Search results for: cost-based structural optimization
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 7144

Search results for: cost-based structural optimization

2854 Intelligent Decision Support for Wind Park Operation: Machine-Learning Based Detection and Diagnosis of Anomalous Operating States

Authors: Angela Meyer

Abstract:

The operation and maintenance cost for wind parks make up a major fraction of the park’s overall lifetime cost. To minimize the cost and risk involved, an optimal operation and maintenance strategy requires continuous monitoring and analysis. In order to facilitate this, we present a decision support system that automatically scans the stream of telemetry sensor data generated from the turbines. By learning decision boundaries and normal reference operating states using machine learning algorithms, the decision support system can detect anomalous operating behavior in individual wind turbines and diagnose the involved turbine sub-systems. Operating personal can be alerted if a normal operating state boundary is exceeded. The presented decision support system and method are applicable for any turbine type and manufacturer providing telemetry data of the turbine operating state. We demonstrate the successful detection and diagnosis of anomalous operating states in a case study at a German onshore wind park comprised of Vestas V112 turbines.

Keywords: anomaly detection, decision support, machine learning, monitoring, performance optimization, wind turbines

Procedia PDF Downloads 155
2853 Human Resources and Business Result: An Empirical Approach Based on RBV Theory

Authors: Xhevrie Mamaqi

Abstract:

Organization capacity learning is a process referring to the sum total of individual and collective learning through training programs, experience and experimentation, among others. Today, in-business ongoing training is one of the most important strategies for human capital development and it is crucial to sustain and improve workers’ knowledge and skills. Many organizations, firms and business are adopting a strategy of continuous learning, encouraging employees to learn new skills continually to be innovative and to try new processes and work in order to achieve a competitive advantage and superior business results. This paper uses the Resource Based View and Capacities (RBV) approach to construct a hypothetical relationships model between training and business results. The test of the model is applied on transversal data. A sample of 266 business of Spanish sector service has been selected. A Structural Equation Model (SEM) is used to estimate the relationship between ongoing training, represented by two latent dimension denominated Human and Social Capital resources and economic business results. The coefficients estimated have shown the efficient of some training aspects explaining the variation in business results.

Keywords: business results, human and social capital resources, training, RBV theory, SEM

Procedia PDF Downloads 286
2852 The Relationships between the Feelings of Bullying, Self- Esteem, Employee Silence, Anger, Self- Blame and Shame

Authors: Şebnem Aslan, Demet Akarçay

Abstract:

The objective of this study is to investigate the feelings of health employees occurred by bullying and the relationships between these feelings at work place. In this context, the relationships between bullying and the feelings of self-esteem, employee silence, anger, self- blame and shame. This study was conducted among 512 health employees in three hospitals in Konya by using survey method and simple random sampling. The scales of bullying, self-esteem, employee silence, anger, self-blame, and shame were performed within the study. The obtained data were analyzed with descriptive analysis, correlation, confirmative factor analysis, structural equation modeling and path analysis. The results of the study showed that while bullying had a positive effect on self-esteem (.61), employee silence (.41), anger (.18), a negative effect on self-blame and shame (-.26) was observed. Employee silence affected self-blame and shame (.83) as positively. Besides, self-esteem impacted on self- blame and shame (.18), employee silence (.62) positively and self-blame and shame was observed as negatively affecting on anger (-.20). Similarly, self-esteem was found as negatively affected on anger (-.13).

Keywords: bullying, self-esteem, employee silence, anger, shame and guilt, healthcare employee

Procedia PDF Downloads 283
2851 A Semiotic Approach to the Construction of Classical Identity in Indian Classical Music Videos

Authors: Jayakrishnan Narayanan, Sengamalam Periyasamy Dhanavel

Abstract:

Indian classical (Karnatik) music videos across various media platforms have followed an audio-visual pattern that conforms to its socio-cultural and quasi-religious identity. The present paper analyzes the semiotic variations between ‘pure Karnatik music videos’ and ‘independent/contemporary-collaborative music videos’ posted on social media by young professional Karnatik musicians. The paper analyzes these media texts by comparing their various structural sememes namely, the title, artists, music, narrative schemata, visuals, lighting, sound, and costumes. The paper argues that the pure Karnatik music videos are marked by the presence of certain recurring mythological or third level signifiers and that these signifiers and codes are marked by their conspicuous absence in the independent music videos produced by the same musicians. While the music and the musical instruments used in both these sets of music videos remain similar, the meaning that is abducted by the beholder in each case is entirely different. The paper also attempts to study the identity conflicts that are projected through these music videos and the extent to which the cultural connotations of Karnatik music govern the production of its music videos.

Keywords: abduction, identity, media semiotics, music video

Procedia PDF Downloads 204
2850 Study on Flexible Diaphragm In-Plane Model of Irregular Multi-Storey Industrial Plant

Authors: Cheng-Hao Jiang, Mu-Xuan Tao

Abstract:

The rigid diaphragm model may cause errors in the calculation of internal forces due to neglecting the in-plane deformation of the diaphragm. This paper thus studies the effects of different diaphragm in-plane models (including in-plane rigid model and in-plane flexible model) on the seismic performance of structures. Taking an actual industrial plant as an example, the seismic performance of the structure is predicted using different floor diaphragm models, and the analysis errors caused by different diaphragm in-plane models including deformation error and internal force error are calculated. Furthermore, the influence of the aspect ratio on the analysis errors is investigated. Finally, the code rationality is evaluated by assessing the analysis errors of the structure models whose floors were determined as rigid according to the code’s criterion. It is found that different floor models may cause great differences in the distribution of structural internal forces, and the current code may underestimate the influence of the floor in-plane effect.

Keywords: industrial plant, diaphragm, calculating error, code rationality

Procedia PDF Downloads 130
2849 Determination of Stresses in Vlasov Beam Sections

Authors: Semih Erdogan

Abstract:

In this paper, the normal and shear stress distributions in Vlasov beams are determined by two-dimensional triangular finite element formulations. The proposed formulations take into account the warping effects along the beam axis. The shape of the considered beam sections may be arbitrary and varied throughout its length. The stiffness matrices and force vectors are derived for transversal forces, uniform torsion, and nonuniform torsion. The proposed finite element algorithm is validated by comparing the analytical solutions, structural engineering books, and related articles. The numerical examples include beams with different cross-section types such as solid, thick-walled, closed-thin-walled, and open-thin-walled sections. Materials defined in the examples are homogeneous, isotropic, and linearly elastic. Through these examples, the study demonstrates the capability of the proposed method to address a wide range of practical engineering scenarios.

Keywords: Vlasov beams, warping function, nonuniform torsion, finite element method, normal and shear stresses, cross-section properties

Procedia PDF Downloads 52
2848 Numerical Study on Ultimate Capacity of Bi-Modulus Beam-Column

Authors: Zhiming Ye, Dejiang Wang, Huiling Zhao

Abstract:

Development of the technology demands a higher-level research on the mechanical behavior of materials. Structural members made of bi-modulus materials have different elastic modulus when they are under tension and compression. The stress and strain states of the point effect on the elastic modulus and Poisson ratio of every point in the bi-modulus material body. Accompanied by the uncertainty and nonlinearity of the elastic constitutive relation is the complicated nonlinear problem of the bi-modulus members. In this paper, the small displacement and large displacement finite element method for the bi-modulus members have been proposed. Displacement nonlinearity is considered in the elastic constitutive equation. Mechanical behavior of slender bi-modulus beam-column under different boundary conditions and loading patterns has been simulated by the proposed method. The influence factors on the ultimate bearing capacity of slender beam and columns have been studied. The results show that as the ratio of tensile modulus to compressive modulus increases, the error of the simulation employing the same elastic modulus theory exceeds the engineering permissible error.

Keywords: bi-modulus, ultimate capacity, beam-column, nonlinearity

Procedia PDF Downloads 393
2847 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

Procedia PDF Downloads 183
2846 Optimization of Machining Parameters of Wire Electric Discharge Machining (WEDM) of Inconel 625 Super Alloy

Authors: Amitesh Goswami, Vishal Gulati, Annu Yadav

Abstract:

In this paper, WEDM has been used to investigate the machining characteristics of Inconel-625 alloy. The machining characteristics namely material removal rate (MRR) and surface roughness (SR) have been investigated along with surface microstructure analysis using SEM and EDS of the machined surface. Taguchi’s L27 Orthogonal array design has been used by considering six varying input parameters viz. Pulse-on time (Ton), Pulse-off time (Toff), Spark Gap Set Voltage (SV), Peak Current (IP), Wire Feed (WF) and Wire Tension (WT) for the responses of interest. It has been found out that Pulse-on time (Ton) and Spark Gap Set Voltage (SV) are the most significant parameters affecting material removal rate (MRR) and surface roughness (SR) are. Microstructure analysis of workpiece was also done using Scanning Electron Microscope (SEM). It was observed that, variations in pulse-on time and pulse-off time causes varying discharge energy and as a result of which deep craters / micro cracks and large/ small number of debris were formed. These results were helpful in studying the effects of pulse-on time and pulse-off time on MRR and SR. Energy Dispersive Spectrometry (EDS) was also done to check the compositional analysis of the material and it was observed that Copper and Zinc which were initially not present in the Inconel 625, later migrated on the material surface from the brass wire electrode during machining

Keywords: MRR, SEM, SR, taguchi, Wire Electric Discharge Machining

Procedia PDF Downloads 338
2845 Development of Dye Sensitized Solar Window by Physical Parameters Optimization

Authors: Tahsin Shameem, Chowdhury Sadman Jahan, Mohammad Alam

Abstract:

Interest about Net Zero Energy Buildings have gained traction in recent years following the need to sustain energy consumption with generations on site and to reduce dependence on grid supplied energy from large plants using fossil fuel. With this end in view, building integrated photovoltaics are being studied attempting to utilize all exterior facades of a building to generate power. In this paper, we have looked at the physical parameters defining a dye sensitized solar cell (DSSC) and discussed their impact on energy harvest. Following our discussion and experimental data obtained from literature, we have attempted to optimize these physical parameters accordingly so as to allow maximum light absorption for a given active layer thickness. We then modified a planer DSSC design with our optimized properties to allow adequate light transmission which demonstrated a high fill factor and an External Quantum Efficiency (EQE) of greater than 9% by computer aided design and simulation. In conclusion, a DSSC based solar window with such high output values even after such high light transmission through it definitely flags a promising future for this technology and our work elicits the need for further study and practical experimentation.

Keywords: net zero energy building, integrated photovoltaics, dye sensitized solar cell, fill factor, External Quantum Efficiency

Procedia PDF Downloads 124
2844 Prediction and Analysis of Human Transmembrane Transporter Proteins Based on SCM

Authors: Hui-Ling Huang, Tamara Vasylenko, Phasit Charoenkwan, Shih-Hsiang Chiu, Shinn-Ying Ho

Abstract:

The knowledge of the human transporters is still limited due to technically demanding procedure of crystallization for the structural characterization of transporters by spectroscopic methods. It is desirable to develop bioinformatics tools for effective analysis of available sequences in order to identify human transmembrane transporter proteins (HMTPs). This study proposes a scoring card method (SCM) based method for predicting HMTPs. We estimated a set of propensity scores of dipeptides to be HMTPs using SCM from the training dataset (HTS732) consisting of 366 HMTPs and 366 non-HMTPs. SCM using the estimated propensity scores of 20 amino acids and 400 dipeptides -as HMTPs, has a training accuracy of 87.63% and a test accuracy of 66.46%. The five top-ranked dipeptides include LD, NV, LI, KY, and MN with scores 996, 992, 989, 987, and 985, respectively. Five amino acids with the highest propensity scores are Ile, Phe, Met, Gly, and Leu, that hydrophobic residues are mostly highly-scored. Furthermore, obtained propensity scores were used to analyze physicochemical properties of human transporters.

Keywords: dipeptide composition, physicochemical property, human transmembrane transporter proteins, human transmembrane transporters binding propensity, scoring card method

Procedia PDF Downloads 358
2843 Structural Parameter Identification of Old Steel Truss Bridges

Authors: A. Bogdanovic, M. Vitanova, J. Bojadjieva, Z. Rakicevic, V. Sesov, K. Edip, N. Naumovski, F. Manojlovski, A.Popovska, A. Shoklarovski, T. Kitanovski, D. Ivanovski, I. Markovski, D. Filipovski

Abstract:

The conditions of existing structures change in the course of time and can hardly be characterized particularly if a bridge has long been in function and there is no design documentation related to it. To define the real conditions of a structure, detailed static and dynamic analysis of the structure has to be carried out and its modal parameters have to be defined accurately. Modal analysis enables a quite accurate identification of the natural frequencies and mode shapes. Presented in this paper are the results from the performed detailed analyses of a steel truss bridge that has been in use for more than 7 decades by the military services of R.N. Macedonia and for which there is no documentation at all. Static and dynamic investigations and ambient vibration measurements were performed. The acquired data were used to identify the mode shapes that were used for comparison with the numerical model. Dynamic tests were performed to define the bridge behaviour and the damping index. Finally, based on all the conducted detailed analyses and investigations, conclusions on the conditions of the bridge structure were drawn.

Keywords: ambient vibrations, dynamic identification, in-situ measurement, steel truss bridge

Procedia PDF Downloads 75
2842 Testing Plastic-Sand Construction Blocks Made from Recycled Polyethylene Terephthalate (rPET)

Authors: Cassi Henderson, Lucia Corsini, Shiv Kapila, Egle Augustaityte, Tsemaye Uwejamomere Zinzan Gurney, Aleyna Yildirim

Abstract:

Plastic pollution is a major threat to human and planetary health. In Low- and Middle-Income Countries, plastic waste poses a major problem for marginalized populations who lack access to formal waste management systems. This study explores the potential for converting waste plastic into construction blocks. It is the first study to analyze the use of polyethylene terephthalate (PET) as a binder in plastic-sand bricks. Unlike previous studies of plastic sand-bricks, this research tests the properties of bricks that were made using a low-cost kiln technology that was co-designed with a rural, coastal community in Kenya.  The mechanical strength, resistance to fire and water absorption properties of the bricks are tested in this study. The findings show that the bricks meet structural standards for mechanical performance, fire resistance and water absorption. It was found that 30:70 PET to sand demonstrated the best overall performance.

Keywords: recycling, PET, plastic, sustainable construction, sustainable development

Procedia PDF Downloads 110
2841 Extending the Theory of Planned Behaviour to Predict Intention to Commute by Bicycle: Case Study of Mexico City

Authors: Magda Cepeda, Frances Hodgson, Ann Jopson

Abstract:

There are different barriers people face when choosing to cycle for commuting purposes. This study examined the role of psycho-social factors predicting the intention to cycle to commute in Mexico City. An extended version of the theory of planned behaviour was developed and utilized with a simple random sample of 401 road users. We applied exploratory and confirmatory factor analysis and after identifying five factors, a structural equation model was estimated to find the relationships among the variables. The results indicated that cycling attributes, attitudes to cycling, social comparison and social image and prestige were the most important factors influencing intention to cycle. Although the results from this study are specific to Mexico City, they indicate areas of interest to transportation planners in other regions especially in those cities where intention to cycle its linked to its perceived image and there is political ambition to instigate positive cycling cultures. Moreover, this study contributes to the current literature developing applications of the Theory of Planned Behaviour.

Keywords: cycling, latent variable model, perception, theory of planned behaviour

Procedia PDF Downloads 340
2840 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
2839 Design and Validation of a Darrieus Type Hydrokinetic Turbine for South African Irrigation Canals Experimentally and Computationally

Authors: Maritz Lourens Van Rensburg, Chantel Niebuhr

Abstract:

Utilizing all available renewable energy sources is an ever-growing necessity, this includes a newfound interest into hydrokinetic energy systems, which open the door to installations where conventional hydropower shows no potential. Optimization and obtaining high efficiencies are key in these installations. In this study a vertical axis Darrieus hydrokinetic turbine is designed and constructed to address certain drawbacks experience by axial flow horizontal axis turbines in an irrigation channel. Many horizontal axis turbines have been well developed and optimized to have high efficiencies but depending on the conditions experienced in an open channel, the performance of these turbines may be adversely affected. The study analyses how the designed vertical axis turbine addresses the problems experienced by a horizontal axis turbine while still achieving a satisfactory efficiency. To be able to optimize the vertical axis turbine, a computational fluid dynamics model was validated to the experimental results obtained from the power generated from a test turbine installation operating at various rotational speeds. It was found that an accurate validated model can be obtained through validation of generated power output.

Keywords: hydrokinetic, Darrieus, computational fluid dynamics, vertical axis turbine

Procedia PDF Downloads 102
2838 The Effects of Social Capital and Empowering Leadership on Team Cohesion

Authors: Y. R. Lai, J. C. Jehng, T. T. Chang

Abstract:

Team is a popular job design in the management settings. Because people on a team need to work together to complete a lot of tasks, the interaction between team members strongly influences team effectiveness. The study examines the effect of social capital and empowering leadership on team cohesion. There are three facets of social capital: structural facet, relational facet, and cognitive facet. Empowering leadership includes enhancing the meaningfulness of work, fostering participation in decision making, expressing confidence in high performance, and providing autonomy from bureaucratic constraints. Data were collected from 181 team members of 47 teams in the real estate agency industry. The results show that the relational social capital, enhancing the meaningfulness of work, and providing autonomy from bureaucratic constraints are positively related to two dimensions of team cohesion: sense of belonging and feelings of moral. Additionally, expressing confidence in high performance is negatively related to sense of belonging.

Keywords: social capital, empowering leadership, team cohesion, team effectiveness

Procedia PDF Downloads 400
2837 Investigation of Steel-Concrete Composite Bridges under Blasting Loads Based on Slope Reflection

Authors: Yuan Li, Yitao Han, Zhao Zhu

Abstract:

In this paper, the effect of blasting loads on steel-concrete composite bridges has been investigated considering the slope reflection effect. Reasonable values of girder size, plate thickness, stiffening rib, and other design parameters were selected according to design specifications. Modified RHT (Riedel-Hiermaier-Thoma) was used as constitutive relation in analyses. In order to simulate the slope reflection effect, the slope of the bridge was precisely built in the model. Different blasting conditions, including top, middle, and bottom explosions, were simulated. The multi-Euler domain method based on fully coupled Lagrange and Euler models was adopted for the structural analysis of the explosion process using commercial software AUTODYN. The obtained results showed that explosion overpressure was increased by 3006, 879, and 449kPa, corresponding to explosions occurring at the top, middle, and bottom of the slope, respectively. At the same time, due to energy accumulation and transmission dissipation caused by slope reflection, the corresponding yield lengths of steel beams were increased by 8, 0, and 5m, respectively.

Keywords: steel-concrete composite bridge, explosion damage, slope reflection, blasting loads, RHT

Procedia PDF Downloads 81
2836 Strength of the Basement Wall Combined with a Temporary Retaining Wall for Excavation

Authors: Soo-yeon Seo, Su-jin Jung

Abstract:

In recent years, the need for remodeling of many apartments built 30 years ago is increasing. Therefore, researches on the structural reinforcement technology of existing apartments have been conducted. On the other hand, there is a growing need for research on the existing underground space expansion technology to expand the parking space required for remodeling. When expanding an existing underground space, for earthworks, an earth retaining wall must be installed between the existing apartment building and it. In order to maximize the possible underground space, it is necessary to minimize the thickness of the portion of earth retaining wall and underground basement wall. In this manner, the calculation procedure is studied for the evaluation of shear strength of the composite basement wall corresponding to shear span-to-depth ratio in this study. As a result, it was shown that the proposed calculation procedure can be used to evaluate the shear strength of the composite basement wall as safe. On the other hand, when shear span-to-depth ratio is small, shear strength is very underestimated.

Keywords: underground space expansion, combined structure, temporary retaining wall, basement wall, shear connectors

Procedia PDF Downloads 128
2835 Behaviour and Design of the Candle-Loc Inter-Module Connection in High-Rise Modular Buildings under Seismic Action

Authors: Alessandro Marzucchini, Yie Sue Chua, Andrew Lian, Richard Shonn Mills

Abstract:

A unique, fast and easy installed inter-module connection named Candle-Loc was developed and applied in several high-rise steel and reinforced concrete modular buildings in Singapore and Hong Kong, China. However, its effect on the global behaviour of modular buildings in high seismic zones was not studied. Therefore, the design concept and the structural performance of each component in this connection was investigated through analytical approach. Response spectrum, linear time-history, and nonlinear time-history analyses were conducted to investigate the effects of the different joint models of the Candle-Loc in the global analysis of high-rise buildings under high seismic loads. It is found that it is important to assess the level of plasticity developed in the inter-module connection under high seismic loads. The ductility of the lateral force resisting system influences the amount of load taken by the inter-module connections.

Keywords: high-rise, inter-module connection, nonlinear, seismic, time-history analysis

Procedia PDF Downloads 148
2834 Knowledge Sharing within a Team: Exploring the Antecedents and Role of Trust

Authors: Li Yan Hei, Au Wing Tung

Abstract:

Knowledge sharing is a process in which individuals mutually exchange existing knowledge and co-create new knowledge. Previous research has confirmed that trust is positively associated with knowledge sharing. However, only few studies systematically examined the antecedents of trust and these antecedents’ impacts on knowledge sharing. In order to explore and understand the relationships between trust and knowledge sharing in depth, this study proposed a relationship maintenance-based model to examine the antecedents of trust in knowledge sharing in project teams. Three critical elements within a project team were measured, including the environment, project team partner and interaction. It was hypothesized that the trust would lead to knowledge sharing and in turn result in perceived good team performance. With a sample of 200 Hong Kong employees, the proposed model was evaluated with structural equation modeling. Expected findings are trust will contribute to knowledge sharing, resulting in better team performance. The results will also offer insights into antecedents of trust that play a heavy role in the focal relationship. The present study contributes to a more holistic understanding of relationship between trust and knowledge sharing by linking the antecedents and outcomes. The findings will raise the awareness of project managers on ways to promote knowledge sharing.

Keywords: knowledge sharing, project management, team, trust

Procedia PDF Downloads 599
2833 Relevance Feedback within CBIR Systems

Authors: Mawloud Mosbah, Bachir Boucheham

Abstract:

We present here the results for a comparative study of some techniques, available in the literature, related to the relevance feedback mechanism in the case of a short-term learning. Only one method among those considered here is belonging to the data mining field which is the K-Nearest Neighbours Algorithm (KNN) while the rest of the methods is related purely to the information retrieval field and they fall under the purview of the following three major axes: Shifting query, Feature Weighting and the optimization of the parameters of similarity metric. As a contribution, and in addition to the comparative purpose, we propose a new version of the KNN algorithm referred to as an incremental KNN which is distinct from the original version in the sense that besides the influence of the seeds, the rate of the actual target image is influenced also by the images already rated. The results presented here have been obtained after experiments conducted on the Wang database for one iteration and utilizing colour moments on the RGB space. This compact descriptor, Colour Moments, is adequate for the efficiency purposes needed in the case of interactive systems. The results obtained allow us to claim that the proposed algorithm proves good results; it even outperforms a wide range of techniques available in the literature.

Keywords: CBIR, category search, relevance feedback, query point movement, standard Rocchio’s formula, adaptive shifting query, feature weighting, original KNN, incremental KNN

Procedia PDF Downloads 267
2832 Nanocharacterization of PIII Treated 7075 Aluminum Alloy

Authors: Bruno Bacci Fernandes, Stephan Mändl, Ataíde Ribeiro da Silva Junior, José Osvaldo Rossi, Mário Ueda

Abstract:

Nitrogen implantation in aluminum and its alloys is acquainted for the difficulties in obtaining modified layers deeper than 200 nm. The present work addresses a new method to overcome such a problem; although, the coating with nitrogen and oxygen obtained by plasma immersion ion implantation (PIII) into a 7075 aluminum alloy surface was too shallow. This alloy is commonly used for structural parts in aerospace applications. Such a layer was characterized by secondary ion mass spectroscopy, electron microscopy, and nanoindentation experiments reciprocating wear tests. From the results, one can assume that the wear of this aluminum alloy starts presenting severe abrasive wear followed by an additional adhesive mechanism. PIII produced a slight difference, as shown in all characterizations carried out in this work. The results shown here can be used as the scientific basis for further nitrogen PIII experiments in aluminum alloys which have the goal to produce thicker modified layers or to improve their surface properties.

Keywords: aluminum alloys, plasma immersion ion implantation, tribological properties, hardness, nanofatigue

Procedia PDF Downloads 325
2831 Seismic Fragility Functions of RC Moment Frames Using Incremental Dynamic Analyses

Authors: Seung-Won Lee, JongSoo Lee, Won-Jik Yang, Hyung-Joon Kim

Abstract:

A capacity spectrum method (CSM), one of methodologies to evaluate seismic fragilities of building structures, has been long recognized as the most convenient method, even if it contains several limitations to predict the seismic response of structures of interest. This paper proposes the procedure to estimate seismic fragility curves using an incremental dynamic analysis (IDA) rather than the method adopting a CSM. To achieve the research purpose, this study compares the seismic fragility curves of a 5-story reinforced concrete (RC) moment frame obtained from both methods, an IDA method and a CSM. Both seismic fragility curves are similar in slight and moderate damage states whereas the fragility curve obtained from the IDA method presents less variation (or uncertainties) in extensive and complete damage states. This is due to the fact that the IDA method can properly capture the structural response beyond yielding rather than the CSM and can directly calculate higher mode effects. From these observations, the CSM could overestimate seismic vulnerabilities of the studied structure in extensive or complete damage states.

Keywords: seismic fragility curve, incremental dynamic analysis, capacity spectrum method, reinforced concrete moment frame

Procedia PDF Downloads 411
2830 Particle Size Analysis of Itagunmodi Southwestern Nigeria Alluvial Gold Ore Sample by Gaudin Schumann Method

Authors: Olaniyi Awe, Adelana R. Adetunji, Abraham Adeleke

Abstract:

Mining of alluvial gold ore by artisanal miners has been going on for decades at Itagunmodi, Southwestern Nigeria. In order to optimize the traditional panning gravity separation method commonly used in the area, a mineral particle size analysis study is critical. This study analyzed alluvial gold ore samples collected at identified five different locations in the area with a view to determine the ore particle size distributions. 500g measured of as-received alluvial gold ore sample was introduced into the uppermost sieve of an electrical sieve shaker consisting of sieves arranged in the order of decreasing nominal apertures of 5600μm, 3350μm, 2800μm, 355μm, 250μm, 125μm and 90μm, and operated for 20 minutes. The amount of material retained on each sieve was measured and tabulated for analysis. A screen analysis graph using the Gaudin Schuman method was drawn for each of the screen tests on the alluvial samples. The study showed that the percentages of fine particle size -125+90 μm fraction were 45.00%, 36.00%, 39.60%, 43.00% and 36.80% for the selected samples. These primary ore characteristic results provide reference data for the alluvial gold ore processing method selection, process performance measurement and optimization.

Keywords: alluvial gold ore, sieve shaker, particle size, Gaudin Schumann

Procedia PDF Downloads 29
2829 Intrusion Detection in Computer Networks Using a Hybrid Model of Firefly and Differential Evolution Algorithms

Authors: Mohammad Besharatloo

Abstract:

Intrusion detection is an important research topic in network security because of increasing growth in the use of computer network services. Intrusion detection is done with the aim of detecting the unauthorized use or abuse in the networks and systems by the intruders. Therefore, the intrusion detection system is an efficient tool to control the user's access through some predefined regulations. Since, the data used in intrusion detection system has high dimension, a proper representation is required to show the basis structure of this data. Therefore, it is necessary to eliminate the redundant features to create the best representation subset. In the proposed method, a hybrid model of differential evolution and firefly algorithms was employed to choose the best subset of properties. In addition, decision tree and support vector machine (SVM) are adopted to determine the quality of the selected properties. In the first, the sorted population is divided into two sub-populations. These optimization algorithms were implemented on these sub-populations, respectively. Then, these sub-populations are merged to create next repetition population. The performance evaluation of the proposed method is done based on KDD Cup99. The simulation results show that the proposed method has better performance than the other methods in this context.

Keywords: intrusion detection system, differential evolution, firefly algorithm, support vector machine, decision tree

Procedia PDF Downloads 71
2828 Provotyping Futures Through Design

Authors: Elisabetta Cianfanelli, Maria Claudia Coppola, Margherita Tufarelli

Abstract:

Design practices throughout history return a critical understanding of society since they always conveyed values and meanings aimed at (re)framing reality by acting in everyday life: here, design gains cultural and normative character, since its artifacts, services, and environments hold the power to intercept, influence and inspire thoughts, behaviors, and relationships. In this sense, design can be persuasive, engaging in the production of worlds and, as such, acting in the space between poietics and politics so that chasing preferable futures and their aesthetic strategies becomes a matter full of political responsibility. This resonates with contemporary landscapes of radical interdependencies challenging designers to focus on complex socio-technical systems and to better support values such as equality and justice for both humans and nonhumans. In fact, it is in times of crisis and structural uncertainty that designers turn into visionaries at the service of society, envisioning scenarios and dwelling in the territories of imagination to conceive new fictions and frictions to be added to the thickness of the real. Here, design’s main tasks are to develop options, to increase the variety of choices, to cultivate its role as scout, jester, agent provocateur for the public, so that design for transformation emerges, making an explicit commitment to society, furthering structural change in a proactive and synergic manner. However, the exploration of possible futures is both a trap and a trampoline because, although it embodies a radical research tool, it raises various challenges when the design process goes further in the translation of such vision into an artefact - whether tangible or intangible -, through which it should deliver that bit of future into everyday experience. Today designers are making up new tools and practices to tackle current wicked challenges, combining their approaches with other disciplinary domains: futuring through design, thus, rises from research strands like speculative design, design fiction, and critical design, where the blending of design approaches and futures thinking brings an action-oriented and product-based approach to strategic insights. The contribution positions at the intersection of those approaches, aiming at discussing design’s tools of inquiry through which it is possible to grasp the agency of imagined futures into present time. Since futures are not remote, they actively participate in creating path-dependent decisions, crystallized into designed artifacts par excellence, prototypes, and their conceptual other, provotypes: with both being unfinished and multifaceted, the first ones are effective in reiterating solutions to problems already framed, while the second ones prove to be useful when the goal is to explore and break boundaries, bringing closer preferable futures. By focusing on some provotypes throughout history which challenged markets and, above all, social and cultural structures, the contribution’s final aim is understanding the knowledge produced by provotypes, understood as design spaces where designs’s humanistic side might help developing a deeper sensibility about uncertainty and, most of all, the unfinished feature of societal artifacts, whose experimentation would leave marks and traces to build up f(r)ictions as vital sparks of plurality and collective life.

Keywords: speculative design, provotypes, design knowledge, political theory

Procedia PDF Downloads 117
2827 Teachers’ Personal and Professional Characteristics: How They Relate to Teacher-Student Relationships and Students’ Behavior

Authors: Maria Poulou

Abstract:

The study investigated how teachers’ self-rated Emotional Intelligence (EI), competence in implementing Social and Emotional Learning (SEL) skills and teaching efficacy relate to teacher-student relationships and students’ emotional and behavioral difficulties. Participants were 98 elementary teachers from public schools in central Greece. They completed the Self-Rated Emotional Intelligence Scale (SREIS), the Teacher SEL Beliefs Scale, the Teachers’ Sense of Efficacy Scale (TSES), the Student-Teacher Relationships Scale-Short Form (STRS-SF) and the Strengths and Difficulties Questionnaire (SDQ) for 617 of their students, aged 6-11 years old. Structural equation modeling was used to examine an exploratory model of the variables. It was demonstrated that teachers’ emotional intelligence, SEL beliefs and teaching efficacy were significantly related to teacher-student relationships, but they were not related to students’ emotional and behavioral difficulties. Rather, teachers’ perceptions of teacher-students relationships were significantly related to these difficulties. These findings and their implications for research and practice are discussed.

Keywords: emotional intelligence, social and emotional learning, teacher-student relationships, teaching efficacy

Procedia PDF Downloads 422
2826 Conception of a Regulated, Dynamic and Intelligent Sewerage in Ostrevent

Authors: Rabaa Tlili Yaakoubi, Hind Nakouri, Olivier Blanpain

Abstract:

The current tools for real time management of sewer systems are based on two software tools: the software of weather forecast and the software of hydraulic simulation. The use of the first ones is an important cause of imprecision and uncertainty, the use of the second requires temporal important steps of decision because of their need in times of calculation. This way of proceeding fact that the obtained results are generally different from those waited. The major idea of the CARDIO project is to change the basic paradigm by approaching the problem by the "automatic" face rather than by that "hydrology". The objective is to make possible the realization of a large number of simulations at very short times (a few seconds) allowing to take place weather forecasts by using directly the real time meditative pluviometric data. The aim is to reach a system where the decision-making is realized from reliable data and where the correction of the error is permanent. A first model of control laws was realized and tested with different return-period rainfalls. The gains obtained in rejecting volume vary from 40 to 100%. The development of a new algorithm was then used to optimize calculation time and thus to overcome the subsequent combinatorial problem in our first approach. Finally, this new algorithm was tested with 16- year-rainfall series. The obtained gains are 60% of total volume rejected to the natural environment and of 80 % in the number of discharges.

Keywords: RTC, paradigm, optimization, automation

Procedia PDF Downloads 270
2825 From Modelled Design to Reality through Material and Machinery Lab and Field Tests: Porous Concrete Carparks at the Wanda Metropolitano Stadium in Madrid

Authors: Manuel de Pazos-Liano, Manuel Cifuentes-Antonio, Juan Fisac-Gozalo, Sara Perales-Momparler, Carlos Martinez-Montero

Abstract:

The first-ever game in the Wanda Metropolitano Stadium, the new home of the Club Atletico de Madrid, was played on September 16, 2017, thanks to the work of a multidisciplinary team that made it possible to combine urban development with sustainability goals. The new football ground sits on a 1.2 km² land owned by the city of Madrid. Its construction has dramatically increased the sealed area of the site (transforming the runoff coefficient from 0.35 to 0.9), and the surrounding sewer network has no capacity for that extra flow. As an alternative to enlarge the existing 2.5 m diameter pipes, it was decided to detain runoff on site by means of an integrated and durable infrastructure that would not blow up the construction cost nor represent a burden on the municipality’s maintenance tasks. Instead of the more conventional option of building a large concrete detention tank, the decision was taken on the use of pervious pavement on the 3013 car parking spaces for sub-surface water storage, a solution aligned with the city water ordinance and the Madrid + Natural project. Making the idea a reality, in only five months and during the summer season (which forced to pour the porous concrete only overnight), was a challenge never faced before in Spain, that required of innovation both at the material as well as the machinery side. The process consisted on: a) defining the characteristics required for the porous concrete (compressive strength of 15 N/mm2 and 20% voids); b) testing of different porous concrete dosages at the construction company laboratory; c) stablishing the cross section in order to provide structural strength and sufficient water detention capacity (20 cm porous concrete over a 5 cm 5/10 gravel, that sits on a 50 cm coarse 40/50 aggregate sub-base separated by a virgin fiber polypropylene geotextile fabric); d) hydraulic computer modelling (using the Full Hydrograph Method based on the Wallingford Procedure) to estimate design peak flows decrease (an average of 69% at the three car parking lots); e) use of a variety of machinery for the application of the porous concrete to achieve both structural strength and permeable surface (including an inverse rotating rolling imported from USA, and the so-called CMI, a sliding concrete paver used in the construction of motorways with rigid pavements); f) full-scale pilots and final construction testing by an accredited laboratory (pavement compressive strength average value of 15 N/mm2 and 0,0032 m/s permeability). The continuous testing and innovating construction process explained in detail within this article, allowed for a growing performance with time, finally proving the use of the CMI valid also for large porous car park applications. All this process resulted in a successful story that converts the Wanda Metropolitano Stadium into a great demonstration site that will help the application of the Spanish Royal Decree 638/2016 (it also counts with rainwater harvesting for grass irrigation).

Keywords: construction machinery, permeable carpark, porous concrete, SUDS, sustainable develpoment

Procedia PDF Downloads 129