction mechanism, supply chain coordination strategy, fresh cut flowers industry, supply chain management

Procedia PDF Downloads 118
18733 Adaptive Thermal Comfort Model for Air-Conditioned Lecture Halls in Malaysia

Authors: B. T. Chew, S. N. Kazi, A. Amiri

Abstract:

This paper presents an adaptive thermal comfort model study in the tropical country of Malaysia. A number of researchers have been interested in applying the adaptive thermal comfort model to different climates throughout the world, but so far no study has been performed in Malaysia. For the use as a thermal comfort model, which better applies to hot and humid climates, the adaptive thermal comfort model was developed as part of this research by using the collected results from a large field study in six lecture halls with 178 students. The relationship between the operative temperature and behavioral adaptations was determined. In the developed adaptive model, the acceptable indoor neutral temperatures lay within the range of 23.9-26.0 oC, with outdoor temperatures ranging between 27.0–34.6oC. The most comfortable temperature for students in the lecture hall was 25.7 oC.

Keywords: hot and humid, lecture halls, neutral temperature, adaptive thermal comfort model

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18732 Proton Irradiation Testing on Commercial Enhancement Mode GaN Power Transistor

Authors: L. Boyaci

Abstract:

Two basic equipment of electrical power subsystem of space satellites are Power Conditioning Unit (PCU) and Power Distribution Unit (PDU). Today, the main switching element used in power equipment in satellites is silicon (Si) based radiation-hardened MOSFET. GaNFETs have superior performances over MOSFETs in terms of their conduction and switching characteristics. GaNFET has started to take MOSFET’s place in many applications in industry especially by virtue of its switching performances. If GaNFET can also be used in equipment for space applications, this would be great revolution for future space power subsystem designs. In this study, the effect of proton irradiation on Gallium Nitride based power transistors was investigated. Four commercial enhancement mode GaN power transistors from Efficient Power Conversion Corporation (EPC) are irradiated with 30MeV protons while devices are switching. Flux of 8.2x10⁹ protons/cm²/s is applied for 12.5 seconds to reach ultimate fluence of 10¹¹ protons/cm². Vgs-Ids characteristics are measured and recorded for each device before, during and after irradiation. It was observed that if there would be destructive events. Proton induced permanent damage on devices is not observed. All the devices remained healthy and continued to operate. For two of these devices, further irradiation is applied with same flux for 30 minutes up to a total fluence level of 1.476x10¹³ protons/cm². We observed that GaNFETs are fully functional under this high level of radiation and no destructive events and irreversible failures took place for transistors. Results reveal that irradiated GaNFET in this experiment has radiation tolerance under proton testing and very important candidate for being one of the future power switching element in space.

Keywords: enhancement mode GaN power transistors, proton irradiation effects, radiation tolerance

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18731 Method of Parameter Calibration for Error Term in Stochastic User Equilibrium Traffic Assignment Model

Authors: Xiang Zhang, David Rey, S. Travis Waller

Abstract:

Stochastic User Equilibrium (SUE) model is a widely used traffic assignment model in transportation planning, which is regarded more advanced than Deterministic User Equilibrium (DUE) model. However, a problem exists that the performance of the SUE model depends on its error term parameter. The objective of this paper is to propose a systematic method of determining the appropriate error term parameter value for the SUE model. First, the significance of the parameter is explored through a numerical example. Second, the parameter calibration method is developed based on the Logit-based route choice model. The calibration process is realized through multiple nonlinear regression, using sequential quadratic programming combined with least square method. Finally, case analysis is conducted to demonstrate the application of the calibration process and validate the better performance of the SUE model calibrated by the proposed method compared to the SUE models under other parameter values and the DUE model.

Keywords: parameter calibration, sequential quadratic programming, stochastic user equilibrium, traffic assignment, transportation planning

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18730 Model-Based Control for Piezoelectric-Actuated Systems Using Inverse Prandtl-Ishlinskii Model and Particle Swarm Optimization

Authors: Jin-Wei Liang, Hung-Yi Chen, Lung Lin

Abstract:

In this paper feedforward controller is designed to eliminate nonlinear hysteresis behaviors of a piezoelectric stack actuator (PSA) driven system. The control design is based on inverse Prandtl-Ishlinskii (P-I) hysteresis model identified using particle swarm optimization (PSO) technique. Based on the identified P-I model, both the inverse P-I hysteresis model and feedforward controller can be determined. Experimental results obtained using the inverse P-I feedforward control are compared with their counterparts using hysteresis estimates obtained from the identified Bouc-Wen model. Effectiveness of the proposed feedforward control scheme is demonstrated. To improve control performance feedback compensation using traditional PID scheme is adopted to integrate with the feedforward controller.

Keywords: the Bouc-Wen hysteresis model, particle swarm optimization, Prandtl-Ishlinskii model, automation engineering

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18729 Influence of Local Soil Conditions on Optimal Load Factors for Seismic Design of Buildings

Authors: Miguel A. Orellana, Sonia E. Ruiz, Juan Bojórquez

Abstract:

Optimal load factors (dead, live and seismic) used for the design of buildings may be different, depending of the seismic ground motion characteristics to which they are subjected, which are closely related to the type of soil conditions where the structures are located. The influence of the type of soil on those load factors, is analyzed in the present study. A methodology that is useful for establishing optimal load factors that minimize the cost over the life cycle of the structure is employed; and as a restriction, it is established that the probability of structural failure must be less than or equal to a prescribed value. The life-cycle cost model used here includes different types of costs. The optimization methodology is applied to two groups of reinforced concrete buildings. One set (consisting on 4-, 7-, and 10-story buildings) is located on firm ground (with a dominant period Ts=0.5 s) and the other (consisting on 6-, 12-, and 16-story buildings) on soft soil (Ts=1.5 s) of Mexico City. Each group of buildings is designed using different combinations of load factors. The statistics of the maximums inter-story drifts (associated with the structural capacity) are found by means of incremental dynamic analyses. The buildings located on firm zone are analyzed under the action of 10 strong seismic records, and those on soft zone, under 13 strong ground motions. All the motions correspond to seismic subduction events with magnitudes M=6.9. Then, the structural damage and the expected total costs, corresponding to each group of buildings, are estimated. It is concluded that the optimal load factors combination is different for the design of buildings located on firm ground than that for buildings located on soft soil.

Keywords: life-cycle cost, optimal load factors, reinforced concrete buildings, total costs, type of soil

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18728 Yang-Lee Edge Singularity of the Infinite-Range Ising Model

Authors: Seung-Yeon Kim

Abstract:

The Ising model, consisting magnetic spins, is the simplest system showing phase transitions and critical phenomena at finite temperatures. The Ising model has played a central role in our understanding of phase transitions and critical phenomena. Also, the Ising model explains the gas-liquid phase transitions accurately. However, the Ising model in a nonzero magnetic field has been one of the most intriguing and outstanding unsolved problems. We study analytically the partition function zeros in the complex magnetic-field plane and the Yang-Lee edge singularity of the infinite-range Ising model in an external magnetic field. In addition, we compare the Yang-Lee edge singularity of the infinite-range Ising model with that of the square-lattice Ising model in an external magnetic field.

Keywords: Ising ferromagnet, magnetic field, partition function zeros, Yang-Lee edge singularity

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18727 Study on Accurate Calculation Method of Model Attidude on Wind Tunnel Test

Authors: Jinjun Jiang, Lianzhong Chen, Rui Xu

Abstract:

The accurate of model attitude angel plays an important role on the aerodynamic test results in the wind tunnel test. The original method applies the spherical coordinate system transformation to obtain attitude angel calculation.The model attitude angel is obtained by coordinate transformation and spherical surface mapping applying the nominal attitude angel (the balance attitude angel in the wind tunnel coordinate system) indicated by the mechanism. First, the coordinate transformation of this method is not only complex but also difficult to establish the transformed relationship between the space coordinate systems especially after many steps of coordinate transformation, moreover it cannot realize the iterative calculation of the interference relationship between attitude angels; Second, during the calculate process to solve the problem the arc is approximately used to replace the straight line, the angel for the tangent value, and the inverse trigonometric function is applied. Therefore, in the calculation of attitude angel, the process is complex and inaccurate, which can be solved approximately when calculating small attack angel. However, with the advancing development of modern aerodynamic unsteady research, the aircraft tends to develop high or super large attack angel and unsteadyresearch field.According to engineering practice and vector theory, the concept of vector angel coordinate systemis proposed for the first time, and the vector angel coordinate system of attitude angel is established.With the iterative correction calculation and avoiding the problem of approximate and inverse trigonometric function solution, the model attitude calculation process is carried out in detail, which validates that the calculation accuracy and accuracy of model attitude angels are improved.Based on engineering and theoretical methods, a vector angel coordinate systemis established for the first time, which gives the transformation and angel definition relations between different flight attitude coordinate systems, that can accurately calculate the attitude angel of the corresponding coordinate systemand determine its direction, especially in the channel coupling calculation, the calculation of the attitude angel between the coordinate systems is only related to the angel, and has nothing to do with the change order s of the coordinate system, whichsimplifies the calculation process.

Keywords: attitude angel, angel vector coordinate system, iterative calculation, spherical coordinate system, wind tunnel test

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18726 Nondecoupling Signatures of Supersymmetry and an Lμ-Lτ Gauge Boson at Belle-II

Authors: Heerak Banerjee, Sourov Roy

Abstract:

Supersymmetry, one of the most celebrated fields of study for explaining experimental observations where the standard model (SM) falls short, is reeling from the lack of experimental vindication. At the same time, the idea of additional gauge symmetry, in particular, the gauged Lμ-Lτ symmetric models have also generated significant interest. They have been extensively proposed in order to explain the tantalizing discrepancy in the predicted and measured value of the muon anomalous magnetic moment alongside several other issues plaguing the SM. While very little parameter space within these models remain unconstrained, this work finds that the γ + Missing Energy (ME) signal at the Belle-II detector will be a smoking gun for supersymmetry (SUSY) in the presence of a gauged U(1)Lμ-Lτ symmetry. A remarkable consequence of breaking the enhanced symmetry appearing in the limit of degenerate (s)leptons is the nondecoupling of the radiative contribution of heavy charged sleptons to the γ-Z΄ kinetic mixing. The signal process, e⁺e⁻ →γZ΄→γ+ME, is an outcome of this ubiquitous feature. Taking the severe constraints on gauged Lμ-Lτ models by several low energy observables into account, it is shown that any significant excess in all but the highest photon energy bin would be an undeniable signature of such heavy scalar fields in SUSY coupling to the additional gauge boson Z΄. The number of signal events depends crucially on the logarithm of the ratio of stau to smuon mass in the presence of SUSY. In addition, the number is also inversely proportional to the e⁺e⁻ collision energy, making a low-energy, high-luminosity collider like Belle-II an ideal testing ground for this channel. This process can probe large swathes of the hitherto free slepton mass ratio vs. additional gauge coupling (gₓ) parameter space. More importantly, it can explore the narrow slice of Z΄ mass (MZ΄) vs. gₓ parameter space still allowed in gauged U(1)Lμ-Lτ models for superheavy sparticles. The spectacular finding that the signal significance is independent of individual slepton masses is an exciting prospect indeed. Further, the prospect that signatures of even superheavy SUSY particles that may have escaped detection at the LHC may show up at the Belle-II detector is an invigorating revelation.

Keywords: additional gauge symmetry, electron-positron collider, kinetic mixing, nondecoupling radiative effect, supersymmetry

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18725 Numerical Modeling of Various Support Systems to Stabilize Deep Excavations

Authors: M. Abdallah

Abstract:

Urban development requires deep excavations near buildings and other structures. Deep excavation has become more a necessity for better utilization of space as the population of the world has dramatically increased. In Lebanon, some urban areas are very crowded and lack spaces for new buildings and underground projects, which makes the usage of underground space indispensable. In this paper, a numerical modeling is performed using the finite element method to study the deep excavation-diaphragm wall soil-structure interaction in the case of nonlinear soil behavior. The study is focused on a comparison of the results obtained using different support systems. Furthermore, a parametric study is performed according to the remoteness of the structure.

Keywords: deep excavation, ground anchors, interaction soil-structure, struts

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18724 Biocompatible Porous Titanium Scaffolds Produced Using a Novel Space Holder Technique

Authors: Yunhui Chen, Damon Kent, Matthew Dargusch

Abstract:

Synthetic scaffolds are a highly promising new approach to replace both autografts and allografts to repair and remodel damaged bone tissue. Biocompatible porous titanium scaffold was manufactured through a powder metallurgy approach. Magnesium powder was used as space holder material which was compacted with titanium powder and removed during sintering. Evaluation of the porosity and mechanical properties showed a high level of compatibility with human bone. Interconnectivity between pores is higher than 95% for porosity as low as 30%. The elastic moduli are 39 GPa, 16 GPa and 9 GPa for 30%, 40% and 50% porosity samples which match well to that of natural bone (4-30 GPa). The yield strengths for 30% and 40% porosity samples of 315 MPa and 175 MPa are superior to that of human bone (130-180 MPa). In-vitro cell culture tests on the scaffold samples using Human Mesenchymal Stem Cells (hMSCs) demonstrated their biocompatibility and indicated osseointegration potential. The scaffolds allowed cells to adhere and spread both on the surface and inside the pore structures. With increasing levels of porosity/interconnectivity, improved cell proliferation is obtained within the pores. It is concluded that samples with 30% porosity exhibit the best biocompatibility. The results suggest that porous titanium scaffolds generated using this manufacturing route have excellent potential for hard tissue engineering applications.

Keywords: scaffolds, MG-63 cell culture, titanium, space holder

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18723 Selective Attention as a Search for the Deceased during the Mourning Process

Authors: Sonia Sirtoli Färber

Abstract:

Objective: This study aims to investigate selective attention in the process of mourning, as a normal reaction to loss. Method: In order to develop this research, we used a systematic bibliographic review, following the process of investigation, cataloging, careful evaluation and synthesis of the documentation, associated with the method of thanatological hemenutics proposed by Elisabeth Kübler-Ross. Conclusion: After a significant loss, especially the death of a loved one or family member, it is normal for the mourner, motivated by absence, to have a false perception of the presence of the deceased. This phenomenon happens whenever the mourner is in the middle of the crowd, because his selective attention causes him to perceive physical characteristics, tone of voice, or feel fragrance of the perfume that the deceased possessed. Details characterizing the dead are perceived by the mourner because he seeks the presence in the absence.

Keywords: Elisabeth Kübler-Ross, mourning, selective attention, thanatology

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18722 Validation of a Fluid-Structure Interaction Model of an Aortic Dissection versus a Bench Top Model

Authors: K. Khanafer

Abstract:

The aim of this investigation was to validate the fluid-structure interaction (FSI) model of type B aortic dissection with our experimental results from a bench-top-model. Another objective was to study the relationship between the size of a septectomy that increases the outflow of the false lumen and its effect on the values of the differential of pressure between true lumen and false lumen. FSI analysis based on Galerkin’s formulation was used in this investigation to study flow pattern and hemodynamics within a flexible type B aortic dissection model using boundary conditions from our experimental data. The numerical results of our model were verified against the experimental data for various tear size and location. Thus, CFD tools have a potential role in evaluating different scenarios and aortic dissection configurations.

Keywords: aortic dissection, fluid-structure interaction, in vitro model, numerical

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18721 Stochastic Optimization of a Vendor-Managed Inventory Problem in a Two-Echelon Supply Chain

Authors: Bita Payami-Shabestari, Dariush Eslami

Abstract:

The purpose of this paper is to develop a multi-product economic production quantity model under vendor management inventory policy and restrictions including limited warehouse space, budget, and number of orders, average shortage time and maximum permissible shortage. Since the “costs” cannot be predicted with certainty, it is assumed that data behave under uncertain environment. The problem is first formulated into the framework of a bi-objective of multi-product economic production quantity model. Then, the problem is solved with three multi-objective decision-making (MODM) methods. Then following this, three methods had been compared on information on the optimal value of the two objective functions and the central processing unit (CPU) time with the statistical analysis method and the multi-attribute decision-making (MADM). The results are compared with statistical analysis method and the MADM. The results of the study demonstrate that augmented-constraint in terms of optimal value of the two objective functions and the CPU time perform better than global criteria, and goal programming. Sensitivity analysis is done to illustrate the effect of parameter variations on the optimal solution. The contribution of this research is the use of random costs data in developing a multi-product economic production quantity model under vendor management inventory policy with several constraints.

Keywords: economic production quantity, random cost, supply chain management, vendor-managed inventory

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18720 Temperature Control and Comfort Level of Elementary School Building with Green Roof in New Taipei City, Taiwan

Authors: Ying-Ming Su, Mei-Shu Huang

Abstract:

To mitigate the urban heat island effect has become a global issue facing the challenge of climate change. Through literature reviews, plant photosynthesis can reduce the carbon dioxide and mitigate the urban heat island effect relatively. Because there are not enough open space and park, green roof has become an important policy in Taiwan. We selected elementary school buildings in northern New Taipei City as research subjects since elementary school is asked priority to build green roof and important educational place to promote green roof concept. Testo 175-H1 recording device was used to record the temperature and humidity difference between roof surface and interior space below roof with and without green roof for the long-term. We also use questionnaire to investigate the awareness of comfort level of green roof and sensation of teachers and students of the elementary school. The results indicated the temperature of roof without greening was higher than that with greening about 2°C. But sometimes during noontime, the temperature of green roof was higher than that of non-green roof related to the character of the accumulation and dissipation of heat of greening probably. The temperature of interior space below green roof was normally lower than that without green roof about 1°C showed that green roof could lower the temperature. The humidity of the green roof was higher than the one without greening also indicated that green roof retained water better. Teachers liked to combine green roof concept in the curriculum, students wished all classes can take turns to maintain the green roof. Teachers and students that school had integrated green roof concept in the curriculum were more willing to participate in the maintenance work of green roof. Teachers and students who may access and touch the green roof can be more aware of the green roof benefit. We suggest architect to increase the accessibility and visibility of green roof, such as a part of the activity space. This idea can be a reference of the green roof curriculum design.

Keywords: comfort level, elementary school, green roof, heat island effect

Procedia PDF Downloads 411