Search results for: linear eigenvalue analysis

Authors: Guillermo Cardoso-Landa, Ana Julita Cuenca-Castro

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The present paper focuses to research the possible causes of curtain failure of dam "El Batan" in Querétaro, Mexico, including the design of the fineness of the employee filter during the construction of the curtain was verified since this depends greatly on the proper functioning of this filter. To carry out the required analysis, it was necessary to document elements provided understanding about the composition and behavior of the land curtain, and the main types of failure in these curtains. The general characteristics of the curtain dam "El Batan", the composition of the filter, as well as possible causes resulted in the failure were also analyzed. Once obtained data starting, the actual analysis was carried out by reviewing the following possible causes of failure: fails due to a poor constructive process of the curtain, failure due to hydraulic suppression, fails due to a structural design wrong, fails due to a geotechnical design wrong, fails due to a hydraulic design wrong, fails due to an inadequate design of the curtain filter. It is concluded that the type of the filter employed in the land dam curtain of "El Batan", located in the municipality of Querétaro, México, do not have adequate characteristics, outside of the ranges of design, using the curves: Terzaghi criteria, Sherard and Dunnigan criteria, UCSCS criteria, and Foster and Fell criteria.

Keywords: failure, dam, filter, curtain

Procedia PDF Downloads 502

Authors: Omar A. Abuobidalla, Mingyuan Chen, Satyaveer S. Chauhan

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Railroad transportation of hazardous materials freights is important to the North America economics that supports the national’s supply chain. This paper introduces various extensions of the dynamic hazardous materials trip plan problems. The problem captures most of the operational features of a real-world railroad transportations systems that dynamically initiates a set of blocks and assigns each shipment to a single block path or multiple block paths. The dynamic hazardous materials trip plan policies have distinguishing features that are integrating the blocking plan, and the block activation decisions. We also present a non-linear mixed integer programming formulation for each variant and present managerial insights based on a hypothetical railroad network. The computation results reveal that the dynamic car scheduling policies are not only able to take advantage of the capacity of the network but also capable of diminishing the population, and environment risks by rerouting the active blocks along the least risky train services without sacrificing the cost advantage of the railroad. The empirical results of this research illustrate that the issue of integrating the blocking plan, and the train makeup of the hazardous materials freights must receive closer attentions.

Keywords: dynamic car scheduling, planning and scheduling hazardous materials freights, airborne hazardous materials, gaussian plume model, integrated blocking and routing plans, box model

Procedia PDF Downloads 208

Authors: Abbas Shafiee, Mohammad Taghi Ahmadian, Maryam Hoviattalab

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The biomechanical behavior of brain tissue is needed for predicting the traumatic brain injury (TBI). Each year over 1.5 million people sustain a TBI in the USA. The appropriate coefficients for injury prediction can be evaluated using experimental data. In this study, an experimental setup on brain soft tissue was developed to perform unconfined compression tests at quasistatic strain rates ∈0.0004 s-1 and 0.008 s-1 and 0.4 stress relaxation test under unconfined uniaxial compression with ∈ 0.67 s-1 ramp rate. The fitted visco-hyperelastic parameters were utilized by using obtained stress-strain curves. The experimental data was validated using finite element analysis (FEA) and previous findings. Also, influence of friction coefficient on unconfined compression and relaxation test and effect of ramp rate in relaxation test is investigated. Results of the findings are implemented on the analysis of a human brain under high acceleration due to impact.

Keywords: brain soft tissue, visco-hyperelastic, finite element analysis (FEA), friction, quasistatic strain rate

Procedia PDF Downloads 660

Authors: Essa Abrahim Abdulgader Saleem, Thien-My Dao

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The main objective of this paper is to optimize series-parallel system reliability using Genetic Algorithm (GA) and statistical analysis; considering system reliability constraints which involve the redundant numbers of selected components, total cost, and total weight. To perform this work, firstly the mathematical model which maximizes system reliability subject to maximum system cost and maximum system weight constraints is presented; secondly, a statistical analysis is used to optimize GA parameters, and thirdly GA is used to optimize series-parallel systems reliability. The objective is to determine the strategy choosing the redundancy level for each subsystem to maximize the overall system reliability subject to total cost and total weight constraints. Finally, the series-parallel system case study reliability optimization results are showed, and comparisons with the other previous results are presented to demonstrate the performance of our GA.

Keywords: reliability, optimization, meta-heuristic, genetic algorithm, redundancy

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Authors: Mai Yen Nhi Doan, Viet Le, Chamindika Weerakoon

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Social enterprises have emerged as sustainable organisations that deliver social achievement along with long-term financial advancement. However, recorded financial barriers have urged social enterprises to divert to other financing methods due to the misaligned ideology with traditional financing capitalists, in which crowdfunding can be a promising alternative. Previous studies in crowdfunding have inadequately addressed crowdfunding for social enterprises, with conflicting results due to the unsuitable analysis of signals in isolation rather than in combinations, using the data from platforms that do not support social enterprises. Extending the signalling theory, this study suggests that crowdfunding success results from the collaboration between costly and costless signals. The proposed conceptual framework enlightens the interaction between costly signals as “organisational information”, “social entrepreneur’s credibility,” and “third-party endorsement” and costless signals as various sub-signals under the “campaign preparedness” signal to achieve crowdfunding success. Using Qualitative Comparative Analysis, this study examined 45 crowdfunding campaigns run by Australian social enterprises on StartSomeGood and Chuffed. The analysis found that different combinations of costly and costless signals can lead to crowdfunding success, allowing social enterprises to adopt suitable combinations of signals to their context. Costless signal – campaign preparedness is fundamental for success, though different costless sub-signals under campaign preparedness can interact with different costly signals for the desired outcome. Third-party endorsement signal was found to be the necessary signal for crowdfunding success for Australian social enterprises.

Keywords: crowdfunding, qualitative comparative analysis (QCA), signalling theory, social enterprises

Procedia PDF Downloads 110

Authors: Ramakrishna Rao Mamidi

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It is essential for Surface Mounted Permanent Magnet (SMPM) generators to determine the performance prediction and analyze the magnet’s air gap flux density wave shape. The flux density wave shape is neither a pure sine wave or square wave nor a combination. This is due to the variation of air gap reluctance between the stator and permanent magnets. The stator slot openings and the number of slots make the wave shape highly complicated. To reduce the complexity of analysis, approximations are made to the wave shape using Fourier analysis. In contrast to the traditional integration method, the Fourier coefficients, an and bn, are obtained by direct search method optimization. The wave shape with optimized coefficients gives a wave shape close to the desired wave shape. Harmonics amplitudes are worked out and compared with initial values. It can be concluded that the direct search method can be used for estimating Fourier coefficients for irregular wave shapes.

Keywords: direct search, flux plot, fourier analysis, permanent magnets

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Authors: C. B. Le, V. N. Pham

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In modern data analysis, multi-source data appears more and more in real applications. Multi-source data clustering has emerged as a important issue in the data mining and machine learning community. Different data sources provide information about different data. Therefore, multi-source data linking is essential to improve clustering performance. However, in practice multi-source data is often heterogeneous, uncertain, and large. This issue is considered a major challenge from multi-source data. Ensemble is a versatile machine learning model in which learning techniques can work in parallel, with big data. Clustering ensemble has been shown to outperform any standard clustering algorithm in terms of accuracy and robustness. However, most of the traditional clustering ensemble approaches are based on single-objective function and single-source data. This paper proposes a new clustering ensemble method for multi-source data analysis. The fuzzy optimized multi-objective clustering ensemble method is called FOMOCE. Firstly, a clustering ensemble mathematical model based on the structure of multi-objective clustering function, multi-source data, and dark knowledge is introduced. Then, rules for extracting dark knowledge from the input data, clustering algorithms, and base clusterings are designed and applied. Finally, a clustering ensemble algorithm is proposed for multi-source data analysis. The experiments were performed on the standard sample data set. The experimental results demonstrate the superior performance of the FOMOCE method compared to the existing clustering ensemble methods and multi-source clustering methods.

Keywords: clustering ensemble, multi-source, multi-objective, fuzzy clustering

Procedia PDF Downloads 195

Authors: Alimshan Faizulayev, Eralp Bektas, Abdul Ghafar Ismail, Bezhan Rustamov

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This paper performs empirical analysis on determinants of profitability in Islamic and Conventional Banks. The main focus of this study is to evaluate and measure of financial performance of Islamic banking firms operating in Egypt, Iran, Malaysia, Pakistan, Turkey, UAE in contrast to Conventional ones in those countries. To evaluate empirically performance of the banks, various financial ratios are employed. We measure performance in terms of liquidity, profitability, solvency, and efficiency. In this work, t-test, F-test, and OLS analysis are used to make hypothesis tests. Our findings reveal that there are similarities and differences in profitability determinants of Islamic and Conventional banking firms. The cost to revenue ratio has inverse relationship with profitability indicators in both banking systems. However, there are differences in financial performances between Conventional Banks and Islamic banks which are found in overall picture of all banks in terms of net income margin.

Keywords: Islamic banking, conventional banking, GDP growth, emerging market economies

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Authors: Claudia Borges Colcerniani

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The paper is about a qualitative study whose main objective is to know how labor, as a Brazilian constitutionally established social right, can promote the social inclusion of female heads of one-parent families in a situation of poverty. The participants are six women, mothers, and workers living in Rocinha, a community located in the city of Rio de Janeiro, RJ, Brazil. According to the Brazilian Federal Constitution, social rights are based on the idea that socioeconomic inequalities should not limit or eliminate civil and political rights. In this perspective, labor can be a way to reach social justice, according to the theory of Nancy Fraser, the theoretical framework adopted in this research. Data were collected through socioeconomic questionnaires, and semi-structured interviews applied individually. The results analysis was made using the content analysis/categorical content analysis, according to Bardin's perspective. The results indicate that labor (as a social right) is considered, by the interviewed women, as an opportunity for social inclusion when there are the characteristics of the formality in accordance with the international labor regulations (Decent Work - International Labour Organization/United Nations).

Keywords: female labor, social justice, inclusion, women, decent work

Procedia PDF Downloads 119

Authors: Mariam Matiashvili

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Argumentation is an integral part of our daily communications - formal or informal. Argumentative reasoning, techniques, and language tools are used both in personal conversations and in the business environment. Verbalization of the opinions requires the use of extraordinary syntactic-pragmatic structural quantities - arguments that add credibility to the statement. The study of argumentative structures allows us to identify the linguistic features that make the text argumentative. Knowing what elements make up an argumentative text in a particular language helps the users of that language improve their skills. Also, natural language processing (NLP) has become especially relevant recently. In this context, one of the main emphases is on the computational processing of argumentative texts, which will enable the automatic recognition and analysis of large volumes of textual data. The research deals with the linguistic analysis of the argumentative structures of Georgian political speeches - particularly the linguistic structure, characteristics, and functions of the parts of the argumentative text - claims, support, and attack statements. The research aims to describe the linguistic cues that give the sentence a judgmental/controversial character and helps to identify reasoning parts of the argumentative text. The empirical data comes from the Georgian Political Corpus, particularly TV debates. Consequently, the texts are of a dialogical nature, representing a discussion between two or more people (most often between a journalist and a politician). The research uses the following approaches to identify and analyze the argumentative structures Lexical Classification & Analysis - Identify lexical items that are relevant in argumentative texts creating process - Creating the lexicon of argumentation (presents groups of words gathered from a semantic point of view); Grammatical Analysis and Classification - means grammatical analysis of the words and phrases identified based on the arguing lexicon. Argumentation Schemas - Describe and identify the Argumentation Schemes that are most likely used in Georgian Political Speeches. As a final step, we analyzed the relations between the above mentioned components. For example, If an identified argument scheme is “Argument from Analogy”, identified lexical items semantically express analogy too, and they are most likely adverbs in Georgian. As a result, we created the lexicon with the words that play a significant role in creating Georgian argumentative structures. Linguistic analysis has shown that verbs play a crucial role in creating argumentative structures.

Keywords: georgian, argumentation schemas, argumentation structures, argumentation lexicon

Procedia PDF Downloads 76

Authors: Fatih Kılıç, Burak Birol, Necmettin Maraşlı

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The directional solidification process is generally used for homogeneous compound production, single crystal growth, and refining (zone refining), etc. processes. The most important two parameters that control eutectic structures are temperature gradient and grain growth rate which are called as solidification parameters The solidification behavior and microstructure characteristics is an interesting topic due to their effects on the properties and performance of the alloys containing eutectic compositions. The solidification behavior of multicomponent and multiphase systems is an important parameter for determining various properties of these materials. The researches have been conducted mostly on the solidification of pure materials or alloys containing two phases. However, there are very few studies on the literature about multiphase reactions and microstructure formation of multicomponent alloys during solidification. Because of this situation, it is important to study the microstructure formation and the thermodynamical, thermophysical and microstructural properties of these alloys. The production process is difficult due to easy oxidation of magnesium and therefore, there is not a comprehensive study concerning alloys containing high Mg (> 30 wt.% Mg). With the increasing amount of Mg inside Al alloys, the specific weight decreases, and the strength shows a slight increase, while due to formation of β-Al8Mg5 phase, ductility lowers. For this reason, production, examination and development of high Mg containing alloys will initiate the production of new advanced engineering materials. The original value of this research can be described as obtaining high Mg containing (> 30% Mg) Al based multicomponent alloys by melting under vacuum; controlled directional solidification with various growth rates at a constant temperature gradient; and establishing relationship between solidification rate and microstructural, mechanical, electrical and thermal properties. Therefore, within the scope of this research, some > 30% Mg containing ternary or quaternary Al alloy compositions were determined, and it was planned to investigate the effects of directional solidification rate on the mechanical, electrical and thermal properties of these alloys. Within the scope of the research, the influence of the growth rate on microstructure parameters, microhardness, tensile strength, electrical conductivity and thermal conductivity of directionally solidified high Mg containing Al-32,2Mg-0,37Si; Al-30Mg-12Zn; Al-32Mg-1,7Ni; Al-32,2Mg-0,37Fe; Al-32Mg-1,7Ni-0,4Si; Al-33,3Mg-0,35Si-0,11Fe (wt.%) alloys with wide range of growth rate (50-2500 µm/s) and fixed temperature gradient, will be investigated. The work can be planned as; (a) directional solidification of Al-Mg based Al-Mg-Si, Al-Mg-Zn, Al-Mg-Ni, Al-Mg-Fe, Al-Mg-Ni-Si, Al-Mg-Si-Fe within wide range of growth rates (50-2500 µm/s) at a constant temperature gradient by Bridgman type solidification system, (b) analysis of microstructure parameters of directionally solidified alloys by using an optical light microscopy and Scanning Electron Microscopy (SEM), (c) measurement of microhardness and tensile strength of directionally solidified alloys, (d) measurement of electrical conductivity by four point probe technique at room temperature (e) measurement of thermal conductivity by linear heat flow method at room temperature.

Keywords: directional solidification, electrical conductivity, high Mg containing multicomponent Al alloys, microhardness, microstructure, tensile strength, thermal conductivity

Procedia PDF Downloads 263

Authors: Shima Behkami, Nor Shahirul Umirah Idris, Sharifuddin Md. Zain, Kah Hin Low, Mehrdad Gholami, Nima A. Behkami, Ahmad Firdaus Kamaruddin

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In this work, Inductively Coupled Plasma Mass Spectrometry (ICP-MS), Isotopic Ratio Mass Spectrometry (IRMS) and Ultrasound Milko Tester were used to study milk samples obtained from various geographical locations in Malaysia. ICP-MS was used to determine the concentration of trace elements in milk, water and soil samples obtained from seven dairy farms at different geographical locations in peninsular Malaysia. IRMS was used to analyze the milk samples for isotopic ratios of δ13C, 15N and 18O. Nutritional parameters in the milk samples were determined using an ultrasound milko tester. Data obtained from these measurements were evaluated by Principal Component Analysis (PCA) and Hierarchical Analysis (HA) as a preliminary step in determining geographical origin of these milk samples. It is observed that the isotopic ratios and a number of the nutritional parameters are responsible for the discrimination of the samples. It was also observed that it is possible to determine the geographical origin of these milk samples solely by the isotopic ratios of δ13C, 15N and 18O. The accuracy of the geographical discrimination is demonstrated when several milk samples from a milk factory taken from one of the regions under study were appropriately assigned to the correct PCA cluster.

Keywords: inductively coupled plasma mass spectroscopy ICP-MS, isotope ratio mass spectroscopy IRMS, ultrasound, principal component analysis, hierarchical analysis, geographical origin, milk

Procedia PDF Downloads 373

Authors: Thoetchai Peeraphatdit, Peter A. Brady, Suraj Kapa, Samuel J. Asirvatham, Niyada Naksuk

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Background: Serum electrolyte abnormalities are a common cause of an acquired prolonged QT syndrome, especially, in the coronary care unit (CCU) setting. Optimal electrolyte ranges among the CCU patients have not been sufficiently investigated. Methods: We identified 8,498 consecutive CCU patients who were admitted to the CCU at Mayo Clinic, Rochester, the USA, from 2004 through 2013. Association between first serum electrolytes and baseline corrected QT intervals (QTc), as well as in-hospital mortality, was tested using multivariate linear regression and logistic regression, respectively. Serum potassium 4.0- < 4.5 mEq/L, ionized calcium (iCa) 4.6-4.8 mg/dL, and magnesium 2.0- < 2.2 mg/dL were used as the reference levels. Results: There was a modest level-dependent relationship between hypokalemia ( < 4.0 mEq/L), hypocalcemia ( < 4.4 mg/dL), and a prolonged QTc interval; serum magnesium did not affect the QTc interval. Association between the serum electrolytes and in-hospital mortality included a U-shaped relationship for serum potassium (adjusted odds ratio (OR) 1.53 and OR 1.91for serum potassium 4.5- < 5.0 and ≥ 5.0 mEq/L, respectively) and an inverted J-shaped relationship for iCa (adjusted OR 2.79 and OR 2.03 for calcium < 4.4 and 4.4- < 4.6 mg/dL, respectively). For serum magnesium, the mortality was greater only among patients with levels ≥ 2.4 mg/dL (adjusted OR 1.40), compared to the reference level. Findings were similar in sensitivity analyses examining the association between mean serum electrolytes and mean QTc intervals, as well as in-hospital mortality. Conclusions: Serum potassium 4.0- < 4.5 mEq/L, iCa ≥ 4.6 mg/dL, and magnesium < 2.4 mg/dL had a neutral effect on QTc intervals and were associated with the lowest in-hospital mortality among the CCU patients.

Keywords: calcium, electrocardiography, long-QT syndrome, magnesium, mortality, potassium

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Authors: Yanhua Ma, Lu Zhai, Xinchen Wang, Hongyu Liang

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In this paper, by understanding the development status of the human-machine interface in today's automobile cab, a subjective and objective evaluation system for evaluating the optimization of human-machine interface matching in automobile cab was established. The man-machine interface of the car cab was divided into a software interface and a hard interface. Objective evaluation method of software human factor analysis is used to evaluate the hard interface matching; The analytic hierarchy process is used to establish the evaluation index system for the software interface matching optimization, and the multi-level fuzzy comprehensive evaluation method is used to evaluate hard interface machine. This article takes Dongfeng Sokon (DFSK) C37 model automobile as an example. The evaluation method given in the paper is used to carry out relevant analysis and evaluation, and corresponding optimization suggestions are given, which have certain reference value for designers.

Keywords: analytic hierarchy process, fuzzy comprehension evaluation method, human-machine interface, matching optimization, software human factor analysis

Procedia PDF Downloads 160

Authors: M. Naeimi, H. Aghazadeh, E. Afjei, A. Siadatan

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In this paper, a novel view of air gap magnetic field analysis of synchronous reluctance motor and permanent magnet assisted synchronous reluctance motor under static eccentricity to provide the precise fault diagnosis based on three-dimensional finite element method is presented. Analytical nature of this method makes it possible to simulate reliable and precise model by considering the end effects and axial fringing effects. The results of the three-dimensional finite element analysis of synchronous reluctance motor and permanent magnet synchronous reluctance motor such as flux linkage, flux density, and compression both of SynRM and PM-SynRM for various eccentric motor conditions are obtained and analyzed. These results present useful information regarding to the detection of static eccentricity.

Keywords: synchronous reluctance motor (SynRM), permanent magnet assisted synchronous reluctance motor (PMaSynRM), finite element method, static eccentricity, fault analysis

Procedia PDF Downloads 317

Authors: Saw Thiha, Jay Rajasekera

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A boom in video conferencing generated millions of hours of video data daily to be analyzed. However, such enormous data pose certain scalability issues to be analyzed efficiently, let alone do it in real-time, as online conferences can involve hundreds of people and can last for hours. This paper proposes an efficient online proctoring solution that can analyze the online conferences real-time on edge devices such as Android, iOS, and desktops. Since the computation can be done upfront on the devices where online conferences take place, it can scale well without requiring intensive resources such as GPU servers and complex cloud infrastructure. According to the linear models, face orientation does indeed impact the perceived eye openness. Also, the proposed z score facial landmark standardization was proven to be functional in detecting face orientation and contributed to classifying eye blinks with single eyelid distance computation while achieving a better f1 score and accuracy than the Eye Aspect Ratio (EAR) threshold method. Last but not least, the authors implemented the solution natively in the MediaPipe framework and open-sourced it along with the reproducible experimental results on GitHub. The solution provides face orientation, eye blink, facial activity, and translation detections out of the box and is highly customizable and extensible.

Keywords: android, desktop, edge computing, blink, face orientation, facial activity and translation, MediaPipe, open source, real-time, video conference, web, iOS, Z score facial landmark standardization

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Authors: Sanja Šurdonja, Aleksandra Deluka-Tibljaš, Mirna Klobučar, Irena Ištoka Otković

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Roundabouts are a common choice in the case of reconstruction of an intersection, whether it is to improve the capacity of the intersection or traffic safety, especially in urban conditions. The regulation for the design of roundabouts is often related to driving culture, the tradition of using this type of intersection, etc. Individual values in the regulation are usually recommended in a wide range (this is the case in Croatian regulation), and the final design of a roundabout largely depends on the designer's experience and his/her choice of design elements. Therefore, before-after analyses are a good way to monitor the performance of roundabouts and possibly improve the recommendations of the regulation. This paper presents a comprehensive before-after analysis of a roundabout on the country road network near Rijeka, Croatia. The analysis is based on a thorough collection of traffic data (operating speeds and traffic load) and design elements data, both before and after the reconstruction into a roundabout. At the chosen location, the roundabout solution aimed to improve capacity and traffic safety. Therefore, the paper analyzed the collected data to see if the roundabout achieved the expected effect. A traffic microsimulation model (VISSIM) of the roundabout was created based on the real collected data, and the influence of the increase of traffic load and different traffic structures, as well as of the selected design elements on the capacity of the roundabout, were analyzed. Also, through the analysis of operating speeds and potential conflicts by application of the Surrogate Safety Assessment Model (SSAM), the traffic safety effect of the roundabout was analyzed. The results of this research show the practical value of before-after analysis as an indicator of roundabout effectiveness at a specific location. The application of a microsimulation model provides a practical method for analyzing intersection functionality from a capacity and safety perspective in present and changed traffic and design conditions.

Keywords: before-after analysis, operating speed, capacity, design.

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Authors: Gabriela-Andreea Despescu, Mădălina-Elena Mavrodin, Gheorghe Lăzăroiu, Florin Adrian Grădinaru

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The purpose of this paper is to contribute to the enhancement of a hydroelectric plant protection by coordinating protection measures and existing security and introducing new measures under a risk management process. Also, the plan identifies key critical elements of a hydroelectric plant, from its level vulnerabilities and threats it is subjected to in order to achieve the necessary protection measures to reduce the level of risk.

Keywords: critical infrastructure, risk analysis, critical infrastructure protection, vulnerability, risk management, turbine, impact analysis

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Authors: Sui Yan Wong, Keat Ping Yeoh, Chi Wai Hui

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In this study, supercritical steam is introduced to Combined Cycle Power Plant (CCPP) in an attempt to further optimize energy recovery. Subcritical steam is commonly used in the CCPP, operating at maximum pressures around 150-160 bar. Supercritical steam is an alternative to increase heat recovery during vaporization period of water. The idea of improvement using supercritical steam is further examined with the use of exergy, pinch analysis and Aspen Plus simulation.

Keywords: exergy, pinch, combined cycle power plant, supercritical steam

Procedia PDF Downloads 145

Authors: Khadiga Kahwa, Aniza Ismail

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Depression, anxiety, and stress are associated with decreased role functioning, productivity, and quality of life. International students are more prone to psychological distress as they face many stressors while studying abroad. The objectives of the study were to determine the prevalence and associated factors of depression, anxiety, and stress among international students, their help-seeking behavior, and their awareness of the available on-campus mental support services. A cross-sectional study with a purposive sampling method was performed on 280 international students at Universiti Kebangsaan Malaysia (UKM) between the age of 18 and 35 years. The Depression Anxiety Stress Scale-21 (DASS-21) questionnaire was used anonymously to assess the mental health of students. Socio-demographic, help-seeking behavior, and awareness data were obtained. Independent sample t-test, one-way ANOVA test, and multiple linear regression were used to explore associated factors. The overall prevalence of depression, anxiety, and stress among international students were 58.9%, 71.8%, and 53.9%, respectively. Age was significantly associated with depression and anxiety. Ethnicity showed a significant association with depression and stress. No other factors were found to be significantly associated with psychological distress. Only 9.6% of the international students had sought help from on-campus mental support services. Students who were aware of the presence of such services were only 21.4% of the participants. In conclusion, this study addressed the gap in the literature on the mental health of international students and provided data that could be used in intervention programs to improve the mental health of the increasing number of international students in Malaysia.

Keywords: anxiety, depression, stress, help-seeking behavior, students

Procedia PDF Downloads 137

Authors: Aderet M. Pantierer, Shmuel Pantierer, Raphael Cordina, Yougashwar Budhoo

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Stress concentration occurs when there is an abrupt change in geometry, a mechanical part under loading. These changes in geometry can include holes, notches, or cracks within the component. The modifications create larger stress within the part. This maximum stress is difficult to determine, as it is directly at the point of the minimum area. Strain gauges have yet to be developed to analyze stresses at such minute areas. Therefore, a stress concentration factor must be utilized. The stress concentration factor is a dimensionless parameter calculated solely on the geometry of a part. The factor is multiplied by the nominal, or average, stress of the component, which can be found analytically or experimentally. Stress concentration graphs exist for common loading conditions and geometrical configurations to aid in the determination of the maximum stress a part can withstand. These graphs were developed from historical data yielded from experimentation. This project seeks to verify a stress concentration graph for combined loading conditions. The aforementioned graph was developed using CATIA Finite Element Analysis software. The results of this analysis will be validated through further testing. The 3D modeled parts will be subjected to further finite element analysis using Patran-Nastran software. The finite element models will then be verified by testing physical specimen using a tensile testing machine. Once the data is validated, the unique stress concentration graph will be submitted for publication so it can aid engineers in future projects.

Keywords: stress concentration, finite element analysis, finite element models, combined loading

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Authors: Juan Bojórquez, Henry E. Reyes, Edén Bojórquez, Alfredo Reyes-Salazar

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This paper addressed the use of Artificial Intelligence to obtain the structural reliability of reinforced concrete buildings. For this purpose, artificial neuronal networks (ANN) are developed to predict seismic demand hazard curves. In order to have enough input-output data to train the ANN, a set of reinforced concrete buildings (low, mid, and high rise) are designed, then a probabilistic seismic hazard analysis is made to obtain the seismic demand hazard curves. The results are then used as input-output data to train the ANN in a feedforward backpropagation model. The predicted values of the seismic demand hazard curves found by the ANN are then compared. Finally, it is concluded that the computer time analysis is significantly lower and the predictions obtained from the ANN were accurate in comparison to the values obtained from the conventional methods.

Keywords: structural reliability, seismic design, machine learning, artificial neural network, probabilistic seismic hazard analysis, seismic demand hazard curves

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Authors: R. Harman Dwi, Ryan Avirsa, P. Abraham Ivan

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Understanding of temperatures in the past, present, and future temperatures can be possible to do by analysis abundance of fossil foraminifera. This research was conducted in Sambipitu Formation, Ngalang River, Nglipar, Gunung Kidul Regency. The research method is divided into 3 stages: 1) study of literature, research based on previous researchers, 2) spatial, observation and sampling every 5-10 meters, 3) descriptive, analyzing samples consisting of a 10-gram sample weight, washing sample using 30% peroxide, biostratigraphy analysis, paleotemperature analysis using abundance of fossil, diversity analysis using Simpson diversity index method, and comparing current temperature data. There are two phases based on the appearance of Globorotalia menardii and Pulleniatina obliqueculata pointed to Phase Tropical Area, and the appearance of fossil Globigerinoides ruber and Orbulina universa fossil shows the phase of Subtropical Area. Paleotemperatur based on the appearance of Globorotalia menardii, Globigerinoides trilobus, Globigerinoides ruber, Orbulina universa, and Pulleniatina obliqueculata pointed to Warm Water Area and Warm Water Area (average surface water approximate 25°C).

Keywords: abundance, biostratigraphy, Simpson diversity index method, paleotemperature

Procedia PDF Downloads 175

Authors: Faribaebrahimi, Mehdi Ghorbani, Mohsen Mohsenisaravi

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Ecosystem management is complex because of natural and human issues. To cope with this complexity water governance is recommended since it involves all stakeholders including people, governmental and non-governmental organization who related to environmental systems. Water governance emphasizes on water co-management through consideration of all the stakeholders in the form of social and organizational network. In this research, to illustrate indicators of water governance in Dorood watershed, in Shemiranat region of Iran, social network analysis had been applied. The results revealed that social cohesion among pastoralists in Dorood is medium because of trust links, while link sustainability is weak to medium. According to the results, some pastoralists have high social power and therefore are key actors in the utilization network, regarding to centrality index and trust links. The results also demonstrated that Agricultural Development Office and (Shemshak-Darbandsar Islamic) Council are key actors in rangeland co-management, based on centrality index in rangeland institutional network at regional scale in Shemiranat district.

Keywords: social network analysis, water governance, organizational network, water co-management

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Authors: Massoud Farag Abouklaish

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The main aim of the present study is to investigate and classify the particle size distribution of sandy soils in Libya. More than fifty soil samples collected from many regions in North, West and South of Libya. Laboratory sieve analysis tests performed on disturbed soil samples to determine grain size distribution. As well as to provide an indicator of general engineering behavior and good understanding, test results are presented and analysed. In addition, conclusions, recommendations are made.

Keywords: Libya, grain size, sandy soils, sieve analysis tests

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Authors: Chitaranjan Sharma

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The present paper deals with the analysis of a fuel supply system in an automobile engine of a four wheeler which is having both the option of fuel i.e. PETROL and CNG. Since CNG is cheaper than petrol so the priority is given to consume CNG as compared to petrol. An automatic switch is used to start petrol supply at the time of failure of CNG supply. Using regenerative point technique with Markov renewal process, the reliability characteristics which are useful to system designers are obtained.

Keywords: reliability, redundancy, repair time, transition, probability, regenerative points, markov renewal, process

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Authors: Shirin jalili, Hadi Shirzad, Samaneh Nabavi, Somayeh Khanjani

Abstract:

Biosensors in forensic analysis are ideal biological tools that can be used for rapid and sensitive initial screening and testing to detect of suspicious components like biological and chemical agent in crime scenes. The wide use of different biomolecules such as proteins, nucleic acids, microorganisms, antibodies and enzymes makes it possible. These biosensors have great advantages such as rapidity, little sample manipulation and high sensitivity, also Because of their stability, specificity and low cost they have become a very important tool to Forensic analysis and detection of crime. In crime scenes different substances such as rape samples, Semen, saliva fingerprints and blood samples, act as a detecting elements for biosensors. On the other hand, successful fluid recovery via biosensor has the propensity to yield a highly valuable source of genetic material, which is important in finding the suspect. Although current biological fluid testing techniques are impaired for identification of body fluids. But these methods have disadvantages. For example if they are to be used simultaneously, Often give false positive result. These limitations can negatively result the output of a case through missed or misinterpreted evidence. The use of biosensor enable criminal researchers the highly sensitive and non-destructive detection of biological fluid through interaction with several fluid-endogenous and other biological and chemical contamination at the crime scene. For this reason, using of the biosensors for detecting the biological fluid found at the crime scenes which play an important role in identifying the suspect and solving the criminal.

Keywords: biosensors, forensic analysis, biological fluid, crime detection

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Authors: Vijay Kumar Bajpai, Sudhir Kumar Singh

Abstract:

In this study, the performance analyses of the twenty five coal-fired power plants (CFPPs) used for electricity generation are carried out through various data envelopment analysis (DEA) models. Three efficiency indices are defined and pursued. During the calculation of the operational performance, energy and non-energy variables are used as input, and net electricity produced is used as desired output. CO2 emitted to the environment is used as the undesired output in the computation of the pure environmental performance while in Model-3 CO2 emissions is considered as detrimental input in the calculation of operational and environmental performance. Empirical results show that most of the plants are operating in increasing returns to scale region and Mettur plant is efficient one with regards to energy use and environment. The result also indicates that the undesirable output effect is insignificant in the research sample. The present study will provide clues to plant operators towards raising the operational and environmental performance of CFPPs.

Keywords: coal fired power plants, environmental performance, data envelopment analysis, operational performance

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Authors: Radovan Čobanović, Milica Rankov Šicar

Abstract:

In the modern bakery various supplements are used to attract more customers. Analyzed sample decorative toppings are consisted of flax seeds, corn grits, oatmeal, wheat flakes, sesame seeds, sunflower seeds, soybean sprouts are used as decoration for the bread. Our goal was to extend the product shelf life based on the analysis. According to the plan of sustainability it was defined that sample which already had expired shelf life had to be stored for 5 months at 25°C and analyzed every month from the day of reception until spoilage occurs. Samples were subjected to sensory analysis (appearance, odor, taste, color, and consistency), microbiological analysis (Salmonella spp., Bacillus cereus, Enterobacteriaceae and moulds) and chemistry analysis (free fatty acids (as oleic), peroxide number, water content and degree of acidity). All analyses were tested according: sensory analysis ISO 6658, Salmonella spp ISO 6579, Bacillus cereus ISO 7932, Enterobacteriaceae ISO 21528-2 and moulds ISO 21527-1, free fatty acids (as oleic) ISO 660, peroxide number ISO 3960, water content and degree of acidity Serbian ordinance on the methods of chemical analysis. After five months of storage, there had been the first changes concerning of sensory properties of the product. In the sample were visible worms and creations which look like spider nets linking seeds and cereal. The sample had smell on rancid and pungent. The results of microbiological analysis showed that Salmonella spp was not detected, Enterobacteriaceae were < 10 cfu/g during all 5 months but in fifth month Bacillus cereus and moulds occurred 700 cfu/g and 1500 cfu/g respectively. Chemical analyzes showed that the water content did not exceed a maximum of 14%. The content of free fatty acids ranged from 3.06 to 3.26%, degree of acidity from 3.69 to 4.9. With increasing degree of acidity the degradation of the sample and the activity of microorganisms was increased which led to the formation of acid reaction which is accompanied by the appearance of unpleasant odor and taste. Based on the obtained results it can be concluded that this product can have longer shelf life for four months than shelf life which is already defined because there are no changes that could have influence on decision of customers when purchase of this product is concerned.

Keywords: bakery products, extension of shelf life, sensory and chemical and microbiological analyses, sustainability

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Authors: Biruk Wolde Eremacho

Abstract:

The Kombolcha to Desse road, linking Addis Ababa with Northern Ethiopia towns traverses through one of the most difficult mountainous ranges in Ethiopia. The presence of loose unconsolidated materials (colluvium materials), highly weathered and fractured basalt rocks high relief, steep natural slopes, nature of geologic formations exposed along the road section, poor drainage conditions, occurrence of high seasonal rains, and seismically active nature of the region created favorable condition for slope instability in the area. Thus, keeping in mind all above points the present study was conceived to study in detail the slope stability condition of the area. It was realized that detailed slope stability studies along this road section are very necessary to identify critical slopes and to provide the best remedial measures to minimize the slope instability problems which frequently disrupt and endanger the traffic movement on this important road. For the present study based on the field manifestation of instability two most critical slope sections were identified for detailed slope stability analysis. The deterministic slope stability analysis approach was followed to perform the detailed slope stability analysis of the selected slope sections. Factor of safety for the selected slope sections was determined for the different anticipated conditions (i.e., static and dynamic with varied water saturations) using Slope/W and Slide software. Both static and seismic slope stability analysis were carried out and factor of safety was deduced for each anticipated conditions. In general, detailed slope stability analysis of the two critical slope sections reveals that for only static dry condition both the slopes sections would be stable. However, for the rest anticipated conditions defined by static and dynamic situations with varied water saturations both critical slope sections would be unstable. Moreover, the causes of slope instability in the study area are governed by different factors; therefore integrated approaches of remedial measures are more appropriate to mitigate the possible slope instability in the study area. Depending on site condition and slope stability analysis result four types of suitable preventive and remedial measures are recommended namely; proper managements of drainages, retaining structures, gabions, and managing steeply cut slopes.

Keywords: factor of safety, remedial measures, slope stability analysis, static and dynamic condition

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