Search results for: post-harvest loss
1499 Ferulic Acid-Grafted Chitosan: Thermal Stability and Feasibility as an Antioxidant for Active Biodegradable Packaging Film
Authors: Sarekha Woranuch, Rangrong Yoksan
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Active packaging has been developed based on the incorporation of certain additives, in particular antimicrobial and antioxidant agents, into packaging systems to maintain or extend product quality and shelf-life. Ferulic acid is one of the most effective natural phenolic antioxidants, which has been used in food, pharmaceutical and active packaging film applications. However, most phenolic compounds are sensitive to oxygen, light and heat; its activities are thus lost during product formulation and processing. Grafting ferulic acid onto polymer is an alternative to reduce its loss under thermal processes. Therefore, the objectives of the present research were to study the thermal stability of ferulic acid after grafting onto chitosan, and to investigate the possibility of using ferulic acid-grafted chitosan (FA-g-CTS) as an antioxidant for active biodegradable packaging film. FA-g-CTS was incorporated into biodegradable film via a two-step process, i.e. compounding extrusion at temperature up to 150 °C followed by blown film extrusion at temperature up to 175 °C. Although incorporating FA-g-CTS with a content of 0.02–0.16% (w/w) caused decreased water vapor barrier property and reduced extensibility, the films showed improved oxygen barrier property and antioxidant activity. Radical scavenging activity and reducing power of the film containing FA-g-CTS with a content of 0.04% (w/w) were higher than that of the naked film about 254% and 94%, respectively. Tensile strength and rigidity of the films were not significantly affected by adding FA-g-CTS with a content of 0.02–0.08% (w/w). The results indicated that FA-g-CTS could be potentially used as an antioxidant for active packaging film.Keywords: active packaging film, antioxidant activity, chitosan, ferulic acid
Procedia PDF Downloads 5031498 Improve Heat Pipe Thermal Performance in H-VAC Systems Using CFD Modeling
Authors: H. Shokouhmand, A. Ghanami
Abstract:
A heat pipe is simple heat transfer device which combines the conduction and phase change phenomena to control the heat transfer without any need for external power source. At a hot surface of the heat pipe, the liquid phase absorbs heat and changes to the vapor phase. The vapor phase flows to condenser region and with the loss of heat changes to the liquid phase. Due to gravitational force the liquid phase flows to the evaporator section. In HVAC systems, the working fluid is chosen based on the operating temperature. The heat pipe has significant capability to reduce the humidity in HVAC systems. Each HVAC system which uses the heater, humidifier, or dryer is a suitable nominate for the utilization of heat pipes. Generally, heat pipes have three main sections: condenser, adiabatic region, and evaporator. Performance investigation and optimization of heat pipes operation in order to increase their efficiency is crucial. In the present article, a parametric study is performed to improve the heat pipe performance. Therefore, the heat capacity of the heat pipe with respect to geometrical and confining parameters is investigated. For the better observation of heat pipe operation in HVAC systems, a CFD simulation in Eulerian-Eulerian multiphase approach is also performed. The results show that heat pipe heat transfer capacity is higher for water as working fluid with the operating temperature of 340 K. It is also showed that the vertical orientation of heat pipe enhances its heat transfer capacity.Keywords: heat pipe, HVAC system, grooved heat pipe, heat pipe limits
Procedia PDF Downloads 4361497 Noise Reduction in Web Data: A Learning Approach Based on Dynamic User Interests
Authors: Julius Onyancha, Valentina Plekhanova
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One of the significant issues facing web users is the amount of noise in web data which hinders the process of finding useful information in relation to their dynamic interests. Current research works consider noise as any data that does not form part of the main web page and propose noise web data reduction tools which mainly focus on eliminating noise in relation to the content and layout of web data. This paper argues that not all data that form part of the main web page is of a user interest and not all noise data is actually noise to a given user. Therefore, learning of noise web data allocated to the user requests ensures not only reduction of noisiness level in a web user profile, but also a decrease in the loss of useful information hence improves the quality of a web user profile. Noise Web Data Learning (NWDL) tool/algorithm capable of learning noise web data in web user profile is proposed. The proposed work considers elimination of noise data in relation to dynamic user interest. In order to validate the performance of the proposed work, an experimental design setup is presented. The results obtained are compared with the current algorithms applied in noise web data reduction process. The experimental results show that the proposed work considers the dynamic change of user interest prior to elimination of noise data. The proposed work contributes towards improving the quality of a web user profile by reducing the amount of useful information eliminated as noise.Keywords: web log data, web user profile, user interest, noise web data learning, machine learning
Procedia PDF Downloads 2651496 Hyaluronic Acid Binding to Link Domain of Stabilin-2 Receptor
Authors: Aleksandra Twarda, Dobrosława Krzemień, Grzegorz Dubin, Tad A. Holak
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Stabilin-2 belongs to the group of scavenger receptors and plays a crucial role in clearance of more than 10 ligands from the bloodstream, including hyaluronic acid, products of degradation of extracellular matrix and metabolic products. The Link domain, a defining feature of stabilin-2, has a sequence similar to Link domains in other hyaluronic acid receptors, such as CD44 or TSG-6, and is responsible for most of ligands binding. Present knowledge of signal transduction by stabilin-2, as well as ligands’ recognition and binding mechanism, is limited. Until now, no experimental structures have been solved for any segments of stabilin-2. It has recently been demonstrated that the stabilin-2 knock-out or blocking of the receptor by an antibody effectively opposes cancer metastasis by elevating the level of circulating hyaluronic acid. Moreover, loss of expression of stabilin-2 in a peri-tumourous liver correlates with increased survival. Solving of the crystal structure of stabilin-2 and elucidation of the binding mechanism of hyaluronic acid could enable the precise characterization of the interactions in the binding site. These results may allow for designing specific small-molecule inhibitors of stabilin-2 that could be used in cancer therapy. To carry out screening for crystallization of stabilin-2, we cloned constructs of the Link domain of various lengths with or without surrounding domains. The folding properties of the constructs were checked by nuclear magnetic resonance (NMR). It is planned to show the binding of hyaluronic acid to the Link domain using several biochemical methods, i.a. NMR, isothermal titration calorimetry and fluorescence polarization assay.Keywords: stabilin-2, Link domain, X-ray crystallography, NMR, hyaluronic acid, cancer
Procedia PDF Downloads 4031495 Adherence of Trauma and Orthopaedics Surgery Operative Notes to the RCS Good Surgical Practice Guidelines in Ashford and St. Peter's Hospital
Authors: Maryam Risla Shahul Hameed, Tharsiga Yogarajah, Fritzy Mathew, Tayyaba Syed, Shalin Shaunak
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Aim: Auditing the adherence of Trauma and Orthopaedics Operative notes to the RCS Good Surgical Practice Guidelines. Method: Clinical audit conducted on 150 operative notes over a period of 2 months April- May 2023, including emergency and elective surgeries performed in Ashford and St. Peter’s Hospital. The RCS Good Practice Surgical Guidelines for an ideal operative note were used to compare.Results: Date of the procedure and signature of the surgeon were mentioned in all the notes by default in the electronic template being used. Title of the operation performed and whether elective or emergency were mentioned by 92% and 45%, respectively. Name of theatre anaesthetist and operating surgeons were mentioned by 73% and 93% respectively. Time of surgery mentioned by 26%. Operative findings and operative diagnosis mentioned by 83% and 53% respectively. Incision and complications of surgery mentioned in 80% and 53%, respectively. Details of tissue added/ altered/ removed mentioned by 46%. Information on prosthesis or implant used is mentioned by 54%. Details of closure and anticipated blood loss mentioned in 91% and 45% respectively. Antibiotic prophylaxis was mentioned by 63%, out of which only 23% mentioned the name and duration of the antibiotic. VTE prophylaxis was mentioned by 84%, out of which only 23% and 29% mentioned the name and duration of the prophylaxis, respectively. Conclusion: There is more for improvement in the operative notes for better continuity of care between the operating surgeons and other doctors in the wards taking care of the patients post operatively. We recommend to follow a standardized guidelines by all the nationwide and a standard template to be followed by all.Keywords: surgery, notes, RCS, guidelines
Procedia PDF Downloads 1651494 Modelling and Optimization of Geothermal Energy in the Gulf of Suez
Authors: Amira Abdelhafez, Rufus Brunt
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Geothermal energy in Egypt represents a significant untapped renewable resource that can reduce reliance on conventional power generation. Exploiting these geothermal resources depends on depth, temperature range, and geological characteristics. The intracontinental rift setting of the Gulf of Suez (GoS)-Red Sea rift is a favourable tectonic setting for convection-dominated geothermal plays. The geothermal gradient across the GoS ranges from 24.9 to 86.66 °C/km, with a heat flow of 31-127.2 mW/m². Surface expressions of convective heat loss emerge along the gulf flanks as hot springs (e.g., Hammam Faraun) accompanying deeper geothermal resources. These thermal anomalies are driven mainly by the local tectonic configuration. Characterizing the structural framework of major faults and their control on reservoir properties and subsurface hydrothermal fluid circulation is vital for geothermal applications in the gulf. The geothermal play systems of the GoS depend on structural and lithological properties that contribute to heat storage and vertical transport. Potential geothermal reservoirs include the Nubia sandstones, which, due to their thickness, continuity, and contact with hot basement rocks at a mean depth of 3 km, create an extensive reservoir for geothermal fluids. To develop these geothermal resources for energy production, defining the permeability anisotropy of the reservoir due to faults and facies variation is a crucial step in our study, particularly the evaluation of influence on thermal breakthrough and production rates.Keywords: geothermal, October field, site specific study, reservoir modelling
Procedia PDF Downloads 111493 Optimization of Multistage Extractor for the Butanol Separation from Aqueous Solution Using Ionic Liquids
Authors: Dharamashi Rabari, Anand Patel
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n-Butanol can be regarded as a potential biofuel. Being resistive to corrosion and having high calorific value, butanol is a very attractive energy source as opposed to ethanol. By fermentation process called ABE (acetone, butanol, ethanol), bio-butanol can be produced. ABE carried out mostly by bacteria Clostridium acetobutylicum. The major drawback of the process is the butanol concentration higher than 10 g/L, delays the growth of microbes resulting in a low yield. It indicates the simultaneous separation of butanol from the fermentation broth. Two hydrophobic Ionic Liquids (ILs) 1-butyl-1-methylpiperidinium bis (trifluoromethylsulfonyl)imide [bmPIP][Tf₂N] and 1-hexyl-3-methylimidazolium bis (trifluoromethylsulfonyl)imide [hmim][Tf₂N] were chosen. The binary interaction parameters for both ternary systems i.e. [bmPIP][Tf₂N] + water + n-butanol and [hmim][Tf₂N] + water +n-butanol were taken from the literature that was generated by NRTL model. Particle swarm optimization (PSO) with the isothermal sum rate (ISR) method was used to optimize the cost of liquid-liquid extractor. For [hmim][Tf₂N] + water +n-butanol system, PSO shows 84% success rate with the number of stages equal to eight and solvent flow rate equal to 461 kmol/hr. The number of stages was three with 269.95 kmol/hr solvent flow rate for [bmPIP][Tf₂N] + water + n-butanol system. Moreover, both ILs were very efficient as the loss of ILs in raffinate phase was negligible.Keywords: particle swarm optimization, isothermal sum rate method, success rate, extraction
Procedia PDF Downloads 1221492 Estimation of Time Loss and Costs of Traffic Congestion: The Contingent Valuation Method
Authors: Amira Mabrouk, Chokri Abdennadher
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The reduction of road congestion which is inherent to the use of vehicles is an obvious priority to public authority. Therefore, assessing the willingness to pay of an individual in order to save trip-time is akin to estimating the change in price which was the result of setting up a new transport policy to increase the networks fluidity and improving the level of social welfare. This study holds an innovative perspective. In fact, it initiates an economic calculation that has the objective of giving an estimation of the monetized time value during the trips made in Sfax. This research is founded on a double-objective approach. The aim of this study is to i) give an estimation of the monetized value of time; an hour dedicated to trips, ii) determine whether or not the consumer considers the environmental variables to be significant, iii) analyze the impact of applying a public management of the congestion via imposing taxation of city tolls on urban dwellers. This article is built upon a rich field survey led in the city of Sfax. With the use of the contingent valuation method, we analyze the “declared time preferences” of 450 drivers during rush hours. Based on the fond consideration of attributed bias of the applied method, we bring to light the delicacy of this approach with regards to the revelation mode and the interrogative techniques by following the NOAA panel recommendations bearing the exception of the valorization point and other similar studies about the estimation of transportation externality.Keywords: willingness to pay, contingent valuation, time value, city toll
Procedia PDF Downloads 4341491 Co-Immobilization of Palladium Nanoparticles and Polyoxometalate into the Cavities of the Mesocellular Foams: A Biomimetic Cooperative Catalytic System for Aerobic Oxidation of Alcohols under Green Conditions
Authors: Saeed Chehri, Sirvan Moradi, Amin Rostami
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Cooperative catalyst systems have been developed as highly promising sustainable alternatives to traditional catalysts. In these catalysts, two or more catalytic centers cooperate to reduce the energy of chemical transformations. In nature, such systems are abundantly seen in metalloenzymes that use metal and an organic cofactor. We have designed a reusable cooperative catalyst oxidation system consisting of palladium nanoparticles and polyoxometalate. This biomimetic cooperative catalytic system was synthesized by the stepwise immobilization of palladium nanoparticlesandpolyoxometalateinto the same cavity of siliceous mesocellularfoams (Pd-POM@MCF)and wascharacterizedby SEM, EDX, FT-IR, TGAand ICP techniques. POM-Pd@MCF/HQexhibits high activity toward aerobic oxidation of alcohols to the corresponding carbonyl compoundsin water solvent at room temperature. The major novelties and advantages of this oxidation method are as follows: (i) this is the first report of the co-immobilization of polyoxometalateand palladium for use as a robust and highlyefficient heterogeneouscooperative oxidative nanocatalyst system for aerobic oxidation of alcohols, (ii) oxidation of alcoholswere performed using an ideal oxidant with good to high yields in a green solvent at ambient temperature and (iii) the immobilization of the oxygen-activating catalyst(polyoxometalate) and oxidizing catalyst (Pd) onto MCF provide practical cooperative catalyst the system that can be reused several times without a significant loss of activity (vi) the methodsconform to several of the guiding principles of green chemistry.Keywords: palladium nanoparticles, polyoxometalate, reusable cooperative catalytic system, biomimetic oxidation reaction
Procedia PDF Downloads 1181490 Historiography of Wood Construction in Portugal
Authors: João Gago dos Santos, Paulo Pereira Almeida
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The present study intends to deepen and understand the reasons that led to the decline and disappearance of wooden construction systems in Portugal, for that reason, its use in history must be analyzed. It is observed that this material was an integral part of the construction systems in Europe and Portugal for centuries, and it is possible to conclude that its decline happens with the appearance of hybrid construction and later with the emergence and development of reinforced concrete technology. It is also verified that wood as a constructive element, and for that reason, an element of development had great importance in national construction, with its peak being the Pombaline period, after the 1755 earthquake. In this period, the great scarcity of materials in the metropolis led to the import wood from Brazil for the reconstruction of Lisbon. This period is linked to an accentuated exploitation of forests, resulting in laws and royal decrees aimed at protecting them, guaranteeing the continued existence of profitable forests, crucial to the reconstruction effort. The following period, with the gradual loss of memory of the catastrophe, resulted in a construction that was weakened structurally as a response to a time of real estate speculation and great urban expansion. This was the moment that precluded the inexistence of the use of wood in construction. At the beginning of the 20th century and in the 30s and 40s, with the appearance and development of reinforced concrete, it became part of the great structures of the state, and it is considered a versatile material capable of resolving issues throughout the national territory. It is at this point that the wood falls into disuse and practically disappears from the new works produced.Keywords: construction history, construction in portugal, construction systems, wood construction
Procedia PDF Downloads 1231489 Phonological Characteristics of Severe to Profound Hearing Impaired Children
Authors: Akbar Darouie, Mamak Joulaie
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In regard of phonological skills development importance and its influence on other aspects of language, this study has been performed. Determination of some phonological indexes in children with hearing impairment and comparison with hearing children was the objective. A sample of convenience was selected from a rehabilitation center and a kindergarten in Karaj, Iran. Participants consisted of 12 hearing impaired and 12 hearing children (age range: 5 years and 6 months to 6 years and 6 months old). Hearing impaired children suffered from severe to profound hearing loss while three of them were cochlear implanted and the others were wearing hearing aids. Conversational speech of these children was recorded and 50 first utterances were selected to analyze. Percentage of consonant correct (PCC) and vowel correct (PVC), initial and final consonant omission error, cluster consonant omission error and syllabic structure variety were compared in two groups. Data were analyzed with t test (version 16th SPSS). Comparison between PCC and PVC averages in two groups showed a significant difference (P< 0/01). There was a significant difference about final consonant emission error (P<0/001) and initial consonant emission error (P<0/01) too. Also, the differences between two groups on cluster consonant omission were significant (P<0/001). Therefore, some changes were seen in syllabic structures in children with hearing impairment compared to typical group. This study demonstrates some phonological differences in Farsi language between two groups of children. Therefore, it seems, in clinical practices we must notice this issue.Keywords: hearing impairment, phonology, vowel, consonant
Procedia PDF Downloads 2441488 Deep Reinforcement Learning for Advanced Pressure Management in Water Distribution Networks
Authors: Ahmed Negm, George Aggidis, Xiandong Ma
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With the diverse nature of urban cities, customer demand patterns, landscape topologies or even seasonal weather trends; managing our water distribution networks (WDNs) has proved a complex task. These unpredictable circumstances manifest as pipe failures, intermittent supply and burst events thus adding to water loss, energy waste and increased carbon emissions. Whilst these events are unavoidable, advanced pressure management has proved an effective tool to control and mitigate them. Henceforth, water utilities have struggled with developing a real-time control method that is resilient when confronting the challenges of water distribution. In this paper we use deep reinforcement learning (DRL) algorithms as a novel pressure control strategy to minimise pressure violations and leakage under both burst and background leakage conditions. Agents based on asynchronous actor critic (A2C) and recurrent proximal policy optimisation (Recurrent PPO) were trained and compared to benchmarked optimisation algorithms (differential evolution, particle swarm optimisation. A2C manages to minimise leakage by 32.48% under burst conditions and 67.17% under background conditions which was the highest performance in the DRL algorithms. A2C and Recurrent PPO performed well in comparison to the benchmarks with higher processing speed and lower computational effort.Keywords: deep reinforcement learning, pressure management, water distribution networks, leakage management
Procedia PDF Downloads 911487 Microstructure and Properties of Cu-Bearing Hypereutectic High Chromium Cast Iron
Authors: Liqiang Gong, Hanguang Fu
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In order to further improve the wear resistance of Hypereutectic High Chromium Cast iron (HHCCI), the effects of different Cu contents on the microstructure and properties of HHCCI were systematically studied. It was found that with the increase of Cu content, the carbide size was refined, and the increase of Cu content led to the increase of austenite and the decrease of hardness in as-cast HHCCI. After heat treatment at 1050 °C, the hardness of HHCCI increased significantly compared with as-cast. And with the increase of Cu content, the hardness of HHCCI increased first and then decreased, and the hardness was the highest when 0.5 wt.% Cu was added. The increase of copper content promotes the precipitation of secondary carbides and makes the interface between α-Fe and M23C6-type secondary carbides a semi-coherent boundary. With the increase of Cu content, the wear loss of HHCCI decreased after heat treatment at 1050 °C, and the wear resistance improved. When the Cu content increased to 1.0 wt.%, the wear resistance of HHCCI was the best, which was 2.6 times that of copper-free HHCCI. The continued increase of copper content has no obvious effect on the wear resistance of HHCCI. In addition, a small amount of Cu tends to adsorb on the (0001) preferential growth surface of M₇C₃-type carbides, thereby refining the carbides. From the First-principles calculations, the solid solution strengthening effect of Cu on the matrix and the adsorption and refinement of carbides were revealed, and the influence mechanism on the wear resistance of HHCCI was characterized.Keywords: hypereutectic high chromium cast iron, cu alloying, carbides, wear resistance, first-principles calculations
Procedia PDF Downloads 651486 Dynamic Risk Identification Using Fuzzy Failure Mode Effect Analysis in Fabric Process Industries: A Research Article as Management Perspective
Authors: A. Sivakumar, S. S. Darun Prakash, P. Navaneethakrishnan
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In and around Erode District, it is estimated that more than 1250 chemical and allied textile processing fabric industries are affected, partially closed and shut off for various reasons such as poor management, poor supplier performance, lack of planning for productivity, fluctuation of output, poor investment, waste analysis, labor problems, capital/labor ratio, accumulation of stocks, poor maintenance of resources, deficiencies in the quality of fabric, low capacity utilization, age of plant and equipment, high investment and input but low throughput, poor research and development, lack of energy, workers’ fear of loss of jobs, work force mix and work ethic. The main objective of this work is to analyze the existing conditions in textile fabric sector, validate the break even of Total Productivity (TP), analyze, design and implement fuzzy sets and mathematical programming for improvement of productivity and quality dimensions in the fabric processing industry. It needs to be compatible with the reality of textile and fabric processing industries. The highly risk events from productivity and quality dimension were found by fuzzy systems and results are wrapped up among the textile fabric processing industry.Keywords: break even point, fuzzy crisp data, fuzzy sets, productivity, productivity cycle, total productive maintenance
Procedia PDF Downloads 3381485 Beyond Sport: Understanding the Retirement Experiences and Support Needs of Retired Elite Athletes
Authors: Nadia Jurkovic, Sarven McLinton, Alyson Crozier, Amber Mosewich, Ed O'Connor
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Retiring from elite sport can have detrimental effects on the mental health and life satisfaction of retired elite athletes. To aid in this transition, sporting organisations use retirement interventions. The aim of this study is to understand the experience of elite sport retirement from a holistic perspective, exploring the experiences of retiring athletes, retired athletes, and sport support staff. A secondary aim is used to uncover any recommendations both retiring/retired athletes and sport support staff suggest towards improving retirement programs or interventions. A total of N=15 participants took part in semi-structured interviews to explore their experiences with sport retirement. Retiring and retired elite athletes were asked about how they felt during their transition into retirement, and sport support staff were asked about their experience working with retiring athletes. Data collection and iterative qualitative analysis are still ongoing; however, it is anticipated that the final key themes to emerge will include isolation, identity loss, and lack of support, with varying sub-themes such as organisational support and family support. Relationships across and within themes will be explored within the study. The anticipated findings present retiring from elite sports as a challenging life and career transition; however, current support and resources for elite athletes are not addressing the core difficulties experienced by retiring elite athletes. The findings of this study will inform future development of new co-designed elite sport retirement interventions.Keywords: elite athlete, retired elite athlete, retirement interventions, transition into retirement, interviews
Procedia PDF Downloads 131484 An Equivalent Circuit Model Approach for Battery Pack Simulation in a Hybrid Electric Vehicle System Powertrain
Authors: Suchitra Sivakumar, Hajime Shingyouchi, Toshinori Okajima, Kyohei Yamaguchi, Jin Kusaka
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The progressing need for powertrain electrification calls for more accurate and reliable simulation models. A battery pack serves as the most vital component for energy storage in an electrified powertrain. Hybrid electric vehicles (HEV) do not behave the same way as they age, and there are several environmental factors that account for the degradation of the battery on a system level. Therefore, in this work, a battery model was proposed to study the state of charge (SOC) variation and the internal dynamic changes that contribute to aging and performance degradation in HEV batteries. An equivalent circuit battery model (ECM) is built using MATLAB Simulink to investigate the output characteristics of the lithium-ion battery. The ECM comprises of circuit elements like a voltage source, a series resistor and a parallel RC network connected in series. A parameter estimation study is conducted on the ECM to study the dependencies of the circuit elements with the state of charge (SOC) and the terminal voltage of the battery. The battery model is extended to simulate the temperature dependence of the individual battery cell and the battery pack with the environment. The temperature dependence model accounts for the heat loss due to internal resistance build up in the battery pack during charging, discharging, and due to atmospheric temperature. The model was validated for a lithium-ion battery pack with an independent drive cycle showing a voltage accuracy of 4% and SOC accuracy of about 2%.Keywords: battery model, hybrid electric vehicle, lithium-ion battery, thermal model
Procedia PDF Downloads 2981483 Thermal Analysis and Optimization of a High-Speed Permanent Magnet Synchronous Motor with Toroidal Windings
Authors: Yuan Wan, Shumei Cui, Shaopeng Wu
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Toroidal windings were taken advantage of to reduce of axial length of the motor, so as to match the applications that have severe restrictions on the axial length. But slotting in the out edge of the stator will decrease the heat-dissipation capacity of the water cooling of the housing. Besides, the windings in the outer slots will increase the copper loss, which will further increase the difficult for heat dissipation of the motor. At present, carbon-fiber composite retaining sleeve are increasingly used to be mounted over the magnets to ensure the rotor strength at high speeds. Due to the poor thermal conductivity of carbon-fiber sleeve, the cooling of the rotor becomes very difficult, which may result in the irreversible demagnetization of magnets for the excessively high temperature. So it is necessary to analyze the temperature rise of such motor. This paper builds a computational fluid dynamic (CFD) model of a toroidal-winding high-speed permanent magnet synchronous motor (PMSM) with water cooling of housing and forced air cooling of rotor. Thermal analysis was carried out based on the model and the factors that affects the temperature rise were investigated. Then thermal optimization for the prototype was achieved. Finally, a small-size prototype was manufactured and the thermal analysis results were verified.Keywords: thermal analysis, temperature rise, toroidal windings, high-speed PMSM, CFD
Procedia PDF Downloads 4931482 Biogas as a Renewable Energy Fuel: A Review of Biogas Upgrading, Utilization and Storage
Authors: Imran Ullah Khana, Mohd Hafiz Dzarfan Othmanb, Haslenda Hashima, Takeshi Matsuurad, A. F. Ismailb, M. Rezaei-DashtArzhandib, I. Wan Azelee
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Biogas upgrading is a widely studied and discussed topic, and its utilization as a natural gas substitute has gained significant attention in recent years. The production of biomethane provides a versatile application in both heat and power generation and as a vehicular fuel. This paper systematically reviews the state of the art of biogas upgrading technologies with upgrading efficiency, methane (CH4) loss, environmental effect, development and commercialization, and challenges in terms of energy consumption and economic assessment. The market situation for biogas upgrading has changed rapidly in recent years, giving membrane separation a significant market share with traditional biogas upgrading technologies. In addition, the potential utilization of biogas, efficient conversion into bio-compressed natural gas (bio-CNG), and storage systems are investigated in depth. Two storing systems for bio-CNG at filling stations, namely buffer and cascade storage systems are used. The best storage system should be selected on the basis of the advantages of both systems. Also, the fuel economy and mass emissions for bio-CNG and CNG-filled vehicles are studied. There is the same fuel economy and less carbon dioxide (CO2) emission for bio-CNG. Based on the results of comparisons between the technical features of upgrading technologies, various specific requirements for biogas utilization and the relevant investment, and operating and maintenance costs, future recommendations are made for biogas upgrading.Keywords: biogas upgrading, cost, utilization, bio-CNG, storage, energy
Procedia PDF Downloads 501481 Improvement of Heat Pipe Thermal Performance in H-VAC Systems Using CFD Modeling
Authors: H. Shokouhmand, A. Ghanami
Abstract:
Heat pipe is simple heat transfer device which combines the conduction and phase change phenomena to control the heat transfer without any need for external power source. At hot surface of heat pipe, the liquid phase absorbs heat and changes to vapor phase. The vapor phase flows to condenser region and with the loss of heat changes to liquid phase. Due to gravitational force the liquid phase flows to evaporator section. In HVAC systems the working fluid is chosen based on the operating temperature. The heat pipe has significant capability to reduce the humidity in HVAC systems. Each HVAC system which uses heater, humidifier or dryer is a suitable nominate for the utilization of heat pipes. Generally heat pipes have three main sections: condenser, adiabatic region and evaporator.Performance investigation and optimization of heat pipes operation in order to increase their efficiency is crucial. In present article, a parametric study is performed to improve the heat pipe performance. Therefore, the heat capacity of heat pipe with respect to geometrical and confining parameters is investigated. For the better observation of heat pipe operation in HVAC systems, a CFD simulation in Eulerian- Eulerian multiphase approach is also performed. The results show that heat pipe heat transfer capacity is higher for water as working fluid with the operating temperature of 340 K. It is also showed that the vertical orientation of heat pipe enhances it’s heat transfer capacity used in the abstract.Keywords: heat pipe, HVAC system, grooved heat pipe, CFD simulation
Procedia PDF Downloads 4251480 Disaster Management and Resilience: A Conceptual Synthesis of Local
Authors: Oshienemen Albert, Dilanthi Amaratunga, Richard Haigh
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Globally, disasters of any form can affect the environment, built environment, the waterways, societies, nations and communities in diverse areas. The such impacts could cut across, economic loss, social setting, cultural and livelihood structures of affected population. Thus, the raise of disaster impacts across developing nations are alarming with decades impact due to the lack of hard and soft infrastructural development across communities, inconsistency in the governmental policy and implementation, making it difficult for disaster affected communities to bounce back when necessary, especially in Nigeria. The Nigeria disasters, especially oil spillages have affected diverse communities across the Niger Delta region for decades with little or nothing as external support for the broken livelihood structure, cultural and economic damages of the people. Though, in the spirit of contribution to the communities affected by oil spill and negative consequence of petroleum production, the federal government at different times established some impressionistic bodies and agencies to oversee the affairs of the region as with regards to oil spillages and development. Thus, the agencies contributions are yet to manifest in practice. This amplifies the quest for the structural clarities of the management systems and the resilience’s of the communities, to better equip the communities for any such disaster. Therefore, the study sets to explore the Nigerian disaster management systems and resilience concept at local community level. Thus, desk-based approach and interviews are employed for the synthesis while, drawing conclusion and recommendations.Keywords: disaster, community, management, resilience
Procedia PDF Downloads 1851479 Production Value, Constraints, and Opportunities in East African Freshwater Fisheries: Systematic Review
Authors: Alamrew Eyayu, Abebe Getahun, James Last Keyombe
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Demand for fish continued to grow worldwide while production from capture fisheries has decreased. In the Eastern African Region (EAR), the open-access nature of capture fisheries has resulted in illegal fishing. Within communities engaged in fishing, small-scale fisheries support food security strategies and sustain livelihoods. Despite the role of fisheries in EAR, inland fisheries are vulnerable to loss, and management solutions authorized for inland fisheries are inadequate. This review investigates production potential, challenges, opportunities, and management of inland fisheries in the EAR. It is therefore expected that in aquaculture promising areas, the EAR will turn to depend more on aquaculture to meet the extended needs and supply gaps created as a result of capture fisheries shortfalls. However, aquaculture is still in its infant stage in the region, and there exists no adequate aquaculture policy framework and funds in some EAR (e.g., Ethiopia, Somalia). Stakeholders at all levels should entertain the importance of fishery-based activities for food security in EAR. As a result, easily implemented and community-oriented fisheries legislative documents need to be prepared for advancing sustainable fisheries management. Legislative documents might consider techniques of continual catch statistics (consider small water bodies as much as possible) of inland fisheries and enforcing existing laws to manage illegal fishing activities to accustom sustainable development of inland capture fisheries.Keywords: aquaculture, capture fisheries, East Africa, fisheries management
Procedia PDF Downloads 251478 Improvement of Heat Pipes Thermal Performance in H-VAC Systems Using CFD Modeling
Authors: H. Shokouhmand, A. Ghanami
Abstract:
Heat pipe is simple heat transfer device which combines the conduction and phase change phenomena to control the heat transfer without any need for external power source. At hot surface of heat pipe, the liquid phase absorbs heat and changes to vapor phase. The vapor phase flows to condenser region and with the loss of heat changes to liquid phase. Due to gravitational force the liquid phase flows to evaporator section.In HVAC systems the working fluid is chosen based on the operating temperature. The heat pipe has significant capability to reduce the humidity in HVAC systems. Each HVAC system which uses heater, humidifier or dryer is a suitable nominate for the utilization of heat pipes. Generally heat pipes have three main sections: condenser, adiabatic region and evaporator.Performance investigation and optimization of heat pipes operation in order to increase their efficiency is crucial. In present article, a parametric study is performed to improve the heat pipe performance. Therefore, the heat capacity of heat pipe with respect to geometrical and confining parameters is investigated. For the better observation of heat pipe operation in HVAC systems, a CFD simulation in Eulerian- Eulerian multiphase approach is also performed. The results show that heat pipe heat transfer capacity is higher for water as working fluid with the operating temperature of 340 K. It is also showed that the vertical orientation of heat pipe enhances it’s heat transfer capacity used in the abstract.Keywords: heat pipe, HVAC system, grooved heat pipe, heat pipe limits
Procedia PDF Downloads 3641477 Experimental Investigations on Group Interaction Effects of Laterally Loaded Piles in Submerged Sand
Authors: Jasaswini Mishra, Ashim K. Dey
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This paper aims to investigate the group interaction effects of laterally loaded pile groups driven into a medium dense sand layer in submerged state. Static lateral load tests were carried out on pile groups consisting of varying number of piles and at different spacings. The test setup consists of a load cell (500 kg capacity) and an LVDT (50 mm) to measure the load and pile head deflection respectively. The piles were extensively instrumented with strain gauges so as to study the variation of soil resistance within the group. The bending moments at various depths were calculated from strain gauge data and these curves were fitted using a higher order polynomial in order to get 'p-y' curves. A comparative study between a single pile and a pile under a group has also been done for a better understanding of the group effect. It is observed that average load per pile is significantly reduced relative to single pile and it decreases with increase in the number of piles in a pile group. The loss of efficiency of the piles in the group, commonly referred to as "shadowing" effect, has been expressed by the use of a 'p-multiplier'. Leading rows carries greater amount of load when compared with the trailing rows. The variations of bending moment with depth for different rows of pile within a group and different spacing have been analyzed and compared with that of a single pile. p multipliers within different rows in a pile group were evaluated from the experimental study.Keywords: group action, laterally loaded piles, p-multiplier, strain gauge
Procedia PDF Downloads 2421476 Behave Imbalances Comparative Checking of Children with and without Fathers between the Ages of 7 to 11 in Rasht
Authors: Farnoush Haghanipour
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Objective: Father loss as one of the major stress factor, can causethe mental imbalances in children. It's clear that children's family condition of lacking a father is very clearly different from the condition of having a father. The goal of this research is to examine mental imbalances comparative checking in complete form and in five subsidiary categories as aggression, stress and depression, social incompatibility, anti-social behavior, and attention deficit imbalances (wackiness) do between children without father and normal ones. Method: This research is in descriptive and analytical method that reimburse to checking mental imbalances from 50 children that are student in one zone of Rasht’s education and nurture office. Material of this research is RATER behavior questionnaire (teacher form) and data analyses were did by SPSS software. Results: The results showed that there are clear different in relation with behavior imbalances between have father children and children without father and in children without a father behavior imbalance is more. Also showed that there is clearly a difference in aggression, stress, and depression and social incompatibility between children without and without fathers, and in children without a father the proportion increases. However, in antisocial behaviours and attention deficit imbalances there are not a clear difference between them. Conclusion: With upper amount of imbalance behaviour detection in children without fathers compared with children with fathers, it is essential that practitioners of society hygienic and remedy put efforts in order to primary and secondary prevention, for mental health of this group of society.Keywords: child, behave imbalances, children without father, mental imbalances
Procedia PDF Downloads 2561475 The Impact of Stigma on the Course of Mental Illness: A Brief Review
Authors: Mariana Mangas, Yaroslava Martins, Ana Matos Pires
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Introduction: Stigmatization is a common problem to overcome for people suffering from chronic diseases. It usually follows mental disorders and complicates the course of illness and reduces quality of life for people with mental illness. Objective: unsystematic review concerning stigma and mental illness, its impact on psychiatric disease and strategies to eradicate stigma. Methods: A search was conducted on PubMed, using keywords 'stigma' and 'mental illness'. Results and Discussion: Stigma is a psychosocial process that identifies individuals by the negative label of their differences. Stigma often brings a loss of occupational success and social support, reduced functioning and lower quality of life. The sense of stigma is common in individuals with mental illness and has considerable negative repercussions: delays treatment achievement, promotes social isolation, stress and maladaptive coping behaviors and it is associated with higher symptom levels, placing these individuals at higher risk for a poorer outcome and prognoses. Conclusion: Given the interrelation between stigma, symptoms, treatment seeking and disease management, stigma is a key construct in mental illness upon which anti-stigma initiatives may have considerable therapeutic potential. It will take multidisciplinary interventions to overcome mental illness stigma, including changes in social policy, attitudes and practices among mental health professionals, liaison between general public and people with a mental illness under conditions of equity and parity, family support, and easy access to evidence-based treatments.Keywords: discrimination, stigma, mental illness, quality of life
Procedia PDF Downloads 3391474 Comparative Study of Heat Transfer Capacity Limits of Heat Pipes
Authors: H. Shokouhmand, A. Ghanami
Abstract:
Heat pipe is simple heat transfer device which combines the conduction and phase change phenomena to control the heat transfer without any need for external power source. At hot surface of heat pipe, the liquid phase absorbs heat and changes to vapor phase. The vapor phase flows to condenser region and with the loss of heat changes to liquid phase. Due to gravitational force the liquid phase flows to evaporator section.In HVAC systems the working fluid is chosen based on the operating temperature. The heat pipe has significant capability to reduce the humidity in HVAC systems. Each HVAC system which uses heater, humidifier or dryer is a suitable nominate for the utilization of heat pipes. Generally heat pipes have three main sections: condenser, adiabatic region and evaporator.Performance investigation and optimization of heat pipes operation in order to increase their efficiency is crucial. In present article, a parametric study is performed to improve the heat pipe performance. Therefore, the heat capacity of heat pipe with respect to geometrical and confining parameters is investigated. For the better observation of heat pipe operation in HVAC systems, a CFD simulation in Eulerian- Eulerian multiphase approach is also performed. The results show that heat pipe heat transfer capacity is higher for water as working fluid with the operating temperature of 340 K. It is also showed that the vertical orientation of heat pipe enhances it’s heat transfer capacity.Keywords: heat pipe, HVAC system, grooved Heat pipe, heat pipe limits
Procedia PDF Downloads 4211473 Fabrication of Electrospun Carbon Nanofibers-Reinforced Chitosan-Based Hydrogel for Environmental Applications
Authors: Badr M. Thamer
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The use of hydrogels as adsorbents for pollutants removal from wastewater is limited due to their high swelling properties and the difficulty in recovering them after the adsorption process. To overcome these problems, a new hydrogel nanocomposite based on chitosan-g-polyacrylic acid/oxidized electrospun carbon nanofibers (CT-g-PAA/O-ECNFs) was prepared by in-situ grafting polymerization process. The prepared hydrogel nanocomposite was used as a novel effective and highly reusable adsorbent for the removal of methylene blue (MB) from polluted water with low cost. The morphology and the structure of CT-g-PAA/O-ECNFs were investigated by numerous techniques. The effect of incorporating O-ECNFs on the swelling capability of the prepared hydrogel was explored in distillated water and MB solution at normal pH. The effect of parameters including the ratio of O-ECNFs, contact time, pH, initial concentration, and temperature on the adsorption process were explored. The adsorption isotherm and kinetic were studied by numerous non-linear models. The obtained results confirmed that the incorporation of O-ECNFs into the hydrogel network improved its ability towards MB dye removal with decreasing their swelling capacity. The adsorption process depends on the pH value of the dye solution. Additionally, the adsorption and kinetic results were fitted using the Freundlich isotherm model and pseudo second order model (PSO), respectively. Moreover, the new adsorbents can be recycled for at least five cycles keeping its adsorption capacity and can be easily recovered without loss in its initial weight.Keywords: carbon nanofibers, hydrogels, nanocomposites, water treatment
Procedia PDF Downloads 1471472 The Internet of Things: A Survey of Authentication Mechanisms, and Protocols, for the Shifting Paradigm of Communicating, Entities
Authors: Nazli Hardy
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Multidisciplinary application of computer science, interactive database-driven web application, the Internet of Things (IoT) represents a digital ecosystem that has pervasive technological, social, and economic, impact on the human population. It is a long-term technology, and its development is built around the connection of everyday objects, to the Internet. It is estimated that by 2020, with billions of people connected to the Internet, the number of connected devices will exceed 50 billion, and thus IoT represents a paradigm shift in in our current interconnected ecosystem, a communication shift that will unavoidably affect people, businesses, consumers, clients, employees. By nature, in order to provide a cohesive and integrated service, connected devices need to collect, aggregate, store, mine, process personal and personalized data on individuals and corporations in a variety of contexts and environments. A significant factor in this paradigm shift is the necessity for secure and appropriate transmission, processing and storage of the data. Thus, while benefits of the applications appear to be boundless, these same opportunities are bounded by concerns such as trust, privacy, security, loss of control, and related issues. This poster and presentation look at a multi-factor authentication (MFA) mechanisms that need to change from the login-password tuple to an Identity and Access Management (IAM) model, to the more cohesive to Identity Relationship Management (IRM) standard. It also compares and contrasts messaging protocols that are appropriate for the IoT ecosystem.Keywords: Internet of Things (IoT), authentication, protocols, survey
Procedia PDF Downloads 2991471 Improve Heat Pipes Thermal Performance In H-VAC Systems Using CFD Modeling
Authors: A. Ghanami, M.Heydari
Abstract:
Heat pipe is simple heat transfer device which combines the conduction and phase change phenomena to control the heat transfer without any need for external power source. At hot surface of heat pipe, the liquid phase absorbs heat and changes to vapor phase. The vapor phase flows to condenser region and with the loss of heat changes to liquid phase. Due to gravitational force the liquid phase flows to evaporator section. In HVAC systems the working fluid is chosen based on the operating temperature. The heat pipe has significant capability to reduce the humidity in HVAC systems. Each HVAC system which uses heater, humidifier or dryer is a suitable nominate for the utilization of heat pipes. Generally heat pipes have three main sections: condenser, adiabatic region and evaporator. Performance investigation and optimization of heat pipes operation in order to increase their efficiency is crucial. In present article, a parametric study is performed to improve the heat pipe performance. Therefore, the heat capacity of heat pipe with respect to geometrical and confining parameters is investigated. For the better observation of heat pipe operation in HVAC systems, a CFD simulation in Eulerian- Eulerian multiphase approach is also performed. The results show that heat pipe heat transfer capacity is higher for water as working fluid with the operating temperature of 340 K. It is also showed that the vertical orientation of heat pipe enhances it’s heat transfer capacity.used in the abstract.Keywords: Heat pipe, HVAC system, Grooved Heat pipe, Heat pipe limits.
Procedia PDF Downloads 4821470 The Estimation of Bird Diversity Loss and Gain as an Impact of Oil Palm Plantation: Study Case in KJNP Estate Riau Province
Authors: Yanto Santosa, Catharina Yudea
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The rapid growth of oil palm industry in Indonesia raised many negative accusations from various parties, who said that oil palm plantation is damaging the environment and biodiversity, including birds. Since research on oil palm plantation impacts on bird diversity is still limited, this study needs to be developed in order to gain further learning and understanding. Data on bird diversity were collected in March 2018 in KJNP Estate, Riau Province using strip transect method on five different land cover types (young, intermediate, and old growth of oil palm plantation, high conservation value area, and crops field or the baseline). The observations were conducted simultaneously, with three repetitions. The result shows that the baseline has 19 species of birds and land cover after the oil palm plantation has 39 species. HCV (high conservation value) area has the highest increase in diversity value. Oil palm plantation has changed the composition of bird species. The highest similarity index is shown by young growth oil palm land cover with total score 0.65, meanwhile the lowest similarity index with total score 0.43 is shown by HCV area. Overall, the existence of oil palm plantation made a positive impact by increasing bird species diversity, with total 23 species gained and 3 species lost.Keywords: bird diversity, crops field, impact of oil palm plantation, KJNP estate
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