Search results for: loading factor performance
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 18490

Search results for: loading factor performance

5500 Surface Roughness of AlSi/10%AlN Metal Matrix Composite Material Using the Taguchi Method

Authors: Nurul Na'imy Wan, Mohamad Sazali Said, Jaharah Ab. Ghani, Mohd Asri Selamat

Abstract:

This paper presents the surface roughness of the Aluminium silicon alloy (AlSi) matrix composite which has been reinforced with aluminium nitride (AlN), with three types of carbide inserts. Experiments were conducted at various cutting speeds, feed rates, and depths of cut, according to the Taguchi method, using a standard orthogonal array L27 (34). The signal-to-noise (S/N) ratio and analysis of variance are applied to study the characteristic performance of machining parameters in measuring the surface roughness during the milling operation. The analysis of results, using the Taguchi method concluded that a combination of low feed rate, medium depth of cut, low cutting speed, and insert TiB2 give a better value of surface roughness. From Taguchi method, it was found that cutting speed of 230m/min, feed rate of 0.4 mm/tooth, depth of cut of 0.5mm and type of insert of TiB2 were the optimal machining parameters that gave the optimal value of surface roughness.

Keywords: AlSi/AlN Metal Matrix Composite (MMC), surface roughness, Taguchi method

Procedia PDF Downloads 468
5499 Experimental Analysis of Control in Electric Vehicle Charging Station Based Grid Tied Photovoltaic-Battery System

Authors: A. Hassoune, M. Khafallah, A. Mesbahi, T. Bouragba

Abstract:

This work presents an improved strategy of control for charging a lithium-ion battery in an electric vehicle charging station using two charger topologies i.e. single ended primary inductor converter (SEPIC) and forward converter. In terms of rapidity and accuracy, the power system consists of a topology/control diagram that would overcome the performance constraints, for instance the power instability, the battery overloading and how the energy conversion blocks would react efficiently to any kind of perturbations. Simulation results show the effectiveness of the proposed topologies operated with a power management algorithm based on voltage/peak current mode controls. In order to provide credible findings, a low power prototype is developed to test the control strategy via experimental evaluations of the converter topology and its controls.

Keywords: battery storage buffer, charging station, electric vehicle, experimental analysis, management algorithm, switches control

Procedia PDF Downloads 169
5498 Cardiovascular Disease Data Analysis Using Machine Learning Models

Authors: Ranveet Saggu, Saad Bin Ahmed

Abstract:

Cardiovascular Disease (CVD) is the leading cause of death worldwide. One of its main manifestations, myocardial infarction (commonly known as a heart attack), occurs about 750,000 times a year, caused by insufficient blood flow to a portion of the heart muscle. A quick and accurate diagnosis of a heart attack or heart failure is crucial in the treatment of the patient. The aim of this research project is to improve the prediction of cardiovascular diseases by automating risk assessment using binary classifiers. The methodology includes Exploratory Data Analysis (EDA), which helps to obtain information about the dataset with the help of visualizations and metrics. Additionally, Feature Engineering techniques is employed to address missing values, outliers, feature extraction, and normalizing the dataset. Subsequently, various classification machine learning algorithms are trained, and their accuracy along with other metrics are evaluated to identify the most efficient model in terms of processing time and predictive performance.

Keywords: cardiovascular disease, machine learning, deci- sion trees, logistic regression, k-nearest neighbor, xgboost, random forest, gradient boosting

Procedia PDF Downloads 14
5497 A Systematic Review in the Impacts of Skilled Parent Migration on Left-Behind Children: Gaps in the Existing Knowledge

Authors: Yassir Mohammed

Abstract:

The study examines the impact of skilled parental migration on left-behind children. It uses the SCOPUS database to evaluate the existing literature from 1972 to 2022 and synthesizes data using the PRISMA framework and bibliometric method of analysis. 49 articles out of 202 papers were involved in the synthesis. International migration, outcome migration, consequence, parental migration, high-skill and left-behind children, and left-behind preschool were all searched. The research found that mental health issues, self-isolation, and physical harm have negative impacts, while sending children to good schools, having good academic records, and better medical care have positive impacts. The study also found that gender gaps increase in some countries while decreasing in others. Further research is needed on child maltreatment, academic performance, subjective well-being, societal effects, behavioral difficulties, and quality of life. The study only included peer-reviewed English publications in the final analysis.

Keywords: parental migration, impact of migration, systematic review, left-behind children

Procedia PDF Downloads 75
5496 Enterpreneurial Orientation Dimensions for Sustainable Development in Construction Firms

Authors: Kudirat I. Zakariyyah, Iniobong B. John, Julius O. Faremi, David Adio-Moses

Abstract:

One of the key contributors to firms’ growth, performance, and sustainability is entrepreneurial orientation (EO). Most studies on EO, however, are in other industries than construction and, more often, exploratory. The purpose of this study is thus to create an awareness on entrepreneurial orientation and its dimensions in contracting firms. Considering the need for sustainability, the study thus examined contracting firms’ entrepreneurial orientation dimensions that are required in order to keep pace with the demands for sustainable development. This was done by giving out questionnaires to a sample of 116 respondents from a population of 166 construction firms in Lagos state. Data were collected through a survey and analysed using mean scores and analysis of variance (ANOVA). The result revealed the prevalence of the four dimensions of EO, though in moderate proportion. In addition, the study identified review of organisational structure as the top entrepreneurial orientation dimension needed for sustainable development. The study concludes that the firms should identify the existing orientation dimensions and its relevance with sustainability so as to be able to know the required review that will be appropriate in the industry. It is recommended that the firms need to do more on raising the level of prevalence of the various orientation dimensions in order to achieve the merits of the different constructs of sustainability.

Keywords: construction, culture, entrepreneurial-orientation, dimension, sustainability

Procedia PDF Downloads 159
5495 Positive Thinking Reexamined: The Reality of the Role of Negativity & Emotions in the Pursuit of Goals

Authors: Lindsay Foreman

Abstract:

Introduction: Goals have become synonymous with the quest for the good life and the pursuit of happiness, with coaching and positive psychology gaining popularity as an approach in recent decades. And yet mental health is on the rise and the leading cause of disability, wellbeing is on the decline, stress is leading to 50-60% of workday absences and the need for action is indisputable and urgent. Purpose: The purpose of this study is to better understand two things we cannot see, but that play the most significant role in these outcomes - what we think and how we feel. With many working on the assumption that positive thinking and an optimistic outlook are necessary or valuable components of goal pursuit, this study uncovers the reality of the ‘inner-game’ from the coachees perspective. Method: With a mixed methods design using a Q Method study of subjectivity to ‘make the unseen seen’. First, a wide-ranging universe of subjective thoughts and feelings experienced during goal pursuit are explored.. These are generated from literature and a Qualtrics survey to create a Q-Set of 40 statements. Then 19 participants in professional and organisational settings offer their perspectives on these 40 Q-Set statements. Each rank them in a semi-forced distribution from ‘most like me’ to ‘least like me’ using Q-Sort software. From these individual perspectives, clusters of perspectives are identified using factor analysis and four distinct viewpoints, have emerged. Findings: These Goal Pursuit Viewpoints offer insight into the states and self-talk experienced by coachees and may not reflect the assumption of positive thinking associated with achieving goals. The four Viewpoints are 1) the Positive View, 2) the Realistic View 3) The Dreamer View and 4) The Conflicted View. With only a quarter of the Dreamer View, and a third of the Positive view going on to achieve their goals, these assumptions need review. And with all the Realistic View going on to achieve their goals, the role of self-doubt, overwhelm and anxiousness in goal achievement cannot be overlooked. Contribution: This study offers greater insight and understanding of people's inner experiences as they pursue goals and highlights the necessary and normal negative states associated with goal achievement. It also offers a practical tool of 40 ‘Clarity Card’ Q-set statements to help coaches and coachees explore the current state and help navigate the journey towards goal achievement. It calls into question whether goals should always be part of coaching, and if values, identity, and purpose may play a greater role than goals

Keywords: self-talk, mental health, inner critic, inner coach

Procedia PDF Downloads 63
5494 Tuberculosis and Associated Transient Hyperglycaemia in Peri-Urban South Africa: Implications for Diabetes Screening in High Tuberculosis/HIV Burden Settings

Authors: Mmamapudi Kubjane, Natacha Berkowitz, Rene Goliath, Naomi S. Levitt, Robert J. Wilkinson, Tolu Oni

Abstract:

Background: South Africa remains a high tuberculosis (TB) burden country globally and the burden of diabetes – a TB risk factor is growing rapidly. As an infectious disease, TB also induces transient hyperglycaemia. Therefore, screening for diabetes in newly diagnosed tuberculosis patients may result in misclassification of transient hyperglycaemia as diabetes. Objective: The objective of this study was to determine and compare the prevalence of hyperglycaemia (diabetes and impaired glucose regulation (IGR)) in TB patients and to assess the cross-sectional association between TB and hyperglycaemia at enrolment and after three months of follow-up. Methods: Consecutive adult TB and non-TB participants presenting at a TB clinic in Cape Town were enrolled in this cross-sectional study and follow-up between July 2013 and August 2015. Diabetes was defined as self-reported diabetes, fasting plasma glucose (FPG) ≥ 7.0 mmol·L⁻¹ or glycated haemoglobin (HbA1c) ≥ 6.5%. IGR was defined as FPG 5.5– < 7.0 mmol·L⁻¹ or HbA1c 5.7– < 6.5%. TB patients initiated treatment. After three months, all participants were followed up and screened for diabetes again. The association between TB and hyperglycaemia was assessed using logistic regression adjusting for potential confounders including sex, age, income, hypertension, waist circumference, previous prisoner, marital status, work status, HIV status. Results: Diabetes screening was performed in 852 participants (414 TB and 438 non-TB) at enrolment and in 639 (304 TB and 335 non-TB) at three-month follow-up. The prevalence of HIV-1 infection was 69.6% (95% confidence interval (CI), 64.9–73.8 %) among TB patients, and 58.2% (95% CI, 53.5–62.8 %) among the non-TB participants. Glycaemic levels were much higher in TB patients than in the non-TB participants but decreased over time. Among TB patients, the prevalence of IGR was 65.2% (95% CI 60.1 - 69.9) at enrollment and 21.5% (95% CI 17.2-26.5) at follow-up; and was 50% (45.1 - 54.94) and 32% (95% CI 27.9 - 38.0) respectively, among non-TB participants. The prevalence of diabetes in TB patients was 12.5% (95% CI 9.69 – 16.12%) at enrolment and 9.2% (95% CI, 6.43–13.03%) at follow-up; and was 10.04% (95% CI, 7.55–13.24%) and 8.06% (95% CI, 5.58–11.51) respectively, among non-TB participants. The association between TB and IGT was significant at enrolment (adjusted odds ratio (OR) 2.26 (95% CI, 1.55-3.31) but disappeared at follow-up 0.84 (0.53 - 1.36). However, the TB-diabetes association remained positive and significant both at enrolment (2.41 (95% CI, 1.3-4.34)) and follow-up (OR 3.31 (95% CI, 1.5 - 7.25)). Conclusion: Transient hyperglycaemia exists during tuberculosis. This has implications on diabetes screening in TB patients and suggests a need for diabetes confirmation tests during or after TB treatment. Nonetheless, the association between TB and diabetes noted at enrolment persists at 3 months highlighting the importance of diabetes control and prevention for TB control. Further research is required to investigate the impact of hyperglycaemia (transient or otherwise) on TB outcomes to ascertain the clinical significance of hyperglycemia at enrolment.

Keywords: diabetes, impaired glucose regulation, transient hyperglycaemia, tuberculosis

Procedia PDF Downloads 166
5493 Risk of Fatal and Non-Fatal Coronary Heart Disease and Stroke Events among Adult Patients with Hypertension: Basic Markov Model Inputs for Evaluating Cost-Effectiveness of Hypertension Treatment: Systematic Review of Cohort Studies

Authors: Mende Mensa Sorato, Majid Davari, Abbas Kebriaeezadeh, Nizal Sarrafzadegan, Tamiru Shibru, Behzad Fatemi

Abstract:

Markov model, like cardiovascular disease (CVD) policy model based simulation, is being used for evaluating the cost-effectiveness of hypertension treatment. Stroke, angina, myocardial infarction (MI), cardiac arrest, and all-cause mortality were included in this model. Hypertension is a risk factor for a number of vascular and cardiac complications and CVD outcomes. Objective: This systematic review was conducted to evaluate the comprehensiveness of this model across different regions globally. Methods: We searched articles written in the English language from PubMed/Medline, Ovid/Medline, Embase, Scopus, Web of Science, and Google scholar with a systematic search query. Results: Thirteen cohort studies involving a total of 2,165,770 (1,666,554 hypertensive adult population and 499,226 adults with treatment-resistant hypertension) were included in this scoping review. Hypertension is clearly associated with coronary heart disease (CHD) and stroke mortality, unstable angina, stable angina, MI, heart failure (HF), sudden cardiac death, transient ischemic attack, ischemic stroke, subarachnoid hemorrhage, intracranial hemorrhage, peripheral arterial disease (PAD), and abdominal aortic aneurism (AAA). Association between HF and hypertension is variable across regions. Treatment resistant hypertension is associated with a higher relative risk of developing major cardiovascular events and all-cause mortality when compared with non-resistant hypertension. However, it is not included in the previous CVD policy model. Conclusion: The CVD policy model used can be used in most regions for the evaluation of the cost-effectiveness of hypertension treatment. However, hypertension is highly associated with HF in Latin America, the Caribbean, Eastern Europe, and Sub-Saharan Africa. Therefore, it is important to consider HF in the CVD policy model for evaluating the cost-effectiveness of hypertension treatment in these regions. We do not suggest the inclusion of PAD and AAA in the CVD policy model for evaluating the cost-effectiveness of hypertension treatment due to a lack of sufficient evidence. Researchers should consider the effect of treatment-resistant hypertension either by including it in the basic model or during setting the model assumptions.

Keywords: cardiovascular disease policy model, cost-effectiveness analysis, hypertension, systematic review, twelve major cardiovascular events

Procedia PDF Downloads 76
5492 Maneuvering Modelling of a One-Degree-of-Freedom Articulated Vehicle: Modeling and Experimental Verification

Authors: Mauricio E. Cruz, Ilse Cervantes, Manuel J. Fabela

Abstract:

The evaluation of the maneuverability of road vehicles is generally carried out through the use of specialized computer programs due to the advantages they offer compared to the experimental method. These programs are based on purely geometric considerations of the characteristics of the vehicles, such as main dimensions, the location of the axles, and points of articulation, without considering parameters such as weight distribution and magnitude, tire properties, etc. In this paper, we address the problem of maneuverability in a semi-trailer truck to navigate urban streets, maneuvering yards, and parking lots, using the Ackerman principle to propose a kinematic model that, through geometric considerations, it is possible to determine the space necessary to maneuver safely. The model was experimentally validated by conducting maneuverability tests with an articulated vehicle. The measurements were made through a GPS that allows us to know the position, trajectory, and speed of the vehicle, an inertial motion unit (IMU) that allows measuring the accelerations and angular speeds in the semi-trailer, and an instrumented steering wheel that allows measuring the angle of rotation of the flywheel, the angular velocity and the torque applied to the flywheel. To obtain the steering angle of the tires, a parameterization of the complete travel of the steering wheel and its equivalent in the tires was carried out. For the tests, 3 different angles were selected, and 3 turns were made for each angle in both directions of rotation (left and right turn). The results showed that the proposed kinematic model achieved 95% accuracy for speeds below 5 km / h. The experiments revealed that that tighter maneuvers increased significantly the space required and that the vehicle maneuverability was limited by the size of the semi-trailer. The maneuverability was also tested as a function of the vehicle load and 3 different load levels we used: light, medium, and heavy. It was found that the internal turning radii also increased with the load, probably due to the changes in the tires' adhesion to the pavement since heavier loads had larger contact wheel-road surfaces. The load was found as an important factor affecting the precision of the model (up to 30%), and therefore I should be considered. The model obtained is expected to be used to improve maneuverability through a robust control system.

Keywords: articuled vehicle, experimental validation, kinematic model, maneuverability, semi-trailer truck

Procedia PDF Downloads 119
5491 Human Rabies Survivors in India: Epidemiological, Immunological and Virological Studies

Authors: Madhusudana S. N., Reeta Mani, Ashwini S. Satishchandra P., Netravati, Udhani V., Fiaz A., Karande S.

Abstract:

Rabies is an acute encephalitis which is considered 100% fatal despite occasional reports of survivors. However, in recent times more cases of human rabies survivors are being reported. In the last 5 years, there are six laboratories confirmed human rabies survivors in India alone. All cases were children below 15 years and all contracted the disease by dog bites. All of them also had received the full or partial course of rabies vaccination and 4 out of 6 had also received rabies immunoglobulin. All cases were treated in intensive care units in hospitals at Bangalore, Mumbai, Chandigarh, Lucknow and Goa. We report here the results of immunological and virological studies conducted at our laboratory on these patients. The clinical samples that were obtained from these patients were Serum, CSF, nuchal skin biopsy and saliva. Serum and CSF samples were subjected to standard RFFIT for estimation of rabies neutralizing antibodies. Skin biopsy, CSF and saliva were processed by TaqMan real-time PCR for detection of viral RNA. CSF, saliva and skin homogenates were also processed for virus isolation by inoculation of suckling mice. The PBMCs isolated from fresh blood was subjected to ELISPOT assay to determine the type of immune response (Th1/Th2). Both CSF and serum were also investigated for selected cytokines by Luminex assay. The level of antibodies to virus G protein and N protein were determined by ELISA. All survivors had very high titers of RVNA in serum and CSF 100 fold higher than non-survivors and vaccine controls. A five-fold rise in titer could be demonstrated in 4 out of 6 patients. All survivors had a significant increase in antibodies to G protein in both CSF and serum when compared to non-survivors. There was a profound and robust Th1 response in all survivors indicating that interferon gamma could play an important factor in virus clearance. We could isolate viral RNA in only one patient four years after he had developed symptoms. The partial N gene sequencing revealed 99% homology to species I strain prevalent in India. Levels of selected cytokines in CSF and serum did not reveal any difference between survivors and non-survivors. To conclude, survival from rabies is mediated by virus-specific immune responses of the host and clearance of rabies virus from CNS may involve the participation of both Th2 and Th1 immune responses.

Keywords: rabies, rabies treatment, rabies survivors, immune reponse in rabies encephalitis

Procedia PDF Downloads 333
5490 Designing for Wearable Interactions: Exploring Care Design for Design Anthropology and Participatory Design

Authors: Wei-Chen Chang, Yu-Cheng Pei

Abstract:

This research examines wearable interaction design to mediate the design anthropology and participatory design found in technology and fashion. We will discuss the principles of design anthropology and participatory design using a wearable and fashion product process to transmit the ‘people-situation-reason-object’ method and analyze five sense applied examples that provide new thinking for designers engaged in future industry. Design anthropology and Participatory Design attempt to engage physiological and psychological design through technology-function, meaning-form and fashion aesthetics to achieve cognition between user and environment. The wearable interaction provides technological characteristics and semantic ideas transmitted to craft-cultural, collective, cheerful and creative performance. It is more confident and innovative attempt, that is able to achieve a joyful, fundamental interface. This study takes two directions for cultural thinking as the basis to establish a set of life-craft designs with interactive experience objects by users that assist designers in examining the sensual feelings to initiate a new lifestyle value.

Keywords: design anthropology, wearable design, design communication, participatory design

Procedia PDF Downloads 240
5489 The Supply Chain Management and Supply Chain Responsiveness in the Competitiveness of the Agrofood Sector: An Econometric Analysis

Authors: Alma Lucero Ortiz, Mario Gómez

Abstract:

The purpose of this article is to conduct a theoretical and empirical study in order to analyze how the Supply Chain Management (SCM) and Supply Chain Responsiveness (SCR) affects the competitive advantage of the agrofood sector in 2017, in particular, the exporting companies of berries in Mexico. This work is presented in two parts, as a first part is developed a theoretical analysis of the main studies to measure the variables subject to the study. Subsequently an empirical study is carried out through field work and to process the data a logical econometric model is performed to be able to evaluate the effect of the SCM and SCR on the competitive advantage in the companies exporting berries. The results suggest that the SCM has a positive effect on the competitive advantage of the companies under study, so it is necessary to implement greater practices oriented towards a suitable SCM for the companies to achieve a competitive performance. In the case of SCR, it was found that this variable does not have effect on competitive advantage.

Keywords: competitive advantage, econometric model, supply chain management, supply chain responsiveness, sustained competitive advantage

Procedia PDF Downloads 244
5488 Local Texture and Global Color Descriptors for Content Based Image Retrieval

Authors: Tajinder Kaur, Anu Bala

Abstract:

An image retrieval system is a computer system for browsing, searching, and retrieving images from a large database of digital images a new algorithm meant for content-based image retrieval (CBIR) is presented in this paper. The proposed method combines the color and texture features which are extracted the global and local information of the image. The local texture feature is extracted by using local binary patterns (LBP), which are evaluated by taking into consideration of local difference between the center pixel and its neighbors. For the global color feature, the color histogram (CH) is used which is calculated by RGB (red, green, and blue) spaces separately. In this paper, the combination of color and texture features are proposed for content-based image retrieval. The performance of the proposed method is tested on Corel 1000 database which is the natural database. The results after being investigated show a significant improvement in terms of their evaluation measures as compared to LBP and CH.

Keywords: color, texture, feature extraction, local binary patterns, image retrieval

Procedia PDF Downloads 371
5487 Analyzing the Heat Transfer Mechanism in a Tube Bundle Air-PCM Heat Exchanger: An Empirical Study

Authors: Maria De Los Angeles Ortega, Denis Bruneau, Patrick Sebastian, Jean-Pierre Nadeau, Alain Sommier, Saed Raji

Abstract:

Phase change materials (PCM) present attractive features that made them a passive solution for thermal comfort assessment in buildings during summer time. They show a large storage capacity per volume unit in comparison with other structural materials like bricks or concrete. If their use is matched with the peak load periods, they can contribute to the reduction of the primary energy consumption related to cooling applications. Despite these promising characteristics, they present some drawbacks. Commercial PCMs, as paraffines, offer a low thermal conductivity affecting the overall performance of the system. In some cases, the material can be enhanced, adding other elements that improve the conductivity, but in general, a design of the unit that optimizes the thermal performance is sought. The material selection is the departing point during the designing stage, and it does not leave plenty of room for optimization. The PCM melting point depends highly on the atmospheric characteristics of the building location. The selection must relay within the maximum, and the minimum temperature reached during the day. The geometry of the PCM container and the geometrical distribution of these containers are designing parameters, as well. They significantly affect the heat transfer, and therefore its phenomena must be studied exhaustively. During its lifetime, an air-PCM unit in a building must cool down the place during daytime, while the melting of the PCM occurs. At night, the PCM must be regenerated to be ready for next uses. When the system is not in service, a minimal amount of thermal exchanges is desired. The aforementioned functions result in the presence of sensible and latent heat storage and release. Hence different types of mechanisms drive the heat transfer phenomena. An experimental test was designed to study the heat transfer phenomena occurring in a circular tube bundle air-PCM exchanger. An in-line arrangement was selected as the geometrical distribution of the containers. With the aim of visual identification, the containers material and a section of the test bench were transparent. Some instruments were placed on the bench for measuring temperature and velocity. The PCM properties were also available through differential scanning calorimeter (DSC) tests. An evolution of the temperature during both cycles, melting and solidification were obtained. The results showed some phenomena at a local level (tubes) and on an overall level (exchanger). Conduction and convection appeared as the main heat transfer mechanisms. From these results, two approaches to analyze the heat transfer were followed. The first approach described the phenomena in a single tube as a series of thermal resistances, where a pure conduction controlled heat transfer was assumed in the PCM. For the second approach, the temperature measurements were used to find some significant dimensionless numbers and parameters as Stefan, Fourier and Rayleigh numbers, and the melting fraction. These approaches allowed us to identify the heat transfer phenomena during both cycles. The presence of natural convection during melting might have been stated from the influence of the Rayleigh number on the correlations obtained.

Keywords: phase change materials, air-PCM exchangers, convection, conduction

Procedia PDF Downloads 182
5486 Generating Swarm Satellite Data Using Long Short-Term Memory and Generative Adversarial Networks for the Detection of Seismic Precursors

Authors: Yaxin Bi

Abstract:

Accurate prediction and understanding of the evolution mechanisms of earthquakes remain challenging in the fields of geology, geophysics, and seismology. This study leverages Long Short-Term Memory (LSTM) networks and Generative Adversarial Networks (GANs), a generative model tailored to time-series data, for generating synthetic time series data based on Swarm satellite data, which will be used for detecting seismic anomalies. LSTMs demonstrated commendable predictive performance in generating synthetic data across multiple countries. In contrast, the GAN models struggled to generate synthetic data, often producing non-informative values, although they were able to capture the data distribution of the time series. These findings highlight both the promise and challenges associated with applying deep learning techniques to generate synthetic data, underscoring the potential of deep learning in generating synthetic electromagnetic satellite data.

Keywords: LSTM, GAN, earthquake, synthetic data, generative AI, seismic precursors

Procedia PDF Downloads 38
5485 Rheological Properties of Thermoresponsive Poly(N-Vinylcaprolactam)-g-Collagen Hydrogel

Authors: Serap Durkut, A. Eser Elcin, Y. Murat Elcin

Abstract:

Stimuli-sensitive polymeric hydrogels have received extensive attention in the biomedical field due to their sensitivity to physical and chemical stimuli (temperature, pH, ionic strength, light, etc.). This study describes the rheological properties of a novel thermoresponsive poly(N-vinylcaprolactam)-g-collagen hydrogel. In the study, we first synthesized a facile and novel synthetic carboxyl group-terminated thermo-responsive poly(N-vinylcaprolactam)-COOH (PNVCL-COOH) via free radical polymerization. Further, this compound was effectively grafted with native collagen, by utilizing the covalent bond between the carboxylic acid groups at the end of the chains and amine groups of the collagen using cross-linking agent (EDC/NHS), forming PNVCL-g-Col. Newly-formed hybrid hydrogel displayed novel properties, such as increased mechanical strength and thermoresponsive characteristics. PNVCL-g-Col showed low critical solution temperature (LCST) at 38ºC, which is very close to the body temperature. Rheological studies determine structural–mechanical properties of the materials and serve as a valuable tool for characterizing. The rheological properties of hydrogels are described in terms of two dynamic mechanical properties: the elastic modulus G′ (also known as dynamic rigidity) representing the reversible stored energy of the system, and the viscous modulus G″, representing the irreversible energy loss. In order to characterize the PNVCL-g-Col, the rheological properties were measured in terms of the function of temperature and time during phase transition. Below the LCST, favorable interactions allowed the dissolution of the polymer in water via hydrogen bonding. At temperatures above the LCST, PNVCL molecules within PNVCL-g-Col aggregated due to dehydration, causing the hydrogel structure to become dense. When the temperature reached ~36ºC, both the G′ and G″ values crossed over. This indicates that PNVCL-g-Col underwent a sol-gel transition, forming an elastic network. Following temperature plateau at 38ºC, near human body temperature the sample displayed stable elastic network characteristics. The G′ and G″ values of the PNVCL-g-Col solutions sharply increased at 6-9 minute interval, due to rapid transformation into gel-like state and formation of elastic networks. Copolymerization with collagen leads to an increase in G′, as collagen structure contains a flexible polymer chain, which bestows its elastic properties. Elasticity of the proposed structure correlates with the number of intermolecular cross-links in the hydrogel network, increasing viscosity. However, at 8 minutes, G′ and G″ values sharply decreased for pure collagen solutions due to the decomposition of the elastic and viscose network. Complex viscosity is related to the mechanical performance and resistance opposing deformation of the hydrogel. Complex viscosity of PNVCL-g-Col hydrogel was drastically changed with temperature and the mechanical performance of PNVCL-g-Col hydrogel network increased, exhibiting lesser deformation. Rheological assessment of the novel thermo-responsive PNVCL-g-Col hydrogel, exhibited that the network has stronger mechanical properties due to both permanent stable covalent bonds and physical interactions, such as hydrogen- and hydrophobic bonds depending on temperature.

Keywords: poly(N-vinylcaprolactam)-g-collagen, thermoresponsive polymer, rheology, elastic modulus, stimuli-sensitive

Procedia PDF Downloads 245
5484 Multi-Spectral Medical Images Enhancement Using a Weber’s law

Authors: Muna F. Al-Sammaraie

Abstract:

The aim of this research is to present a multi spectral image enhancement methods used to achieve highly real digital image populates only a small portion of the available range of digital values. Also, a quantitative measure of image enhancement is presented. This measure is related with concepts of the Webers Low of the human visual system. For decades, several image enhancement techniques have been proposed. Although most techniques require profuse amount of advance and critical steps, the result for the perceive image are not as satisfied. This study involves changing the original values so that more of the available range is used; then increases the contrast between features and their backgrounds. It consists of reading the binary image on the basis of pixels taking them byte-wise and displaying it, calculating the statistics of an image, automatically enhancing the color of the image based on statistics calculation using algorithms and working with RGB color bands. Finally, the enhanced image is displayed along with image histogram. A number of experimental results illustrated the performance of these algorithms. Particularly the quantitative measure has helped to select optimal processing parameters: the best parameters and transform.

Keywords: image enhancement, multi-spectral, RGB, histogram

Procedia PDF Downloads 332
5483 Lifetime Assessment for Test Strips of POCT Device through Accelerated Degradation Test

Authors: Jinyoung Choi, Sunmook Lee

Abstract:

In general, single parameter, i.e. temperature, as an accelerating parameter is used to assess the accelerated stability of Point-of-Care Testing (POCT) diagnostic devices. However, humidity also plays an important role in deteriorating the strip performance since major components of test strips are proteins such as enzymes. 4 different Temp./Humi. Conditions were used to assess the lifetime of strips. Degradation of test strips were studied through the accelerated stability test and the lifetime was assessed using commercial POCT products. The life distribution of strips, which were obtained by monitoring the failure time of test strip under each stress condition, revealed that the weibull distribution was the most proper distribution describing the life distribution of strips used in the present study. Equal shape parameters were calculated to be 0.9395 and 0.9132 for low and high concentrations, respectively. The lifetime prediction was made by adopting Peck Eq. Model for Stress-Life relationship, and the B10 life was calculated to be 70.09 and 46.65 hrs for low and high concentrations, respectively.

Keywords: accelerated degradation, diagnostic device, lifetime assessment, POCT

Procedia PDF Downloads 419
5482 Beyond Classic Program Evaluation and Review Technique: A Generalized Model for Subjective Distributions with Flexible Variance

Authors: Byung Cheol Kim

Abstract:

The Program Evaluation and Review Technique (PERT) is widely used for project management, but it struggles with subjective distributions, particularly due to its assumptions of constant variance and light tails. To overcome these limitations, we propose the Generalized PERT (G-PERT) model, which enhances PERT by incorporating variability in three-point subjective estimates. Our methodology extends the original PERT model to cover the full range of unimodal beta distributions, enabling the model to handle thick-tailed distributions and offering formulas for computing mean and variance. This maintains the simplicity of PERT while providing a more accurate depiction of uncertainty. Our empirical analysis demonstrates that the G-PERT model significantly improves performance, particularly when dealing with heavy-tail subjective distributions. In comparative assessments with alternative models such as triangular and lognormal distributions, G-PERT shows superior accuracy and flexibility. These results suggest that G-PERT offers a more robust solution for project estimation while still retaining the user-friendliness of the classic PERT approach.

Keywords: PERT, subjective distribution, project management, flexible variance

Procedia PDF Downloads 24
5481 Spatial-Temporal Awareness Approach for Extensive Re-Identification

Authors: Tyng-Rong Roan, Fuji Foo, Wenwey Hseush

Abstract:

Recent development of AI and edge computing plays a critical role to capture meaningful events such as detection of an unattended bag. One of the core problems is re-identification across multiple CCTVs. Immediately following the detection of a meaningful event is to track and trace the objects related to the event. In an extensive environment, the challenge becomes severe when the number of CCTVs increases substantially, imposing difficulties in achieving high accuracy while maintaining real-time performance. The algorithm that re-identifies cross-boundary objects for extensive tracking is referred to Extensive Re-Identification, which emphasizes the issues related to the complexity behind a great number of CCTVs. The Spatial-Temporal Awareness approach challenges the conventional thinking and concept of operations which is labor intensive and time consuming. The ability to perform Extensive Re-Identification through a multi-sensory network provides the next-level insights – creating value beyond traditional risk management.

Keywords: long-short-term memory, re-identification, security critical application, spatial-temporal awareness

Procedia PDF Downloads 117
5480 The Different Improvement of Numerical Magnitude and Spatial Representation of Numbers to Symbolic Approximate Arithmetic: A Training Study of Preschooler

Authors: Yu Liang, Wei Wei

Abstract:

Spatial representation of numbers and numerical magnitude are important for preschoolers’ mathematical ability. Mental number line, a typical index to measure numbers spatial representation, and numerical comparison are both related to arithmetic obviously. However, they seem to rely on different mechanisms and probably influence arithmetic through different mechanisms. In line with this idea, preschool children were trained with two tasks to investigate which one is more important for approximate arithmetic. The training of numerical processing and number line estimation were proved to be effective. They both improved the ability of approximate arithmetic. When the difficulty of approximate arithmetic was taken into account, the performance in number line training group was not significantly different among three levels. However, two harder levels achieved significance in numerical comparison training group. Thus, comparing spatial representation ability, symbolic approximation arithmetic relies more on numerical magnitude. Educational implications of the study were discussed.

Keywords: approximate arithmetic, mental number line, numerical magnitude, preschooler

Procedia PDF Downloads 258
5479 Communicative Language Teaching Technique: A Neglected Approach in Reading Comprehension Instruction

Authors: Olumide Yusuf Jimoh

Abstract:

Reading comprehension is an interactive and purposeful process of getting meaning from and bringing meaning to a text. Over the years, teachers of the English Language (in Nigeria) have been glued to the monotonous method of making students read comprehension passages silently and then answer the questions that follow such passages without making the reading session interactive. Hence, students often find such exercises monotonous and boring. Consequently, students'’ interest in language learning continues to dwindle, and this often affects their overall academic performance. Relying on Communicative Accommodation Theory therefore, the study employed the qualitative research design method to x-ray Communicative Language Teaching Approach (CLTA) in reading comprehension. Moreover, techniques such as the Genuinely Collaborative Reading Approach (GCRA), Jigsaw reading, Pre-reading, and Post-reading tasks were examined. The researcher submitted that effective reading comprehension could not be done passively. Students must respond to what they read; they must interact not only with the materials being read but also with one another and with the teacher; this can be achieved by developing communicative and interactive reading programs.

Keywords: collaborative reading approach, communicative teaching, interactive reading program, pre-reading task, reading comprehension

Procedia PDF Downloads 113
5478 Research on Knowledge Graph Inference Technology Based on Proximal Policy Optimization

Authors: Yihao Kuang, Bowen Ding

Abstract:

With the increasing scale and complexity of knowledge graph, modern knowledge graph contains more and more types of entity, relationship, and attribute information. Therefore, in recent years, it has been a trend for knowledge graph inference to use reinforcement learning to deal with large-scale, incomplete, and noisy knowledge graphs and improve the inference effect and interpretability. The Proximal Policy Optimization (PPO) algorithm utilizes a near-end strategy optimization approach. This allows for more extensive updates of policy parameters while constraining the update extent to maintain training stability. This characteristic enables PPOs to converge to improved strategies more rapidly, often demonstrating enhanced performance early in the training process. Furthermore, PPO has the advantage of offline learning, effectively utilizing historical experience data for training and enhancing sample utilization. This means that even with limited resources, PPOs can efficiently train for reinforcement learning tasks. Based on these characteristics, this paper aims to obtain a better and more efficient inference effect by introducing PPO into knowledge inference technology.

Keywords: reinforcement learning, PPO, knowledge inference

Procedia PDF Downloads 248
5477 Neural Network Based Approach of Software Maintenance Prediction for Laboratory Information System

Authors: Vuk M. Popovic, Dunja D. Popovic

Abstract:

Software maintenance phase is started once a software project has been developed and delivered. After that, any modification to it corresponds to maintenance. Software maintenance involves modifications to keep a software project usable in a changed or a changing environment, to correct discovered faults, and modifications, and to improve performance or maintainability. Software maintenance and management of software maintenance are recognized as two most important and most expensive processes in a life of a software product. This research is basing the prediction of maintenance, on risks and time evaluation, and using them as data sets for working with neural networks. The aim of this paper is to provide support to project maintenance managers. They will be able to pass the issues planned for the next software-service-patch to the experts, for risk and working time evaluation, and afterward to put all data to neural networks in order to get software maintenance prediction. This process will lead to the more accurate prediction of the working hours needed for the software-service-patch, which will eventually lead to better planning of budget for the software maintenance projects.

Keywords: laboratory information system, maintenance engineering, neural networks, software maintenance, software maintenance costs

Procedia PDF Downloads 364
5476 A 5G Architecture Based to Dynamic Vehicular Clustering Enhancing VoD Services Over Vehicular Ad hoc Networks

Authors: Lamaa Sellami, Bechir Alaya

Abstract:

Nowadays, video-on-demand (VoD) applications are becoming one of the tendencies driving vehicular network users. In this paper, considering the unpredictable vehicle density, the unexpected acceleration or deceleration of the different cars included in the vehicular traffic load, and the limited radio range of the employed communication scheme, we introduce the “Dynamic Vehicular Clustering” (DVC) algorithm as a new scheme for video streaming systems over VANET. The proposed algorithm takes advantage of the concept of small cells and the introduction of wireless backhauls, inspired by the different features and the performance of the Long Term Evolution (LTE)- Advanced network. The proposed clustering algorithm considers multiple characteristics such as the vehicle’s position and acceleration to reduce latency and packet loss. Therefore, each cluster is counted as a small cell containing vehicular nodes and an access point that is elected regarding some particular specifications.

Keywords: video-on-demand, vehicular ad-hoc network, mobility, vehicular traffic load, small cell, wireless backhaul, LTE-advanced, latency, packet loss

Procedia PDF Downloads 145
5475 Copper Selenide Nanobelts: An Electrocatalyst for Methanol Electro-Oxidation Reaction

Authors: Nabi Ullah

Abstract:

The energy crisis of the current society has attracted research attention for alternative energy sources. Methanol oxidation is the source of energy but needs efficient electrocatalysts like Pt. However, their practical ability is hindered due to cost and poisoning effects. In this regard, an efficient catalyst is required for methanol oxidation. Herein, high temperature, pressure, and diethylenetryamine (DETA) as reaction medium/structure directing agent during the solvothermal method are used for nanobelt Cu₃Se₂/Cu₁.₈Se (mostly hexagonal appearance) formation. The electrocatalyst shows optimized methanol electrooxidation reaction (MOR) response in 1 M KOH and 0.5 M methanol at a scan rate of 50 mV/s and delivers a current density of 7.12 mA/mg at a potential of 0.65 V (vs Ag/AgCl). The catalyst exhibits high electrochemical active surface area (ECSA) (0.088 mF/cm²) and low Rct with good stability for 3600 s, which favors its high MOR performance. This high response is due to its 2D hexagonal nanobelt morphology, which provides a large surface area for reaction. The space among nanobelts reduces diffusion kinetics, and the rough/irregular edge increases the reaction site to improve the methanol oxidation reaction overall.

Keywords: energy application, electrocatalysis, MOR, nanobelt

Procedia PDF Downloads 72
5474 The Impact of the Business Process Reengineering on the Practices of the Human Resources Management in the Franco Tunisian Company-Network

Authors: Nesrine Bougarech, Habib Affes

Abstract:

This research lays the emphasis on the business process reengineering (BPR) which consists in radically altering the organizational processes through the optimal use of information technology (IT) to attain major enhancements in terms of quality, performance and productivity. A survey of the business process reengineering (BPR) was carried out in three French groups and their subsidiaries in Tunisia. The data collected were qualitatively analyzed in an attempt to test the main indicators of the success of a business process reengineering project (BPR) and to compare the importance of these indicators in the context of France versus Tunisia. The study corroborates that the respect of the inherent principles of the business process reengineering (BPR) and the diversity of the human resources involved in the project can lead to better productivity, higher quality of the goods or services and lower cost. Additionally, our results mirror the extent to which the respect of the principles and the diversity of resources are more important in the French companies than in their Tunisian subsidiaries.

Keywords: business process reengineering (BPR), human resources management (HRM), information technology (IT), management

Procedia PDF Downloads 411
5473 Comparison of Spiral Circular Coil and Helical Coil Structures for Wireless Power Transfer System

Authors: Zhang Kehan, Du Luona

Abstract:

Wireless power transfer (WPT) systems have been widely investigated for advantages of convenience and safety compared to traditional plug-in charging systems. The research contents include impedance matching, circuit topology, transfer distance et al. for improving the efficiency of WPT system, which is a decisive factor in the practical application. What is more, coil structures such as spiral circular coil and helical coil with variable distance between two turns also have indispensable effects on the efficiency of WPT systems. This paper compares the efficiency of WPT systems utilizing spiral or helical coil with variable distance between two turns, and experimental results show that efficiency of spiral circular coil with an optimum distance between two turns is the highest. According to efficiency formula of resonant WPT system with series-series topology, we introduce M²/R₋₁ to measure the efficiency of spiral circular coil and helical coil WPT system. If the distance between two turns s is too close, proximity effect theory shows that the induced current in the conductor, caused by a variable flux created by the current flows in the skin of vicinity conductor, is the opposite direction of source current and has assignable impart on coil resistance. Thus in two coil structures, s affects coil resistance. At the same time, when the distance between primary and secondary coils is not variable, s can also make the influence on M to some degrees. The aforementioned study proves that s plays an indispensable role in changing M²/R₋₁ and then can be adjusted to find the optimum value with which WPT system achieves the highest efficiency. In actual application situations of WPT systems especially in underwater vehicles, miniaturization is one vital issue in designing WPT system structures. Limited by system size, the largest external radius of spiral circular coil is 100 mm, and the largest height of helical coil is 40 mm. In other words, the turn of coil N changes with s. In spiral circular and helical structures, the distance between each two turns in secondary coil is set as a constant value 1 mm to guarantee that the R2 is not variable. Based on the analysis above, we set up spiral circular coil and helical coil model using COMSOL to analyze the value of M²/R₋₁ when the distance between each two turns in primary coil sp varies from 0 mm to 10 mm. In the two structure models, the distance between primary and secondary coils is 50 mm and wire diameter is chosen as 1.5 mm. The turn of coil in secondary coil are 27 in helical coil model and 20 in spiral circular coil model. The best value of s in helical coil structure and spiral circular coil structure are 1 mm and 2 mm respectively, in which the value of M²/R₋₁ is the largest. It is obviously to select spiral circular coil as the first choice to design the WPT system for that the value of M²/R₋₁ in spiral circular coil is larger than that in helical coil under the same condition.

Keywords: distance between two turns, helical coil, spiral circular coil, wireless power transfer

Procedia PDF Downloads 352
5472 End-to-End Control and Management of Multi-AS Virtual Service Networks Using SDN and Autonomic Computing Architecture

Authors: Yong Xue, Daniel A. Menascé

Abstract:

Automated and end-to-end network resource management and provisioning for virtual service networks in a multiple autonomous systems (a.k.a multi-AS) environment is a challenging and open problem. This paper proposes a novel, scalable and interoperable high-level architecture that incorporates a number of emerging enabling technologies including Software Defined Network (SDN), Network Function Virtualization (NFV), Service Oriented Architecture (SOA), and Autonomic Computing. The proposed architecture can be used to not only automate network resource management and provisioning for virtual service networks across multiple autonomous substrate networks, but also provide an adaptive capability for achieving optimal network resource management and maintaining network-level end-to-end network performance as well. The paper argues that this SDN and autonomic computing based architecture lays a solid foundation that can facilitate the development of the future Internet based on the pluralistic paradigm.

Keywords: virtual network, software defined network, virtual service network, adaptive resource management, SOA, multi-AS, inter-domain

Procedia PDF Downloads 536
5471 Quality of Today's Teachers: Post-Certified Teachers' Competence in Alleviating Poverties towards a Sustainable Development

Authors: Sudirman

Abstract:

Competence is a term describing capability that correlates with a person’s occupation. The competence of a teacher consists of four, i.e., pedagogical, professional, personality and social competence. These four components are implemented during interacting with students to motivate the students and improve their achievement. The objective of this qualitative study is to explore the roles and contributions of certified teachers in alleviating the issue of poverty to promote a sustainable development. The data comprise primary and secondary data which were generated from observation, interview, documentation and library research. Furthermore, this study offers in-depth information regarding the performance of the teachers in coping with poverty and sustaining development. The result shows that the teacher’s competence positively contributes to the improvement of students’ achievement. This helps the students to prepare for the real work experience by which it results in a better income and, therefore, alleviate poverty. All in all, the quality of today’s teachers can be measured by their contribution in enhancing the students’ competence prior to entering real work, resulting in a wealthy society. This is to deal with poverty and conceptualizing a sustainable development.

Keywords: competence, development, poverty, teachers

Procedia PDF Downloads 154