Search results for: integration of renewable energy
2737 In situ Modelling of Lateral-Torsional Vibration of a Rotor-Stator with Multiple Parametric Excitations
Authors: B. X. Tchomeni, A. A. Alugongo, L. M. Masu
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This paper presents a 4-DOF nonlinear model of a cracked of Laval rotor established based on Energy Principles. The model has been used to simulate coupled torsional-lateral response of the cracked rotor stator-system with multiple parametric excitations, namely, rotor-stator-rub, a breathing transverse crack, unbalanced mass, and an axial force. Nonlinearity due to a “breathing” crack is incorporated by considering a simple hinge model which is suitable for small breathing crack. The vibration response of a cracked rotor passing through its critical speed with rotor-stator interaction is analyzed, and an attempt for crack detection and monitoring explored. Effects of unbalanced eccentricity with phase and acceleration are investigated. By solving the motion equations, steady-state vibration response is obtained in presence of several rotor faults. The presence of a crack is observable in the power spectrum despite the excitation by the axial force and rotor-stator rub impact. Presented results are consistent with existing literature and could be adopted into rotor condition monitoring strategiesKeywords: rotor, crack, rubbing, axial force, non linear
Procedia PDF Downloads 3942736 The Impact of System Cascading Collapse and Transmission Line Outages to the Transfer Capability Assessment
Authors: Nur Ashida Salim, Muhammad Murtadha Othman, Ismail Musirin, Mohd Salleh Serwan
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Uncertainty of system operating conditions is one of the causative reasons which may render to the instability of a transmission system. This will encumber the performance of transmission system to efficiently transmit the electrical power between areas. For that reason, accurate assessment of Transmission Reliability Margin (TRM) is essential in order to ensure effective power transfer between areas during the occurrence of system uncertainties. The power transfer is also called as the Available Transfer Capability (ATC) in which it is the information required by the utilities and marketers to instigate selling and buying the electric energy. This paper proposes a computationally effective approach to estimate TRM and ATC by considering the uncertainties of system cascading collapse and transmission line outages which is identified as the main reasons in power system instability. In accordance to the results that have been obtained, the proposed method is essential for the transmission providers which could help the power marketers and planning sectors in the operation and reserving transmission services based on the ATC calculated.Keywords: system cascading collapse, transmission line outages, transmission reliability margin, available transfer capability
Procedia PDF Downloads 4192735 Reliability Analysis for Cyclic Fatigue Life Prediction in Railroad Bolt Hole
Authors: Hasan Keshavarzian, Tayebeh Nesari
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Bolted rail joint is one of the most vulnerable areas in railway track. A comprehensive approach was developed for studying the reliability of fatigue crack initiation of railroad bolt hole under random axle loads and random material properties. The operation condition was also considered as stochastic variables. In order to obtain the comprehensive probability model of fatigue crack initiation life prediction in railroad bolt hole, we used FEM, response surface method (RSM), and reliability analysis. Combined energy-density based and critical plane based fatigue concept is used for the fatigue crack prediction. The dynamic loads were calculated according to the axle load, speed, and track properties. The results show that axle load is most sensitive parameter compared to Poisson’s ratio in fatigue crack initiation life. Also, the reliability index decreases slowly due to high cycle fatigue regime in this area.Keywords: rail-wheel tribology, rolling contact mechanic, finite element modeling, reliability analysis
Procedia PDF Downloads 3742734 Architectural Geometric Shapes That Have Changed the World: Heydar Aliyev Centre vs. the Pyramid of Quéops
Authors: Ayda Kurtulus
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Heydar Aliyev Centre and Quéops Pyramid are two contrasting examples of sacred geometry perceived as metaphorical alchemy by linking cosmos and earth. Zaha Hadid’s modern building has a wave-like shape and semi-circular alternations that show fluidity and movement, while The Great Pyramid of Giza is triangular. The centre is reminding of the shape of planets, an attempt to regain the balance lost in the modern-day capitalist world, while the Great Pyramid of Giza represents a vortex of energy that connects heaven and earth, harmony and balance. The sacred geometric shapes link the past and the future through God and Ra, humanism and spiritualism in an architectural evolution continuum, mind and spirit into one. An analysis of two geometrical forms, a semi-circle, and a triangle, were carried out through a comprehensive literature review, indicating that behind the materialistic perceptual beauty of buildings, ancient and contemporary, there are mathematical and sacred geometrical constructions that add value to one superficiality can interpret.Keywords: architectural shapes, The Great Pyramid of Giza, Heydar Aliyev Centre, sacred geometry, philosophy
Procedia PDF Downloads 952733 Dynamic High-Rise Moment Resisting Frame Dissipation Performances Adopting Glazed Curtain Walls with Superelastic Shape Memory Alloy Joints
Authors: Lorenzo Casagrande, Antonio Bonati, Ferdinando Auricchio, Antonio Occhiuzzi
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This paper summarizes the results of a survey on smart non-structural element dynamic dissipation when installed in modern high-rise mega-frame prototypes. An innovative glazed curtain wall was designed using Shape Memory Alloy (SMA) joints in order to increase the energy dissipation and enhance the seismic/wind response of the structures. The studied buildings consisted of thirty- and sixty-storey planar frames, extracted from reference three-dimensional steel Moment Resisting Frame (MRF) with outriggers and belt trusses. The internal core was composed of a CBF system, whilst outriggers were placed every fifteen stories to limit second order effects and inter-storey drifts. These structural systems were designed in accordance with European rules and numerical FE models were developed with an open-source code, able to account for geometric and material nonlinearities. With regard to the characterization of non-structural building components, full-scale crescendo tests were performed on aluminium/glass curtain wall units at the laboratory of the Construction Technologies Institute (ITC) of the Italian National Research Council (CNR), deriving force-displacement curves. Three-dimensional brick-based inelastic FE models were calibrated according to experimental results, simulating the fac¸ade response. Since recent seismic events and extreme dynamic wind loads have generated the large occurrence of non-structural components failure, which causes sensitive economic losses and represents a hazard for pedestrians safety, a more dissipative glazed curtain wall was studied. Taking advantage of the mechanical properties of SMA, advanced smart joints were designed with the aim to enhance both the dynamic performance of the single non-structural unit and the global behavior. Thus, three-dimensional brick-based plastic FE models were produced, based on the innovated non-structural system, simulating the evolution of mechanical degradation in aluminium-to-glass and SMA-to-glass connections when high deformations occurred. Consequently, equivalent nonlinear links were calibrated to reproduce the behavior of both tested and smart designed units, and implemented on the thirty- and sixty-storey structural planar frame FE models. Nonlinear time history analyses (NLTHAs) were performed to quantify the potential of the new system, when considered in the lateral resisting frame system (LRFS) of modern high-rise MRFs. Sensitivity to the structure height was explored comparing the responses of the two prototypes. Trends in global and local performance were discussed to show that, if accurately designed, advanced materials in non-structural elements provide new sources of energy dissipation.Keywords: advanced technologies, glazed curtain walls, non-structural elements, seismic-action reduction, shape memory alloy
Procedia PDF Downloads 3222732 'Sea Power: Concept, Influence and Securitization'; the Nigerian Navy's Role in a Developing State like Nigeria
Authors: William Abiodun Duyile
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It is common knowledge that marine food has always been found from the sea, energy can also be found underneath and, to a growing extent; other mineral resources have come from the sea spaces. It is the importance of the sea and the sea lines of communication to littoral nations that has made concepts such as sea power, naval power, etc., significant to them. The study relied on documentary data. The documentary data were sourced from government annual departmental reports, newspapers and correspondence. The secondary sources used were subjected to internal and external criticism for authentication, and then to textual and contextual analyses. The study found that the differential level of seamanship amongst states defined their relationship. It was sea power that gave some states an edge over the others. The study proves that over the ages sea power has been core to the development of States or Empires. The study found that the Nigerian Navy was centre to Nigeria’s conquest of the littoral areas of Biafra, like Bonny, Port-Harcourt, and Calabar; it was also an important turning point of the Nigerian civil war since by it Biafra became landlocked. The research was able to identify succinctly the Nigerian Navy’s contribution to the security and development of the Nigerian State.Keywords: sea power, naval power, land locked states, warship
Procedia PDF Downloads 1312731 Using Businesses for Governance and Creating Sustainable Cities
Authors: Parisa Toloue Hayat Azar
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Businesses have been playing an important role in the economic growth and social welfare of cities; however, they generally have negative reputations regarding their impact on environmental issues regarding sustainability. However, some believe that by incorporating strategic Corporate Social Responsibility (CSR) activities, businesses will be able to solve problems in society, including environmental ones. Besides economic, social and environmental aspects, governance is another essential pillar for creating sustainable communities and cities. Governance plays a key role in the success of sustainable projects or creating long lasting legacies; an example of this can be creating circular supply chain with collaboration between different businesses, which in the end results in positive economic, social and environmental outcomes for everyone. Governance is a very important parameter in creating the legacy of low carbon and environmentally friendly city due to the fact that, besides building energy efficient buildings and infrastructure, citizens who are also part of the success of this system should know about how to behave and collaborate with others to make the system work. By deploying the philosophy of cultural historical activity theory, this paper explains how influential businesses have been and can be still used as a mediating tool for governance purposes, and succeed in creating shared value and lasting legacy within society.Keywords: business, governance, CSR, sustainability
Procedia PDF Downloads 2222730 Assessment of Current and Future Opportunities of Chemical and Biological Surveillance of Wastewater for Human Health
Authors: Adam Gushgari
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The SARS-CoV-2 pandemic has catalyzed the rapid adoption of wastewater-based epidemiology (WBE) methodologies both domestically and internationally. To support the rapid scale-up of pandemic-response wastewater surveillance systems, multiple federal agencies (i.e. US CDC), non-government organizations (i.e. Water Environment Federation), and private charities (i.e. Bill and Melinda Gates Foundation) have funded over $220 million USD supporting development and expanding equitable access of surveillance methods. Funds were primarily distributed directly to municipalities under the CARES Act (90.6%), followed by academic projects (7.6%), and initiatives developed by private companies (1.8%). In addition to federal funding for wastewater monitoring primarily conducted at wastewater treatment plants, state/local governments and private companies have leveraged wastewater sampling to obtain health and lifestyle data on student, prison inmate, and employee populations. We explore the viable paths for expansion of the WBE m1ethodology across a variety of analytical methods; the development of WBE-specific samplers and real-time wastewater sensors; and their application to various governments and private sector industries. Considerable investment in, and public acceptance of WBE suggests the methodology will be applied to other future notifiable diseases and health risks. Early research suggests that WBE methods can be applied to a host of additional “biological insults” including communicable diseases and pathogens, such as influenza, Cryptosporidium, Giardia, mycotoxin exposure, hepatitis, dengue, West Nile, Zika, and yellow fever. Interest in chemical insults is also likely, providing community health and lifestyle data on narcotics consumption, use of pharmaceutical and personal care products (PPCP), PFAS and hazardous chemical exposure, and microplastic exposure. Successful application of WBE to monitor analytes correlated with carcinogen exposure, community stress prevalence, and dietary indicators has also been shown. Additionally, technology developments of in situ wastewater sensors, WBE-specific wastewater samplers, and integration of artificial intelligence will drastically change the landscape of WBE through the development of “smart sewer” networks. The rapid expansion of the WBE field is creating significant business opportunities for professionals across the scientific, engineering, and technology industries ultimately focused on community health improvement.Keywords: wastewater surveillance, wastewater-based epidemiology, smart cities, public health, pandemic management, substance abuse
Procedia PDF Downloads 952729 The Use of Culture as a Campaign Method in Indonesian Parliamentary Election
Authors: Azza Habibullah
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The principal objective of this paper is to show the use of participatory culture in the parliamentarian campaign. The use of this method has always been non-popular amongst the parliamentarian candidates due to the amount of times and energy that they need to spent with the constituents. However, due to many parliamentarian corruption cases in the last five years period, some political party have been losing peoples trust. That political party trust lost had also affecting the parliamentarian candidates electability, so they invent some creative campaign method that involving their constituent with more intimates and friendly environment. In this paper, an observation is done to a parliamentarian candidate from Partai Keadilan Sejahtera (Prosperous Justice Party) in Bandung and Cimahi City area, West Java. This Parliamentraian candidate is known for her personal-approach campaign method such as a puppet show, hanging out with group of ex-bike gang leaders, and going fishing with the constituent. This paper will compare her method with other parliamentarian candidates from the same party as her that mostly use mainstream campaign method such as open speech, print media, an other one way campaign method. While the other parliamentarian candidates failed to reach the parliamentarian threshold, the participatory method had proven as an effective method.Keywords: participatory culture, Indonesian parliamentary election, Prosperous Justice Party, electability
Procedia PDF Downloads 2552728 A Bio-Inspired Approach for Self-Managing Wireless Sensor and Actor Networks
Authors: Lyamine Guezouli, Kamel Barka, Zineb Seghir
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Wireless sensor and actor networks (WSANs) present a research challenge for different practice areas. Researchers are trying to optimize the use of such networks through their research work. This optimization is done on certain criteria, such as improving energy efficiency, exploiting node heterogeneity, self-adaptability and self-configuration. In this article, we present our proposal for BIFSA (Biologically-Inspired Framework for Wireless Sensor and Actor networks). Indeed, BIFSA is a middleware that addresses the key issues of wireless sensor and actor networks. BIFSA consists of two types of agents: sensor agents (SA) that operate at the sensor level to collect and transport data to actors and actor agents (AA) that operate at the actor level to transport data to base stations. Once the sensor agent arrives at the actor, it becomes an actor agent, which can exploit the resources of the actors and vice versa. BIFSA allows agents to evolve their genetic structures and adapt to the current network conditions. The simulation results show that BIFSA allows the agents to make better use of all the resources available in each type of node, which improves the performance of the network.Keywords: wireless sensor and actor networks, self-management, genetic algorithm, agent.
Procedia PDF Downloads 772727 Vibrancy in The City: The Problem of Sidi-Gaber Station Zone in Alexandria, Egypt
Authors: Gihan Mosaad, Bakr Gomaa, Rana Elbadri
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Modern parts of Alexandria city lack in vibrancy, causing a number of problems such as urban areas with poor security measures as well as weak economic state. Vibrancy provides a livable, attractive and secure environments; it also boosts the city’s economy and social life. Vibrant city is a city full of energy and life. To achieve this, a number of resources are needed; namely specific urban density, the availability of alternative modes of transportation and finally diversity of land-uses. Literature review shows no comprehensive study that assesses vibrancy in the streets of modern Alexandria. This study aims to measure the vibrancy potential in Sidi-Gaber station area thought the assessment of existing resources performance. Methods include literature reviews, surveying of existing case, questionnaire as well as GIS techniques. Expected results include GIS maps defining the vibrancy potentials in land use, density and statistical study regarding public transportation use in the area.Keywords: Alexandria, density, mixed use, transportation, vibrancy
Procedia PDF Downloads 2762726 The Impact of the Virtual Learning Environment on Teacher's Pedagogy and Student's Learning in Primary School Setting
Authors: Noor Ashikin Omar
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The rapid growth and advancement in information and communication technology (ICT) at a global scene has greatly influenced and revolutionised interaction amongst society. The use of ICT has become second nature in managing everyday lives, particularly in the education environment. Traditional learning methods of using blackboards and chalks have been largely improved by the use of ICT devices such as interactive whiteboards and computers in school. This paper aims to explore the impacts of virtual learning environments (VLE) on teacher’s pedagogy and student’s learning in primary school settings. The research was conducted in two phases. Phase one of this study comprised a short interview with the school’s senior assistants to examine issues and challenges faced during planning and implementation of FrogVLE in their respective schools. Phase two involved a survey of a number of questionnaires directed to three major stakeholders; the teachers, students and parents. The survey intended to explore teacher’s and student’s perspective and attitude towards the use of VLE as a teaching and learning medium and as a learning experience as a whole. In addition, the survey from parents provided insights on how they feel towards the use of VLE for their child’s learning. Collectively, the two phases enable improved understanding and provided observations on factors that had affected the implementation of the VLE into primary schools. This study offers the voices of the students which were frequently omitted when addressing innovations as well as teachers who may not always be heard. It is also significant in addressing the importance of teacher’s pedagogy on students’ learning and its effects to enable more effective ICT integration with a student-centred approach. Finally, parental perceptions in the implementation of VLE in supporting their children’s learning have been implicated as having a bearing on educational achievement. The results indicate that the all three stakeholders were positive and highly supportive towards the use of VLE in schools. They were able to understand the benefits of moving towards the modern method of teaching using ICT and accept the change in the education system. However, factors such as condition of ICT facilities at schools and homes as well as inadequate professional development for the teachers in both ICT skills and management skills hindered exploitation of the VLE system in order to fully utilise its benefits. Social influences within different communities and cultures and costs of using the technology also has a significant impact. The findings of this study are important to the Malaysian Ministry of Education because it informs policy makers on the impact of the Virtual Learning Environment (VLE) on teacher’s pedagogy and learning of Malaysian primary school children. The information provided to policy makers allows them to make a sound judgement and enables an informed decision making.Keywords: attitudes towards virtual learning environment (VLE), parental perception, student's learning, teacher's pedagogy
Procedia PDF Downloads 2002725 Solvent Free Microwave Extraction of Essential Oils: A Clean Chemical Processing in the Teaching and Research Laboratory
Authors: M. A. Ferhat, M. N. Boukhatem, F. Chemat
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Microwave Clevenger or microwave accelerated distillation (MAD) is a combination of microwave heating and distillation, performed at atmospheric pressure without added any solvent or water. Isolation and concentration of volatile compounds are performed by a single stage. MAD extraction of orange essential oil was studied using fresh orange peel from Valencia late cultivar oranges as the raw material. MAD has been compared with a conventional technique, which used a Clevenger apparatus with hydro-distillation (HD). MAD and HD were compared in term of extraction time, yields, chemical composition and quality of the essential oil, efficiency and costs of the process. Extraction of essential oils from orange peels with MAD was better in terms of energy saving, extraction time (30 min versus 3 h), oxygenated fraction (11.7% versus 7.9%), product yield (0.42% versus 0.39%) and product quality. Orange peels treated by MAD and HD were observed by scanning electronic microscopy (SEM). Micrographs provide evidence of more rapid opening of essential oil glands treated by MAD, in contrast to conventional hydro-distillation.Keywords: clevenger, microwave, extraction; hydro-distillation, essential oil, orange peel
Procedia PDF Downloads 3422724 Investigation of Green Dye-Sensitized Solar Cells Based on Natural Dyes
Authors: M. Hosseinnezhad, K. Gharanjig
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Natural dyes, extracted from black carrot and bramble, were utilized as photosensitizers to prepare dye-sensitized solar cells (DSSCs). Spectrophotometric studies of the natural dyes in solution and on a titanium dioxide substrate were carried out in order to assess changes in the status of the dyes. The results show that the bathochromic shift is seen on the photo-electrode substrate. The chemical binding of the natural dyes at the surface photo-electrode were increased by the chelating effect of the Ti(IV) ions. The cyclic voltammetry results showed that all extracts are suitable to be performed in DSSCs. Finally, photochemical performance and stability of DSSCs based on natural dyes were studied. The DSSCs sensitized by black carrot extract have been reported to achieve up to Jsc=1.17 mAcm-2, Voc= 0.55 V, FF= 0.52, η=0.34%, whereas Bramble extract can obtain up to Jsc=2.24 mAcm-2, Voc= 0.54 V, FF= 0.57, η=0.71%. The power conversion efficiency was obtained from the mixed dyes in DSSCs. The power conversion efficiency of dye-sensitized solar cells using mixed Black carrot and Bramble dye is the average of the their efficiency in single DSSCs.Keywords: anthocyanin, dye-sensitized solar cells, green energy, optical materials
Procedia PDF Downloads 2352723 CFD Simulation of the Inlet Pressure Effects on the Cooling Capacity Enhancement for Vortex Tube with Couple Vortex Chambers
Authors: Nader Pourmahmoud, Amir Hassanzadeh
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This article investigates the effects of inlet pressure in a newly introduced vortex tube which has been equipped with an additional vortex chamber. A 3-D compressible turbulent flow computation has been carried out toward analysis of complex flow field in this apparatus. Numerical results of flows are derived by utilizing the standard k-ε turbulence model for analyzing high rotating complex flow field. The present research has focused on cooling effect and given a characteristics curve for minimum cool temperature. In addition, the effect of inlet pressure for both chambers has been studied in details. To be presented numerical results show that the effect of inlet pressure in second chamber has more important role in improving the performance of the vortex tube than first one. By increasing the pressure in the second chamber, cold outlet temperature reaches a higher decrease. When both chambers are fed with high pressure fluid, best operation condition of vortex tube occurs. However, it is not possible to feed both chambers with high pressure due to the conditions of working environment.Keywords: energy separation, inlet pressure, numerical simulation, vortex chamber, vortex tube
Procedia PDF Downloads 3612722 Characterization of Electrospun Carbon Nanofiber Doped Polymer Composites
Authors: Atilla Evcin, Bahri Ersoy, Süleyman Akpınar, I. Sinan Atlı
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Ceramic, polymer and composite nanofibers are nowadays begun to be utilized in many fields of nanotechnology. By the means of dimensions, these fibers are as small as nano scale but because of having large surface area and microstructural characteristics, they provide unique mechanic, optical, magnetic, electronic and chemical properties. In terms of nanofiber production, electrospinning has been the most widely used technique in recent years. In this study, carbon nanofibers have been synthesized from solutions of Polyacrylonitrile (PAN)/ N,N-dimethylformamide (DMF) by electrospinning method. The carbon nanofibers have been stabilized by oxidation at 250 °C for 2 h in air and carbonized at 750 °C for 1 h in H2/N2. Images of carbon nanofibers have been taken with scanning electron microscopy (SEM). The images have been analyzed to study the fiber morphology and to determine the distribution of the fiber diameter using FibraQuant 1.3 software. Then polymer composites have been produced from mixture of carbon nanofibers and silicone polymer. The final polymer composites have been characterized by X-ray diffraction method and scanning electron microscopy (SEM) energy dispersive X-ray (EDX) measurements. These results have been reported and discussed. At result, homogeneous carbon nanofibers with 100-167 nm of diameter were obtained with optimized electrospinning conditions.Keywords: electrospinning, characterization, composites, nanofiber
Procedia PDF Downloads 3862721 Study on Beta-Ray Detection System in Water Using a MCNP Simulation
Authors: Ki Hyun Park, Hye Min Park, Jeong Ho Kim, Chan Jong Park, Koan Sik Joo
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In the modern days, the use of radioactive substances is on the rise in the areas like chemical weaponry, industrial usage, and power plants. Although there are various technologies available to detect and monitor radioactive substances in the air, the technologies to detect underwater radioactive substances are scarce. In this study, computer simulation of the underwater detection system measuring beta-ray, a radioactive substance, has been done through MCNP. CaF₂, YAP(Ce) and YAG(Ce) have been used in the computer simulation to detect beta-ray as scintillator. Also, the source used in the computer simulation is Sr-90 and Y-90, both of them emitting only pure beta-ray. The distance between the source and the detector was shifted from 1mm to 10mm by 1 mm in the computer simulation. The result indicated that Sr-90 was impossible to measure below 1 mm since its emission energy is low while Y-90 was able to be measured up to 10mm underwater. In addition, the detector designed with CaF₂ had the highest efficiency among 3 scintillators used in the computer simulation. Since it was possible to verify the detectable range and the detection efficiency according to modeling through MCNP simulation, it is expected that such result will reduce the time and cost in building the actual beta-ray detector and evaluating its performances, thereby contributing the research and development.Keywords: Beta-ray, CaF₂, detector, MCNP simulation, scintillator
Procedia PDF Downloads 4952720 CFD Study on the Effect of Primary Air on Combustion of Simulated MSW Process in the Fixed Bed
Authors: Rui Sun, Tamer M. Ismail, Xiaohan Ren, M. Abd El-Salam
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Incineration of municipal solid waste (MSW) is one of the key scopes in the global clean energy strategy. A computational fluid dynamics (CFD) model was established. In order to reveal these features of the combustion process in a fixed porous bed of MSW. Transporting equations and process rate equations of the waste bed were modeled and set up to describe the incineration process, according to the local thermal conditions and waste property characters. Gas phase turbulence was modeled using k-ε turbulent model and the particle phase was modeled using the kinetic theory of granular flow. The heterogeneous reaction rates were determined using Arrhenius eddy dissipation and the Arrhenius-diffusion reaction rates. The effects of primary air flow rate and temperature in the burning process of simulated MSW are investigated experimentally and numerically. The simulation results in bed are accordant with experimental data well. The model provides detailed information on burning processes in the fixed bed, which is otherwise very difficult to obtain by conventional experimental techniques.Keywords: computational fluid dynamics (CFD) model, waste incineration, municipal solid waste (MSW), fixed bed, primary air
Procedia PDF Downloads 3932719 A Comparative Analysis of Green Buildings Rating Systems
Authors: Shadi Motamedighazvini, Roohollah Taherkhani, Mahdi Mahdikhani, Najme Hashempour
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Nowadays, green building rating systems are an inevitable necessity for managing environmental considerations to achieve green buildings. The aim of this paper is to deliver a detailed recognition of what has been the focus of green building policymakers around the world; It is important to conduct this study in a way that can provide a context for researchers who intend to establish or upgrade existing rating systems. In this paper, fifteen rating systems including four worldwide well-known plus eleven local rating systems which have been selected based on the answers to the questionnaires were examined. Their similarities and differences in mandatory and prerequisite clauses, highest and lowest scores for each criterion, the most frequent criteria, and most frequent sub-criteria are determined. The research findings indicated that although the criteria of energy, water, indoor quality (except Homestar), site and materials (except GRIHA) were common core criteria for all rating systems, their sub-criteria were different. This research, as a roadmap, eliminates the lack of a comprehensive reference that encompasses the key criteria of different rating systems. It shows the local systems need to be revised to be more comprehensive and adaptable to their own country’s conditions such as climate.Keywords: environmental assessment, green buildings, green building criteria, green building rating systems, sustainability, rating tools
Procedia PDF Downloads 2302718 Investigation of Steel-Concrete Composite Bridges under Blasting Loads Based on Slope Reflection
Authors: Yuan Li, Yitao Han, Zhao Zhu
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In this paper, the effect of blasting loads on steel-concrete composite bridges has been investigated considering the slope reflection effect. Reasonable values of girder size, plate thickness, stiffening rib, and other design parameters were selected according to design specifications. Modified RHT (Riedel-Hiermaier-Thoma) was used as constitutive relation in analyses. In order to simulate the slope reflection effect, the slope of the bridge was precisely built in the model. Different blasting conditions, including top, middle, and bottom explosions, were simulated. The multi-Euler domain method based on fully coupled Lagrange and Euler models was adopted for the structural analysis of the explosion process using commercial software AUTODYN. The obtained results showed that explosion overpressure was increased by 3006, 879, and 449kPa, corresponding to explosions occurring at the top, middle, and bottom of the slope, respectively. At the same time, due to energy accumulation and transmission dissipation caused by slope reflection, the corresponding yield lengths of steel beams were increased by 8, 0, and 5m, respectively.Keywords: steel-concrete composite bridge, explosion damage, slope reflection, blasting loads, RHT
Procedia PDF Downloads 882717 Compact Dual-Band Bandpass Filter Based on Quarter Wavelength Stepped Impedance Resonators
Authors: Yu-Fu Chen, Zih-Jyun Dai, Chen-Te Chiu, Shiue-Chen Chiou, Yung-Wei Chen, Yu-Ming Lin, Kuan-Yu Chen, Hung-Wei Wu, Hsin-Ying Lee, Yan-Kuin Su, Shoou-Jinn Chang
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This paper presents a compact dual-band bandpass filter that involves using the quarter wavelength stepped impedance resonators (SIRs) for achieving simultaneously compact circuit size and good dual-band performance. The filter is designed at 2.4 / 3.5 GHz and constructed by two pairs of quarter wavelength SIRs and source-load lines. By properly tuning the impedance ratio, length ratio and radius of via hole of the SIRs, dual-passbands performance can be easily determined. To improve the passband selectivity, the use of source-load lines is to increase coupling energy between the resonators. The filter is showing simple configuration, effective design method and small circuit size. The measured results are in good agreement with the simulation results.Keywords: dual-band, bandpass filter, stepped impedance resonators, SIR
Procedia PDF Downloads 5022716 Evaluation of Shock Sensitivity of Nano-Scaled 1,3,5-Trinitro-1,3,5-Triazacyclohexane Using Small Scale Gap Test
Authors: Kang-In Lee, Woo-Jin Lee, Keun-Deuk Lee, Ju-Seung Chae
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In this study, small scale gap test (SSGT) was performed to measure shock sensitivity of nano-scaled 1,3,5-trinitro-1,3,5-triazacyclohexane (RDX) samples. The shock sensitivity of energetic materials is usually evaluated by the method of large-scale gap test (LSGT) that has a higher reliability than other methods. But LSGT has the disadvantage that it takes a high cost and time by using a large amount of explosive. In this experiment, nano-scaled RDX samples were prepared by spray crystallization in two different drying methods. In addition, 30μm RDX sample produced by precipitation crystallization and 5μm RDX sample produced by fluid energy mill process were tested to compare shock sensitivity. The study of shock sensitivity measured by small-scale gap test shows that small sized RDX particles have greater insensitivity. As a result, we infer SSGT method has higher reliability compared to the literature as measurement of shock sensitivity of energetic materials.Keywords: nano-scaled RDX, SSGT(small scale gap test), shock sensitivity, RDX
Procedia PDF Downloads 2432715 Heat Transfer Coefficients of Layers of Greenhouse Thermal Screens
Authors: Vitaly Haslavsky, Helena Vitoshkin
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The total energy saving effect of different types of greenhouse thermal/shade screens was determined by measuring and calculating the overall heat transfer coefficients (U-values) for single and several layers of screens. The measurements were carried out using the hot box method, and the calculations were performed according to the ISO Standard 15099. The goal was to examine different types of materials with a wide range of thermal radiation properties used for thermal screens in combination with a dehumidification system in order to improve greenhouse insulation. The experimental results were in good agreement with the calculated heat transfer coefficients. It was shown that a high amount of infra-red (IR) radiation can be blocked by the greenhouse covering material in combination with moveable thermal screens. The aluminum foil screen could be replaced by transparent screens, depending on shading requirements. The results indicated that using a single layer, the U-value was reduced by approximately 70% compared to covering material alone, while the contributions of additional screen layers containing aluminum foil strips could reduce the U-value by approximately 90%. It was shown that three screen layers are sufficient for effective insulation.Keywords: greenhouse insulation, heat loss, thermal screens, U-value
Procedia PDF Downloads 1072714 An Analysis of Economical Drivers and Technical Challenges for Large-Scale Biohydrogen Deployment
Authors: Rouzbeh Jafari, Joe Nava
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This study includes learnings from an engineering practice normally performed on large scale biohydrogen processes. If properly scale-up is done, biohydrogen can be a reliable pathway for biowaste valorization. Most of the studies on biohydrogen process development have used model feedstock to investigate process key performance indicators (KPIs). This study does not intend to compare different technologies with model feedstock. However, it reports economic drivers and technical challenges which help in developing a road map for expanding biohydrogen economy deployment in Canada. BBA is a consulting firm responsible for the design of hydrogen production projects. Through executing these projects, activity has been performed to identify, register and mitigate technical drawbacks of large-scale hydrogen production. Those learnings, in this study, have been applied to the biohydrogen process. Through data collected by a comprehensive literature review, a base case has been considered as a reference, and several case studies have been performed. Critical parameters of the process were identified and through common engineering practice (process design, simulation, cost estimate, and life cycle assessment) impact of these parameters on the commercialization risk matrix and class 5 cost estimations were reported. The process considered in this study is food waste and woody biomass dark fermentation. To propose a reliable road map to develop a sustainable biohydrogen production process impact of critical parameters was studied on the end-to-end process. These parameters were 1) feedstock composition, 2) feedstock pre-treatment, 3) unit operation selection, and 4) multi-product concept. A couple of emerging technologies also were assessed such as photo-fermentation, integrated dark fermentation, and using ultrasound and microwave to break-down feedstock`s complex matrix and increase overall hydrogen yield. To properly report the impact of each parameter KPIs were identified as 1) Hydrogen yield, 2) energy consumption, 3) secondary waste generated, 4) CO2 footprint, 5) Product profile, 6) $/kg-H2 and 5) environmental impact. The feedstock is the main parameter defining the economic viability of biohydrogen production. Through parametric studies, it was found that biohydrogen production favors feedstock with higher carbohydrates. The feedstock composition was varied, by increasing one critical element (such as carbohydrate) and monitoring KPIs evolution. Different cases were studied with diverse feedstock, such as energy crops, wastewater slug, and lignocellulosic waste. The base case process was applied to have reference KPIs values and modifications such as pretreatment and feedstock mix-and-match were implemented to investigate KPIs changes. The complexity of the feedstock is the main bottleneck in the successful commercial deployment of the biohydrogen process as a reliable pathway for waste valorization. Hydrogen yield, reaction kinetics, and performance of key unit operations highly impacted as feedstock composition fluctuates during the lifetime of the process or from one case to another. In this case, concept of multi-product becomes more reliable. In this concept, the process is not designed to produce only one target product such as biohydrogen but will have two or multiple products (biohydrogen and biomethane or biochemicals). This new approach is being investigated by the BBA team and the results will be shared in another scientific contribution.Keywords: biohydrogen, process scale-up, economic evaluation, commercialization uncertainties, hydrogen economy
Procedia PDF Downloads 982713 Studies on Affecting Factors of Wheel Slip and Odometry Error on Real-Time of Wheeled Mobile Robots: A Review
Authors: D. Vidhyaprakash, A. Elango
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In real-time applications, wheeled mobile robots are increasingly used and operated in extreme and diverse conditions traversing challenging surfaces such as a pitted, uneven terrain, natural flat, smooth terrain, as well as wet and dry surfaces. In order to accomplish such tasks, it is critical that the motion control functions without wheel slip and odometry error during the navigation of the two-wheeled mobile robot (WMR). Wheel slip and odometry error are disrupting factors on overall WMR performance in the form of deviation from desired trajectory, navigation, travel time and budgeted energy consumption. The wheeled mobile robot’s ability to operate at peak performance on various work surfaces without wheel slippage and odometry error is directly connected to four main parameters, which are the range of payload distribution, speed, wheel diameter, and wheel width. This paper analyses the effects of those parameters on overall performance and is concerned with determining the ideal range of parameters for optimum performance.Keywords: wheeled mobile robot, terrain, wheel slippage, odometryerror, trajectory
Procedia PDF Downloads 2742712 Review of K0-Factors and Related Nuclear Data of the Selected Radionuclides for Use in K0-NAA
Authors: Manh-Dung Ho, Van-Giap Pham, Van-Doanh Ho, Quang-Thien Tran, Tuan-Anh Tran
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The k0-factors and related nuclear data, i.e. the Q0-factors and effective resonance energies (Ēr) of the selected radionuclides which are used in the k0-based neutron activation analysis (k0-NAA), were critically reviewed to be integrated in the “k0-DALAT” software. The k0- and Q0-factors of some short-lived radionuclides: 46mSc, 110Ag, 116m2In, 165mDy, and 183mW, were experimentally determined at the Dalat research reactor. The other radionuclides selected are: 20F, 36S, 49Ca, 60mCo, 60Co, 75Se, 77mSe, 86mRb, 115Cd, 115mIn, 131Ba, 134mCs, 134Cs, 153Gd, 153Sm, 159Gd, 170Tm, 177mYb, 192Ir, 197mHg, 239U and 239Np. The reviewed data as compared with the literature data were biased within 5.6-7.3% in which the experimental re-determined factors were within 6.1 and 7.3%. The NIST standard reference materials: Oyster Tissue (1566b), Montana II Soil (2711a) and Coal Fly Ash (1633b) were used to validate the new reviewed data showing that the new data gave an improved k0-NAA using the “k0-DALAT” software with a factor of 4.5-6.8% for the investigated radionuclides.Keywords: neutron activation analysis, k0-based method, k0 factor, Q0 factor, effective resonance energy
Procedia PDF Downloads 1152711 Solar-Electric Pump-out Boat Technology: Impacts on the Marine Environment, Public Health, and Climate Change
Authors: Joy Chiu, Colin Hemez, Emma Ryan, Jia Sun, Robert Dubrow, Michael Pascucilla
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The popularity of recreational boating is on the rise in the United States, which raises numerous national-level challenges in the management of air and water pollution, aquatic habitat destruction, and waterway access. The need to control sewage discharge from recreational vessels underlies all of these challenges. The release of raw human waste into aquatic environments can lead to eutrophication and algal blooms; can increase human exposure to pathogenic viruses, bacteria, and parasites; can financially impact commercial shellfish harvest/fisheries and marine bathing areas; and can negatively affect access to recreational and/or commercial waterways to the detriment of local economies. Because of the damage that unregulated sewage discharge can do to environments and human health/marine life, recreational vessels in the United States are required by law to 'pump-out' sewage from their holding tanks into sewage treatment systems in all designated 'no discharge areas'. Many pump-out boats, which transfer waste out of recreational vessels, are operated and maintained using funds allocated through the Federal Clean Vessel Act (CVA). The East Shore District Health Department of Branford, Connecticut is protecting this estuary by pioneering the design and construction of the first-in-the-nation zero-emissions, the solar-electric pump-out boat of its size to replace one of its older traditional gasoline-powered models through a Connecticut Department of Energy and Environmental Protection CVA Grant. This study, conducted in collaboration with the East Shore District Health Department, the Connecticut Department of Energy and Environmental Protection, States Organization for Boating Access and Connecticut’s CVA program coordinators, had two aims: (1) To perform a national assessment of pump-out boat programs, supplemented by a limited international assessment, to establish best pump-out boat practices (regardless of how the boat is powered); and (2) to estimate the cost, greenhouse gas emissions, and environmental and public health impacts of solar-electric versus traditional gasoline-powered pump-out boats. A national survey was conducted of all CVA-funded pump-out program managers and selected pump-out boat operators to gauge best practices; costs associated with gasoline-powered pump-out boat operation and management; and the regional, cultural, and policy-related issues that might arise from the adoption of solar-electric pump-out boat technology. We also conducted life-cycle analyses of gasoline-powered and solar-electric pump-out boats to compare their greenhouse gas emissions; production of air, soil and water pollution; and impacts on human health. This work comprises the most comprehensive study into pump-out boating practices in the United States to date, in which information obtained at local, state, national, and international levels is synthesized. This study aims to enable CVA programs to make informed recommendations for sustainable pump-out boating practices and identifies the challenges and opportunities that remain for the wide adoption of solar-electric pump-out boat technology.Keywords: pump-out boat, marine water, solar-electric, zero emissions
Procedia PDF Downloads 1202710 The Role of University in High-Level Human Capital Cultivation in China’s West Greater Bay Area
Authors: Rochelle Yun Ge
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University has played an active role in the country’s development in China. There has been an increasing research interest on the development of higher education cooperation, talent cultivation and attraction, and innovation in the regional development. The Triple Helix model, which indicates that regional innovation and development can be engendered by collaboration among university, industry and government, is often adopted as research framework. The research using triple helix model emphasizes the active and often leading role of university in knowledge-based economy. Within this framework, universities are conceptualized as key institutions of knowledge production, transmission and transference potentially making critical contributions to regional development. Recent research almost uniformly consistent in indicating the high-level research labours (i.e., doctoral, post-doctoral researchers and academics) as important actors in the innovation ecosystem with their cross-geographical human capital and resources presented. In 2019, the development of the Guangdong-Hong Kong-Macao Greater Bay Area (GBA) was officially launched as an important strategy by the Chinese government to boost the regional development of the Pearl River Delta and to support the realization of “One Belt One Road” strategy. Human Capital formation is at the center of this plan. One of the strategic goals of the GBA development is set to evolve into an international educational hub and innovation center with high-level talents. A number of policies have been issued to attract and cultivate human resources in different GBA cities, in particular for the high-level R&D (research and development) talents such as doctoral and post-doctoral researchers. To better understand the development of high-level talents hub in the GBA, more empirical considerations should be given to explore the approaches of talents cultivation and attraction in the GBA. What remains to explore is the ways to better attract, train, support and retain these talents in the cross-systems context. This paper aims to investigate the role of university in human capital development under China’s national agenda of GBA integration through the lens of universities and actors. Two flagship comprehensive universities are selected to be the cases and 30 interviews with university officials, research leaders, post-doctors and doctoral candidates are used for analysis. In particular, we look at in what ways have universities aligned their strategies and practices to the Chinese government’s GBA development strategy? What strategies and practices have been developed by universities for the cultivation and attraction of high-level research labor? And what impacts the universities have made for the regional development? The main arguments of this research highlights the specific ways in which universities in smaller sub-regions can collaborate in high-level human capital formation and the role policy can play in facilitating such collaborations.Keywords: university, human capital, regional development, triple-helix model
Procedia PDF Downloads 1012709 A Numerical Investigation of Flow Maldistribution in Inlet Header Configuration of Plate Fin Heat Exchanger
Authors: Appasaheb Raul
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Numerical analysis of a plate fin heat exchanger accounting for the effect of fluid flow maldistribution on the inlet header configuration of the heat exchanger is investigated. It is found that the flow maldistribution is very significant in normal to the flow direction. Various inlet configuration has been studied for various Reynolds Number. By the study, a modified header configuration is proposed and simulated. The two-dimensional parameters are used to evaluate the flow non-uniformity in the header, global flow maldistribution parameter (Sg), and Velocity Ratio (θ). A series of velocity vectors and streamline graphs at different cross-section are achieved and studied qualitatively with experimental results in the literature. The numerical result indicates that the flow maldistribution is serious in the conventional header while in the improved configuration less maldistribution occurs. The flow maldistribution parameter (Sg) and velocity ratio (θ) is reduced in improved configuration. The vortex decreases compared to that of the conventional configuration so the energy and pressure loss is reduced. The improved header can effectively enhance the efficiency of plate fin heat exchanger and uniformity of flow distribution.Keywords: global flow maldistribution parameter, Sg, velocity ratio, plate fin heat exchanger, fluent 14.5
Procedia PDF Downloads 5102708 Design of Cartesian Robot for Electric Vehicle Wireless Charging Systems
Authors: Kaan Karaoglu, Raif Bayir
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In this study, a cartesian robot is developed to improve the performance and efficiency of wireless charging of electric vehicles. The cartesian robot has three axes, each of which moves linearly. Magnetic positioning is used to align the cartesian robot transmitter charging pad. There are two different wireless charging methods, static and dynamic, for charging electric vehicles. The current state of charge information (SOC State of Charge) and location information are received wirelessly from the electric vehicle. Based on this information, the power to be transmitted is determined, and the transmitter and receiver charging pads are aligned for maximum efficiency. With this study, a fully automated cartesian robot structure will be used to charge electric vehicles with the highest possible efficiency. With the wireless communication established between the electric vehicle and the charging station, the charging status will be monitored in real-time. The cartesian robot developed in this study is a fully automatic system that can be easily used in static wireless charging systems with vehicle-machine communication.Keywords: electric vehicle, wireless charging systems, energy efficiency, cartesian robot, location detection, trajectory planning
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