Search results for: hybrid work
14570 Towards Developing a Self-Explanatory Scheduling System Based on a Hybrid Approach
Authors: Jian Zheng, Yoshiyasu Takahashi, Yuichi Kobayashi, Tatsuhiro Sato
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In the study, we present a conceptual framework for developing a scheduling system that can generate self-explanatory and easy-understanding schedules. To this end, a user interface is conceived to help planners record factors that are considered crucial in scheduling, as well as internal and external sources relating to such factors. A hybrid approach combining machine learning and constraint programming is developed to generate schedules and the corresponding factors, and accordingly display them on the user interface. Effects of the proposed system on scheduling are discussed, and it is expected that scheduling efficiency and system understandability will be improved, compared with previous scheduling systems.Keywords: constraint programming, factors considered in scheduling, machine learning, scheduling system
Procedia PDF Downloads 32414569 Hybrid Energy System for the German Mining Industry: An Optimized Model
Authors: Kateryna Zharan, Jan C. Bongaerts
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In recent years, economic attractiveness of renewable energy (RE) for the mining industry, especially for off-grid mines, and a negative environmental impact of fossil energy are stimulating to use RE for mining needs. Being that remote area mines have higher energy expenses than mines connected to a grid, integration of RE may give a mine economic benefits. Regarding the literature review, there is a lack of business models for adopting of RE at mine. The main aim of this paper is to develop an optimized model of RE integration into the German mining industry (GMI). Hereby, the GMI with amount of around 800 mill. t. annually extracted resources is included in the list of the 15 major mining country in the world. Accordingly, the mining potential of Germany is evaluated in this paper as a perspective market for RE implementation. The GMI has been classified in order to find out the location of resources, quantity and types of the mines, amount of extracted resources, and access of the mines to the energy resources. Additionally, weather conditions have been analyzed in order to figure out where wind and solar generation technologies can be integrated into a mine with the highest efficiency. Despite the fact that the electricity demand of the GMI is almost completely covered by a grid connection, the hybrid energy system (HES) based on a mix of RE and fossil energy is developed due to show environmental and economic benefits. The HES for the GMI consolidates a combination of wind turbine, solar PV, battery and diesel generation. The model has been calculated using the HOMER software. Furthermore, the demonstrated HES contains a forecasting model that predicts solar and wind generation in advance. The main result from the HES such as CO2 emission reduction is estimated in order to make the mining processing more environmental friendly.Keywords: diesel generation, German mining industry, hybrid energy system, hybrid optimization model for electric renewables, optimized model, renewable energy
Procedia PDF Downloads 34414568 Secure Transfer of Medical Images Using Hybrid Encryption Authentication, Confidentiality, Integrity
Authors: Boukhatem Mohammed Belkaid, Lahdir Mourad
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In this paper, we propose a new encryption system for security issues medical images. The hybrid encryption scheme is based on AES and RSA algorithms to validate the three security services are authentication, integrity, and confidentiality. Privacy is ensured by AES, authenticity is ensured by the RSA algorithm. Integrity is assured by the basic function of the correlation between adjacent pixels. Our system generates a unique password every new session of encryption, that will be used to encrypt each frame of the medical image basis to strengthen and ensure his safety. Several metrics have been used for various tests of our analysis. For the integrity test, we noticed the efficiencies of our system and how the imprint cryptographic changes at reception if a change affects the image in the transmission channel.Keywords: AES, RSA, integrity, confidentiality, authentication, medical images, encryption, decryption, key, correlation
Procedia PDF Downloads 54014567 A Decision Support System to Detect the Lumbar Disc Disease on the Basis of Clinical MRI
Authors: Yavuz Unal, Kemal Polat, H. Erdinc Kocer
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In this study, a decision support system comprising three stages has been proposed to detect the disc abnormalities of the lumbar region. In the first stage named the feature extraction, T2-weighted sagittal and axial Magnetic Resonance Images (MRI) were taken from 55 people and then 27 appearance and shape features were acquired from both sagittal and transverse images. In the second stage named the feature weighting process, k-means clustering based feature weighting (KMCBFW) proposed by Gunes et al. Finally, in the third stage named the classification process, the classifier algorithms including multi-layer perceptron (MLP- neural network), support vector machine (SVM), Naïve Bayes, and decision tree have been used to classify whether the subject has lumbar disc or not. In order to test the performance of the proposed method, the classification accuracy (%), sensitivity, specificity, precision, recall, f-measure, kappa value, and computation times have been used. The best hybrid model is the combination of k-means clustering based feature weighting and decision tree in the detecting of lumbar disc disease based on both sagittal and axial MR images.Keywords: lumbar disc abnormality, lumbar MRI, lumbar spine, hybrid models, hybrid features, k-means clustering based feature weighting
Procedia PDF Downloads 52014566 Hybrid Localization Schemes for Wireless Sensor Networks
Authors: Fatima Babar, Majid I. Khan, Malik Najmus Saqib, Muhammad Tahir
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This article provides range based improvements over a well-known single-hop range free localization scheme, Approximate Point in Triangulation (APIT) by proposing an energy efficient Barycentric coordinate based Point-In-Triangulation (PIT) test along with PIT based trilateration. These improvements result in energy efficiency, reduced localization error and improved localization coverage compared to APIT and its variants. Moreover, we propose to embed Received signal strength indication (RSSI) based distance estimation in DV-Hop which is a multi-hop localization scheme. The proposed localization algorithm achieves energy efficiency and reduced localization error compared to DV-Hop and its available improvements. Furthermore, a hybrid multi-hop localization scheme is also proposed that utilize Barycentric coordinate based PIT test and both range based (Received signal strength indicator) and range free (hop count) techniques for distance estimation. Our experimental results provide evidence that proposed hybrid multi-hop localization scheme results in two to five times reduction in the localization error compare to DV-Hop and its variants, at reduced energy requirements.Keywords: Localization, Trilateration, Triangulation, Wireless Sensor Networks
Procedia PDF Downloads 46914565 Useful Characteristics of Pleurotus Mushroom Hybrids
Authors: Suvalux Chaichuchote, Ratchadaporn Thonghem
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Pleurotus mushroom is one of popular edible mushrooms in Thailand. It is much favored by consumers due to its delicious taste and high nutrition. It is commonly used as an ingredient in several dishes. The commercially cultivated strain grown in most farms is the Pleurotus sp., Hed Bhutan, that is widely distributed to mushroom farms throughout the country and can be cultivated almost all year round. However, it demands different cultivated strains from mushroom growers, therefore, the improving mushroom strains should be done to their benefits. In this study, we used a di-mon mating method to hybrid production from Hed Bhutan (P-3) as dikaryon material and monokaryotic mycelium were isolated from basidiospores of other three Pleurotus sp. by single spore isolation. The 3 hybrids: P-3XSA-6, P-3XSB-24 and P-3XSE-5 were recognized from the 12 hybridized successfully. They were appropriate hybridized in terms of fruiting body performance in the three time cycles of cultivation such as the number of days until growing, time for pinning, color and shape of fruiting bodies and yield. For genetic study, genomic DNAs of both Hed Bhutan (P-3) and three hybrids were extracted. A couple of primer ITS1 and ITS4 were used to amplify the gene coding for ITS1, ITS2 and 5.8S rRNA. The similarities between these amplified genes and databases of DNA revealed that Hed Bhutan (P-3) was the Pleurotus pulmonarius as well as P-3XSA-6, P-3XSB-24 and P-3XSE-5 hybrids. Furthermore, Hed Bhutan (P3) and three hybrids were distributed to 3 small-scale farms, with mushroom farming experience, in the countryside. To address this, one hundred and twenty mushroom bags of each strain were supplied to them. The findings, by interview, indicated two mushroom farmers were satisfied with P-3XSA-6 hybrid and P-3XSB-24 hybrid, thanks to their simultaneous fruiting time and good yield. While the other was satisfied with P-3XSB-24 hybrid due to its good yield and P-3XSE-5 hybrids thanks to its gradually fruiting body, benefiting in frequent harvest. Overall, farmers adopted all hybrids to grow as commercially cultivated strains as well as Hed Bhutan (P-3) strain.Keywords: dikaryon, monokaryon, pleurotus, strain improvement
Procedia PDF Downloads 25414564 Review of Factors Which Affect Throttling by Oxidiser Flow Control in Hybrid Rocket Engine
Authors: Natcha Laethongkham, Gayan Ramanayake, Philip Charlesworth, Leshan Uggalla
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The throttling process in hybrid rocket engines (HREs) poses challenges due to inherent instability, impacting the engine’s reliability and robustness. Identifying and advancing existing technology is crucial to meet the demands of complex mission profiles required for next-generation launch vehicles. This paper reviews the current literature, focusing on oxidiser flow control for throttling purposes in HREs. Covered areas include oxidiser choices, commonly used throttle valves, and literature trends. Common oxidisers for throttling are hydrogen peroxide, nitrous oxide, and liquid oxygen. Two frequently chosen valves for throttling are the ball and variation pintle valves. The review identifies two primary research focuses: flow control valve studies and control system design. The current research stage is highlighted, and suggestions for future directions are proposed to advance thrust control systems in HREs. This includes further studies in existing research focuses and exploring new approaches such as system scheme design, numerical modelling, and applications.Keywords: hybrid rocket engines, oxidiser flow control, thrust control, throttle valve, review
Procedia PDF Downloads 2614563 Mechanism of Action of New Sustainable Flame Retardant Additives in Polyamide 6,6
Authors: I. Belyamani, M. K. Hassan, J. U. Otaigbe, W. R. Fielding, K. A. Mauritz, J. S. Wiggins, W. L. Jarrett
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We have investigated the flame-retardant efficiency of special new phosphate glass (P-glass) compositions having different glass transition temperatures (Tg) on the processing conditions of polyamide 6,6 (PA6,6) and the final hybrid flame retardancy (FR). We have showed that the low Tg P glass composition (i.e., ILT 1) is a promising flame retardant for PA6,6 at a concentration of up to 15 wt. % compared to intermediate (IIT 3) and high (IHT 1) Tg P glasses. Cone calorimetry data showed that the ILT 1 decreased both the peak heat release rate and the total heat amount released from the PA6,6/ILT 1 hybrids, resulting in an efficient formation of a glassy char layer. These intriguing findings prompted to address several questions concerning the mechanism of action of the different P glasses studied. The general mechanism of action of phosphorous based FR additives occurs during the combustion stage by enhancing the morphology of the char and the thermal shielding effect. However, the present work shows that P glass based FR additives act during melt processing of PA6,6/P glass hybrids. Dynamic mechanical analysis (DMA) revealed that the Tg of PA6,6/ILT 1 was significantly shifted to a lower Tg (~65 oC) and another transition appeared at high temperature (~ 166 oC), thus indicating a strong interaction between PA6,6 and ILT 1. This was supported by a drop in the melting point and crystallinity of the PA6,6/ILT 1 hybrid material as detected by differential scanning calorimetry (DSC). The dielectric spectroscopic investigation of the networks’ molecular level structural variations (i.e. hybrids chain motion, Tg and sub-Tg relaxations) agreed very well with the DMA and DSC findings; it was found that the three different P glass compositions did not show any effect on the PA6,6 sub-Tg relaxations (related to the NH2 and OH chain end groups motions). Nevertheless, contrary to IIT 3 and IHT 1 based hybrids, the PA6,6/ILT 1 hybrid material showed an evidence of splitting the PA6,6 Tg relaxations into two peaks. Finally, the CPMAS 31P-NMR data confirmed the miscibility between ILT 1 and PA6,6 at the molecular level, as a much larger enhancement in cross-polarization for the PA6,6/15%ILT 1 hybrids was observed. It can be concluded that compounding low Tg P-glass (i.e. ILT 1) with PA6,6 facilitates hydrolytic chain scission of the PA6,6 macromolecules through a potential chemical interaction between phosphate and the alpha-Carbon of the amide bonds of the PA6,6, leading to better flame retardant properties.Keywords: broadband dielectric spectroscopy, composites, flame retardant, polyamide, phosphate glass, sustainable
Procedia PDF Downloads 23814562 Fuzzy Time Series Forecasting Based on Fuzzy Logical Relationships, PSO Technique, and Automatic Clustering Algorithm
Authors: A. K. M. Kamrul Islam, Abdelhamid Bouchachia, Suang Cang, Hongnian Yu
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Forecasting model has a great impact in terms of prediction and continues to do so into the future. Although many forecasting models have been studied in recent years, most researchers focus on different forecasting methods based on fuzzy time series to solve forecasting problems. The forecasted models accuracy fully depends on the two terms that are the length of the interval in the universe of discourse and the content of the forecast rules. Moreover, a hybrid forecasting method can be an effective and efficient way to improve forecasts rather than an individual forecasting model. There are different hybrids forecasting models which combined fuzzy time series with evolutionary algorithms, but the performances are not quite satisfactory. In this paper, we proposed a hybrid forecasting model which deals with the first order as well as high order fuzzy time series and particle swarm optimization to improve the forecasted accuracy. The proposed method used the historical enrollments of the University of Alabama as dataset in the forecasting process. Firstly, we considered an automatic clustering algorithm to calculate the appropriate interval for the historical enrollments. Then particle swarm optimization and fuzzy time series are combined that shows better forecasting accuracy than other existing forecasting models.Keywords: fuzzy time series (fts), particle swarm optimization, clustering algorithm, hybrid forecasting model
Procedia PDF Downloads 25014561 Effect of Social Media on Knowledge Work
Authors: Pekka Makkonen, Georgios Lampropoulos, Kerstin Siakas
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This paper examines the impact of social media on knowledge work. It discloses and highlights which specific aspects, areas and tasks of knowledge work can be improved by the use of social media. Moreover, the study includes a survey about higher education students’ viewpoints in regard to the use of social media as a means to enhance knowledge work and knowledge sharing. The analysis has been conducted based both on empirical data and on discussions about the sources dealing with knowledge work and how it can be enhanced by using social media. The results show that social media can improve knowledge work, knowledge building and maintenance tasks in which communication, information sharing and collaboration play a vital role. Additionally, by using social media, personal, collaborative and supplementary work activities can be enhanced. Based on the results of the study, we suggest how knowledge work can be enhanced when using the contemporary information and communications technologies (ICTs) of the 21st century and recommend future directions towards improving knowledge work.Keywords: knowledge work, social media, social media services, improving work performance
Procedia PDF Downloads 16114560 Who Am I at Work: Work Identity Formation
Authors: Carol Belle-Hallsworth
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Human interaction at work evolves over time and, with it, work identity. The social identity is built upon the development of its underpinning and preceding stages. Work identity can be viewed in the same way and will shift based on changes in the work environment and challenges to the work identity (threats to the four stages). This paper provides an analysis of how the stages of trust, autonomy, industry and initiative are related to the employee identity at work. Describing how they are related to each other and the development of identity. It has become common to notice changes in employee behavior during and after major operational changes in an organization. Previous studies suggest that there are emotional triggers that result in the new behaviors displayed. This study seeks to test a theoretical model by testing the relationship between the first four Erikson stages as constructs. A randomized sample of participants undertook a self-administered survey to capture information on trust, autonomy, initiative, and industry.Keywords: work identity, change management, organizational management, technology implementation
Procedia PDF Downloads 30614559 Reinforcing Effects of Natural Micro-Particles on the Dynamic Impact Behaviour of Hybrid Bio-Composites Made of Short Kevlar Fibers Reinforced Thermoplastic Composite Armor
Authors: Edison E. Haro, Akindele G. Odeshi, Jerzy A. Szpunar
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Hybrid bio-composites are developed for use in protective armor through positive hybridization offered by reinforcement of high-density polyethylene (HDPE) with Kevlar short fibers and palm wood micro-fillers. The manufacturing process involved a combination of extrusion and compression molding techniques. The mechanical behavior of Kevlar fiber reinforced HDPE with and without palm wood filler additions are compared. The effect of the weight fraction of the added palm wood micro-fillers is also determined. The Young modulus was found to increase as the weight fraction of organic micro-particles increased. However, the flexural strength decreased with increasing weight fraction of added micro-fillers. The interfacial interactions between the components were investigated using scanning electron microscopy. The influence of the size, random alignment and distribution of the natural micro-particles was evaluated. Ballistic impact and dynamic shock loading tests were performed to determine the optimum proportion of Kevlar short fibers and organic micro-fillers needed to improve impact strength of the HDPE. These results indicate a positive hybridization by deposition of organic micro-fillers on the surface of short Kevlar fibers used in reinforcing the thermoplastic matrix leading to enhancement of the mechanical strength and dynamic impact behavior of these materials. Therefore, these hybrid bio-composites can be promising materials for different applications against high velocity impacts.Keywords: hybrid bio-composites, organic nano-fillers, dynamic shocking loading, ballistic impacts, energy absorption
Procedia PDF Downloads 11314558 History, Challenges and Solutions for Social Work Education and Recognition in Vietnam
Authors: Thuy Bui Anh, Ngan Nguyen Thi Thanh
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Currently, social work in Vietnam is entering the first step in the development process to become a true profession with a strong position in society. However, Spirit of helping and sharing of social work has already existed in the daily life of Vietnamese people for a very long time, becoming a precious heritage passed down from ancestors to the next generations while expanding the territory, building and defending for the country. Following the stream of history, charity work in Vietnam has gradually transformed itself towards a more professional work, especially in the last 2 decades. Accordingly, more than 50 universities and educational institutions in Vietnam have been licensed to train social work, ensuring a stronger foundation on human resources working in this field. Despite the strong growth, social work profession, social work education and the recognition of the role of the social workers still need to be fueled to develop, responded to the increasing demand of Vietnam society.Keywords: education, history, recognition, social work, Vietnam
Procedia PDF Downloads 32014557 Stability of Hybrid Systems
Authors: Kreangkri Ratchagit
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This paper is concerned with exponential stability of switched linear systems with interval time-varying delays. The time delay is any continuous function belonging to a given interval, in which the lower bound of delay is not restricted to zero. By constructing a suitable augmented Lyapunov-Krasovskii functional combined with Leibniz-Newton’s formula, a switching rule for the exponential stability of switched linear systems with interval time-varying delays and new delay-dependent sufficient conditions for the exponential stability of the systems are first established in terms of LMIs. Finally, some examples are exploited to illustrate the effectiveness of the proposed schemes.Keywords: exponential stability, hybrid systems, timevarying delays, Lyapunov-Krasovskii functional, Leibniz-Newton’s formula
Procedia PDF Downloads 45814556 Effectiveness of an Unorthodox Intervention for Work-Family Interaction: A Field Experiment
Authors: Hassan Rasool
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There is limited research in the intervention domain of work family interaction. We identified that meditation could be effective in coping work family conflict and nurturing work family facilitation across domains. We conducted pretest posttest control group field experiment on a sample of sixty employees to test the effectiveness of meditation in a financial sector organization. Empirical evidence confirms that the intervention was effective in coping work family conflict & nurturing facilitation across work & home domains. The intervention, also positively affected a known outcome (i.e. satisfaction at work and home) of work family interaction. Future research perspectives on the use of unorthodox interventions in the domain of work family interaction are also discussed.Keywords: work family interaction, meditation, satisfaction, experiment
Procedia PDF Downloads 45814555 Hybrid Laser-Gas Metal Arc Welding of ASTM A106-B Steel Pipes
Authors: Masoud Mohammadpour, Nima Yazdian, Radovan Kovacevic
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The Oil and Gas industries are vigorously looking for new ways to increase the efficiency of their pipeline constructions. Besides the other approaches, implementing of new welding methods for joining pipes can be the best candidate on this regard. Hybrid Laser Arc Welding (HLAW) with the capabilities of high welding speed, deep penetration, and excellent gap bridging ability can be a possible alternative method in pipeline girth welding. This paper investigates the feasibility of applying the HLAW to join ASTM A106-B as the mostly used piping material for transporting high-temperature and high-pressure fluids and gases. The experiments were carried out on six-inch diameter pipes with the wall thickness of 10mm. AWS ER 70 S6 filler wire with diameter of 1.2mm was employed. Relating to this welding procedure, characterization of welded samples such as hardness, tensile testing and Charpy V-notch testing were performed and the results will be reported in this paper. In order to have better understanding about the thermal history and the microstructural alterations caused by the welding heat cycle, a comprehensive Finite Element (FE) model was also conducted. The obtained results have shown that the Gas Metal Arc Welding (GMAW) procedure with the minimum number of 5 passes to complete the wall thickness, was reduced to only single pass by using the HLAW process with the welding time less than 15s.Keywords: finite element modeling, high-temperature service, hybrid laser/arc welding, welding pipes
Procedia PDF Downloads 20814554 Performance Evaluation of Karanja Oil Based Biodiesel Engine Using Modified Genetic Algorithm
Authors: G. Bhushan, S. Dhingra, K. K. Dubey
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This paper presents the evaluation of performance (BSFC and BTE), combustion (Pmax) and emission (CO, NOx, HC and smoke opacity) parameters of karanja biodiesel in a single cylinder, four stroke, direct injection diesel engine by considering significant engine input parameters (blending ratio, compression ratio and load torque). Multi-objective optimization of performance, combustion and emission parameters is also carried out in a karanja biodiesel engine using hybrid RSM-NSGA-II technique. The pareto optimum solutions are predicted by running the hybrid RSM-NSGA-II technique. Each pareto optimal solution is having its own importance. Confirmation tests are also conducted at randomly selected few pareto solutions to check the authenticity of the results.Keywords: genetic algorithm, rsm, biodiesel, karanja
Procedia PDF Downloads 30614553 Comparative Analysis of Feature Extraction and Classification Techniques
Authors: R. L. Ujjwal, Abhishek Jain
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In the field of computer vision, most facial variations such as identity, expression, emotions and gender have been extensively studied. Automatic age estimation has been rarely explored. With age progression of a human, the features of the face changes. This paper is providing a new comparable study of different type of algorithm to feature extraction [Hybrid features using HAAR cascade & HOG features] & classification [KNN & SVM] training dataset. By using these algorithms we are trying to find out one of the best classification algorithms. Same thing we have done on the feature selection part, we extract the feature by using HAAR cascade and HOG. This work will be done in context of age group classification model.Keywords: computer vision, age group, face detection
Procedia PDF Downloads 36814552 Hybrid System Configurations and Charging Strategies for Isolated Electric Tuk-Tuk Charging Station in South Africa
Authors: L. Bokopane, K. Kusakana, H. J. Vermaark
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The success of renewable powered electric vehicle charging station in isolated areas depends highly on the availability and sustainability of renewable resources all year round at a selected location. The main focus of this paper is to discuss the possible charging strategies that could be implemented to find the best possible configuration of an electric Tuk-Tuk charging station at a given location within South Africa. The charging station is designed, modeled and simulated to evaluate its performances. The techno-economic analysis of different feasible supply configurations of the charging station using renewable energies is simulated using HOMER software and the results compared in order to select the best possible charging strategies in terms of cost of energy consumed.Keywords: electric tuk-tuk, renewable energy, energy Storage, hybrid systems, HOMER
Procedia PDF Downloads 51314551 Pultrusion of Side by Side Glass/Polypropylene Fibers: Study of Flexural and Shear Properties
Authors: Behrooz Ataee, Mohammad Golzar
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The main purpose of using side by side (SBS) hybrid yarn in pultrusion thermoplastic method is reprisal the effect of high viscosity in melted thermoplastic and reduction of distance between reinforced fiber and melted thermoplastic. SBS hybrid fiber yarn composed of thermoplastic fibers and fiber reinforcement should be produced in the preparation of pultruded thermoplastic composites prepreg to reach better impregnation. An experimental set-up was designed and built to pultrude continues polypropylene and glass fiber to get obtain a suitable impregnated round prepregs. In final stage, the round prepregs come together to produce rectangular profile. Higher fiber volume fraction produces higher void volume fraction, however the second stage of the production process of rectangular profile and the cold die decrease 50% of the void volume fraction. Results show that whit increasing void volume fraction, flexural and shear strength decrease. Also, under certain conditions of parameters the pultruded profiles exhibit better flexural and shear strength. The pulling speed seems to have the greatest influence on the profile quality. In addition, adding cold die strongly increases the surface quality of rectangular profile.Keywords: thermoplastic pultrusion, hybrid pultrusion, side-by-side fibers, impregnation
Procedia PDF Downloads 25814550 A Hybrid Particle Swarm Optimization-Nelder- Mead Algorithm (PSO-NM) for Nelson-Siegel- Svensson Calibration
Authors: Sofia Ayouche, Rachid Ellaia, Rajae Aboulaich
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Today, insurers may use the yield curve as an indicator evaluation of the profit or the performance of their portfolios; therefore, they modeled it by one class of model that has the ability to fit and forecast the future term structure of interest rates. This class of model is the Nelson-Siegel-Svensson model. Unfortunately, many authors have reported a lot of difficulties when they want to calibrate the model because the optimization problem is not convex and has multiple local optima. In this context, we implement a hybrid Particle Swarm optimization and Nelder Mead algorithm in order to minimize by least squares method, the difference between the zero-coupon curve and the NSS curve.Keywords: optimization, zero-coupon curve, Nelson-Siegel-Svensson, particle swarm optimization, Nelder-Mead algorithm
Procedia PDF Downloads 43014549 Model Updating Based on Modal Parameters Using Hybrid Pattern Search Technique
Authors: N. Guo, C. Xu, Z. C. Yang
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In order to ensure the high reliability of an aircraft, the accurate structural dynamics analysis has become an indispensable part in the design of an aircraft structure. Therefore, the structural finite element model which can be used to accurately calculate the structural dynamics and their transfer relations is the prerequisite in structural dynamic design. A dynamic finite element model updating method is presented to correct the uncertain parameters of the finite element model of a structure using measured modal parameters. The coordinate modal assurance criterion is used to evaluate the correlation level at each coordinate over the experimental and the analytical mode shapes. Then, the weighted summation of the natural frequency residual and the coordinate modal assurance criterion residual is used as the objective function. Moreover, the hybrid pattern search (HPS) optimization technique, which synthesizes the advantages of pattern search (PS) optimization technique and genetic algorithm (GA), is introduced to solve the dynamic FE model updating problem. A numerical simulation and a model updating experiment for GARTEUR aircraft model are performed to validate the feasibility and effectiveness of the present dynamic model updating method, respectively. The updated results show that the proposed method can be successfully used to modify the incorrect parameters with good robustness.Keywords: model updating, modal parameter, coordinate modal assurance criterion, hybrid genetic/pattern search
Procedia PDF Downloads 16114548 Conflating Voluntary Sex Work and Trafficked Sex Work in Malaysia
Authors: Haezreena Begum Abdul Hamid
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This article will explore the conflation between voluntary sex work and trafficked sex work. In doing so, the article will analyse the meaning of trafficking according to the United Nations ‘Protocol to Prevent, Suppress and Punish Trafficking in Persons, Especially Women and Children’ and the Malaysian Anti-Trafficking in Persons and Anti-Migrant Smuggling Act, 2007 (ATIP), and discuss the ambiguities that may arise in understanding the term. While the law on human trafficking has long been understood by scholars, key stakeholders, and enforcement officers, identifying a victim of trafficking is far from being straight forward. This is because of the diverse understanding on sex trafficking and sex work, and the fact that ‘consent’ by trafficked persons remains irrelevant in cases of trafficking. As a result, women who voluntarily engage in sex work are sometimes categorised as ‘trafficked’ and are ‘rescued’ by the authorities in the name of ‘protection’, while those who insist of having agency can be charged for violating the immigration laws. In light of such circumstances, this article aims to explore the conflation between voluntary sex work and trafficked sex work and how such conflation have succeeded in fostering distrust between sex workers and authorities.Keywords: voluntary sex work, trafficked sex work, sex work, coercion, protection
Procedia PDF Downloads 24214547 A Novel Design Methodology for a 1.5 KW DC/DC Converter in EV and Hybrid EV Applications
Authors: Farhan Beg
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This paper presents a method for the efficient implementation of a unidirectional or bidirectional DC/DC converter. The DC/DC converter is used essentially for energy exchange between the low voltage service battery and a high voltage battery commonly found in Electric Vehicle applications. In these applications, apart from cost, efficiency of design is an important characteristic. A useful way to reduce the size of electronic equipment in the electric vehicles is proposed in this paper. The technique simplifies the mechanical complexity and maximizes the energy usage using the latest converter control techniques. Moreover a bidirectional battery charger for hybrid electric vehicles is also implemented in this paper. Several simulations on the test system have been carried out in Matlab/Simulink environment. The results exemplify the robustness of the proposed design methodology in case of a 1.5 KW DC-DC converter.Keywords: DC-DC converters, electric vehicles, power electronics, direct current control
Procedia PDF Downloads 72714546 An Equitable Strategy to Amend Zero-Emission Vehicles Incentives for Travelers: A Policy Review
Authors: Marie Louis
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Even though many stakeholders are doing their very best to promote public transportation around the world, many areas are still public transportation non-accessible. With travelers purchasing and driving their private vehicles can be considered as a threat to all three aspects of the sustainability (e.g., economical, social, environmental). However, most studies that considered simultaneously all three aspects of the sustainability concept when planning and designing public transportation for a corridor have found tradeoffs among the said three aspects.One of the tradeoffs was identified by looking at tipping points of the travel demands to question whether transit agencies/and or transportation policymakers should either operate smaller buses or provide incentives to purchase Leadership in Energy and Environmental Design (LEED)-Qualified low-emission vehicles or greener vehicles (e.g., hybrid). However, how and when do the department of environmental protection (DEP) and the department of revenue (DOR) figure out how much incentives to give to each traveler who lives in a zoning that is considered as public transportation inaccessible or accessible? To answer this policy question, this study aims to compare the greenhouse gases (GHGs) emissions when hybrid and conventional cars are used to access public transportation stops/stations. Additionally, this study also intends to review previous states that have already adopted low-emissions vehicle (LEVs) or Zero-Emissions Vehicles (ZEVs) to diminish the daily GHGs pollutants.Keywords: LEED-qualified vehicles, public transit accessibility, hybrid vehicles incentives, sustainability trade-offs
Procedia PDF Downloads 19514545 Impact of Work and Family Conflict on Employee Self Esteem
Authors: Romana P. Khokhar
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The purpose of this study was to explore the impact of work-family conflict on self-esteem. On the basis of the literature reviewed, it was hypothesized that 1) work-family conflict has an impact on self- esteem, 2). There would be a gender difference on the variable of work family conflict. Data for this study was taken from a sample of 70 employees within the banking industry since this industry is generally associated with higher levels of work-family conflict. Statistical tests performed were regression and t-test. Self-esteem was assessed with the 10-item Rosenberg Self-Esteem Scale (RSE; Rosenberg, 1965) and Work-Family Conflict Scale (WFCS; Netemeyer, R. G., Boles, J. S., & McMurrian, R. 1996) was used to assess the level of work –family conflict. The results indicated that an increase in work-family conflict resulted in lower self-esteem due to the various pressures evidenced in a complicated network of direct and indirect influences. It was also determined that there is less effect of work-family conflict on the female workers, as opposed to the male population, leading to the conclusion that in the case of the female workers the impact on self-esteem was not significant.Keywords: work and family conflict, self-esteem, employee
Procedia PDF Downloads 49914544 Simulations of a Jet Impinging on a Flat Plate
Authors: Reda Mankbadi
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In this paper we explore the use of a second-order unstructured-grid, finite-volume code for direct noise prediction. We consider a Mach 1.5 jet impinging on a perpendicular flat plate. Hybrid LES-RANS simulations are used to calculate directly both the flow field and the radiated sound. The ANSYS Fluent commercial code is utilized for the calculations. The acoustic field is obtained directly from the simulations and is compared with the integral approach of Ffowcs Williams-Hawkings (FWH). Results indicate the existence of a preferred radiation angle. The spectrum obtained is in good agreement with observations. This points out to the possibility of handling the effects of complicated geometries on noise radiation by using unstructured second-orders codes.Keywords: CFD, Ffowcs Williams-Hawkings (FWH), imping jet, ANSYS fluent commercial code, hybrid LES-RANS simulations
Procedia PDF Downloads 45314543 Thermo-Ecological Assessment of a Hybrid Solar Greenhouse Dryer for Grape Drying
Authors: Ilham Ihoume, Rachid Tadili, Nora Arbaoui
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The use of solar energy in agricultural applications has gained significant attention in recent years as a sustainable and environmentally friendly alternative to conventional energy sources. In particular, solar drying of crops has been identified as an effective method to preserve agricultural produce while minimizing energy consumption and reducing carbon emissions. In this context, the present study aims to evaluate the thermo-economic and ecological performance of a solar-electric hybrid greenhouse dryer designed for grape drying. The proposed system integrates solar collectors, an electric heater, and a greenhouse structure to create a controlled and energy-efficient environment for grape drying. The thermo-economic assessment involves the analysis of the thermal performance, energy consumption, and cost-effectiveness of the solar-electric hybrid greenhouse dryer. On the other hand, the ecological assessment focuses on the environmental impact of the system in terms of carbon emissions and sustainability. The findings of this study are expected to contribute to the development of sustainable agricultural practices and the promotion of renewable energy technologies in the context of food production. Moreover, the results may serve as a basis for the design and optimization of similar solar drying systems for other crops and regions.Keywords: solar energy, sustainability, agriculture, energy analysis
Procedia PDF Downloads 6214542 Nanoparticles-Protein Hybrid-Based Magnetic Liposome
Authors: Amlan Kumar Das, Avinash Marwal, Vikram Pareek
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Liposome plays an important role in medical and pharmaceutical science as e.g. nano scale drug carriers. Liposomes are vesicles of varying size consisting of a spherical lipid bilayer and an aqueous inner compartment. Magnet-driven liposome used for the targeted delivery of drugs to organs and tissues1. These liposome preparations contain encapsulated drug components and finely dispersed magnetic particles. Liposomes are vesicles of varying size consisting of a spherical lipid bilayer and an aqueous inner compartment that are generated in vitro. These are useful in terms of biocompatibility, biodegradability, and low toxicity, and can control biodistribution by changing the size, lipid composition, and physical characteristics2. Furthermore, liposomes can entrap both hydrophobic and hydrophilic drugs and are able to continuously release the entrapped substrate, thus being useful drug carriers. Magnetic liposomes (MLs) are phospholipid vesicles that encapsulate magneticor paramagnetic nanoparticles. They are applied as contrast agents for magnetic resonance imaging (MRI)3. The biological synthesis of nanoparticles using plant extracts plays an important role in the field of nanotechnology4. Green-synthesized magnetite nanoparticles-protein hybrid has been produced by treating Iron (III)/Iron(II) chloride with the leaf extract of Dhatura Inoxia. The phytochemicals present in the leaf extracts act as a reducing as well stabilizing agents preventing agglomeration, which include flavonoids, phenolic compounds, cardiac glycosides, proteins and sugars. The magnetite nanoparticles-protein hybrid has been trapped inside the aqueous core of the liposome prepared by reversed phase evaporation (REV) method using oleic and linoleic acid which has been shown to be driven under magnetic field confirming the formation magnetic liposome (ML). Chemical characterization of stealth magnetic liposome has been performed by breaking the liposome and release of magnetic nanoparticles. The presence iron has been confirmed by colour complex formation with KSCN and UV-Vis study using spectrophotometer Cary 60, Agilent. This magnet driven liposome using nanoparticles-protein hybrid can be a smart vesicles for the targeted drug delivery.Keywords: nanoparticles-protein hybrid, magnetic liposome, medical, pharmaceutical science
Procedia PDF Downloads 24814541 Solving Process Planning, Weighted Earliest Due Date Scheduling and Weighted Due Date Assignment Using Simulated Annealing and Evolutionary Strategies
Authors: Halil Ibrahim Demir, Abdullah Hulusi Kokcam, Fuat Simsir, Özer Uygun
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Traditionally, three important manufacturing functions which are process planning, scheduling and due-date assignment are performed sequentially and separately. Although there are numerous works on the integration of process planning and scheduling and plenty of works focusing on scheduling with due date assignment, there are only a few works on integrated process planning, scheduling and due-date assignment. Although due-dates are determined without taking into account of weights of the customers in the literature, here weighted due-date assignment is employed to get better performance. Jobs are scheduled according to weighted earliest due date dispatching rule and due dates are determined according to some popular due date assignment methods by taking into account of the weights of each job. Simulated Annealing, Evolutionary Strategies, Random Search, hybrid of Random Search and Simulated Annealing, and hybrid of Random Search and Evolutionary Strategies, are applied as solution techniques. Three important manufacturing functions are integrated step-by-step and higher integration levels are found better. Search meta-heuristics are found to be very useful while improving performance measure.Keywords: process planning, weighted scheduling, weighted due-date assignment, simulated annealing, evolutionary strategies, hybrid searches
Procedia PDF Downloads 462