Search results for: mechanical efficiency
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 9779

Search results for: mechanical efficiency

5639 The New Propensity Score Method and Assessment of Propensity Score: A Simulation Study

Authors: Azam Najafkouchak, David Todem, Dorothy Pathak, Pramod Pathak, Joseph Gardiner

Abstract:

Propensity score (PS) methods have recently become the standard analysis tool for causal inference in observational studies where exposure is not randomly assigned. Thus, confounding can impact the estimation of treatment effect on the outcome. Due to the dangers of discretizing continuous variables, the focus of this paper will be on how the variation in cut-points or boundaries will affect the average treatment effect utilizing the stratification of the PS method. In this study, we will develop a new methodology to improve the efficiency of the PS analysis through stratification and simulation study. We will also explore the property of empirical distribution of average treatment effect theoretically, including asymptotic distribution, variance estimation and 95% confident Intervals.

Keywords: propensity score, stratification, emprical distribution, average treatment effect

Procedia PDF Downloads 91
5638 A Novel Comparison Scheme for Thermal Conductivity Enhancement of Heat Transfer

Authors: Islam Tarek, Moataz Soliman

Abstract:

With the amazing development of nanoscience’s and the discovery of the unique properties of nanometric materials, the ideas of scientists and researchers headed to take advantage of this progress in various fields, and one of the most important of these areas is the field of heat transfer and benefit from it in saving energy used for heat transfer, so nanometric materials were used to improve the properties of heat transfer fluids and increase the efficiency of the liquid. In this paper, we will compare two types of heat transfer fluid, one industrial type (the base fluid is a mix of ethylene glycol and deionized water ) and another natural oils(the base fluid is a mix of jatropha oil and expired olive oil), explaining the method of preparing each of them, starting from the method of preparing CNT, collecting and sorting jatropha seeds, and the most appropriate method for extracting oil from them, and characterization the both of two fluids and when to use both.

Keywords: nanoscience, heat transfer, thermal conductivity, jatropha oil

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5637 Cost of Outpatient Procedures for Ostomized Patients Treated in the Public Health Network in Brazil and Its Impact on the Budget of the Unified Health System

Authors: Karina Guimaraes, Lilian Santos

Abstract:

This study has the purpose of planning and instituting monitoring actions as a way of knowing the scenario of assistance to the patient with stoma, treated in the public health network in Brazil, from January to November of the year 2016, from the elaboration of a technical document containing the survey of the number of procedures offered and the value of the ostomy services, accredited in the Unified Health System-SUS. The purpose of this document is to improve the quality of these services in the efficient management of available financial resources, making it indispensable for the creation of strategies for the implementation and implementation of care services for people with stomata as a strategic tool in the promotion, prevention, qualification and efficiency in health care.

Keywords: health economic, management, ostomy, unified health system

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5636 Starting Characteristic Analysis of LSPM for Pumping System Considering Demagnetization

Authors: Subrato Saha, Yun-Hyun Cho

Abstract:

This paper presents the design process of a high performance 3-phase 3.7 kW 2-pole line start permanent magnet synchronous motor for pumping system. A method was proposed to study the starting torque characteristics considering line start with high inertia load. A d-q model including cage was built to study the synchronization capability. Time-stepping finite element method analysis was utilized to accurately predict the dynamic and transient performance, efficiency, starting current, speed curve and, etc. Considering the load torque of pumps during starting stage, the rotor bar was designed with minimum demagnetization of permanent magnet caused by huge starting current.

Keywords: LSPM, starting analysis, demagnetization, FEA, pumping system

Procedia PDF Downloads 464
5635 Estimation of Scour Using a Coupled Computational Fluid Dynamics and Discrete Element Model

Authors: Zeinab Yazdanfar, Dilan Robert, Daniel Lester, S. Setunge

Abstract:

Scour has been identified as the most common threat to bridge stability worldwide. Traditionally, scour around bridge piers is calculated using the empirical approaches that have considerable limitations and are difficult to generalize. The multi-physic nature of scouring which involves turbulent flow, soil mechanics and solid-fluid interactions cannot be captured by simple empirical equations developed based on limited laboratory data. These limitations can be overcome by direct numerical modeling of coupled hydro-mechanical scour process that provides a robust prediction of bridge scour and valuable insights into the scour process. Several numerical models have been proposed in the literature for bridge scour estimation including Eulerian flow models and coupled Euler-Lagrange models incorporating an empirical sediment transport description. However, the contact forces between particles and the flow-particle interaction haven’t been taken into consideration. Incorporating collisional and frictional forces between soil particles as well as the effect of flow-driven forces on particles will facilitate accurate modeling of the complex nature of scour. In this study, a coupled Computational Fluid Dynamics and Discrete Element Model (CFD-DEM) has been developed to simulate the scour process that directly models the hydro-mechanical interactions between the sediment particles and the flowing water. This approach obviates the need for an empirical description as the fundamental fluid-particle, and particle-particle interactions are fully resolved. The sediment bed is simulated as a dense pack of particles and the frictional and collisional forces between particles are calculated, whilst the turbulent fluid flow is modeled using a Reynolds Averaged Navier Stocks (RANS) approach. The CFD-DEM model is validated against experimental data in order to assess the reliability of the CFD-DEM model. The modeling results reveal the criticality of particle impact on the assessment of scour depth which, to the authors’ best knowledge, hasn’t been considered in previous studies. The results of this study open new perspectives to the scour depth and time assessment which is the key to manage the failure risk of bridge infrastructures.

Keywords: bridge scour, discrete element method, CFD-DEM model, multi-phase model

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5634 Robust Speed Sensorless Control to Estimated Error for PMa-SynRM

Authors: Kyoung-Jin Joo, In-Gun Kim, Hyun-Seok Hong, Dong-Woo Kang, Ju Lee

Abstract:

Recently, the permanent magnet-assisted synchronous reluctance motor (PMa-SynRM) that can be substituted for the induction motor has been studying because of the needs of the development of the premium high efficiency motor for the minimum energy performance standard (MEPS). PMa-SynRM is required to the speed and position information for motor speed and torque controls. However, to apply the sensors has many problems that are sensor mounting space shortage and additional cost, etc. Therefore, in this paper, speed-sensorless control based on model reference adaptive system (MRAS) is introduced to eliminate the sensor. The sensorless method is constructed in a reference model as standard and an adaptive model as the state observer. The proposed algorithm is verified by the simulation.

Keywords: PMa-SynRM, sensorless control, robust estimation, MRAS method

Procedia PDF Downloads 390
5633 Design of a Universal Wireless Battery Charger

Authors: Ahmad B. Musamih, Ahmad A. Albloushi, Ahmed H. Alshemeili, Abdulaziz Y. Alfili, Ala A. Hussien

Abstract:

This paper proposes a universal wireless battery charger design for portable electronic devices. As the number of portable electronics devices increases, the demand for more flexible and reliable charging techniques is becoming more urgent. A wireless battery charger differs from a traditional charger in the way the power transferred to the battery. In the latter, the power is transferred through electrical wires that connect the charger terminals to the battery terminals, while in the former; the power is transferred by induction without electrical connections. With a detection algorithm that detects the battery size and chemistry, the proposed charger will be able to accommodate a wide range of applications, and will allow a more flexible and reliable option to most of today’s portable electronics.

Keywords: efficiency, magnetically-coupled resonators, resonance frequency, wireless power transfer

Procedia PDF Downloads 444
5632 Optimized Cluster Head Selection Algorithm Based on LEACH Protocol for Wireless Sensor Networks

Authors: Wided Abidi, Tahar Ezzedine

Abstract:

Low-Energy Adaptive Clustering Hierarchy (LEACH) has been considered as one of the effective hierarchical routing algorithms that optimize energy and prolong the lifetime of network. Since the selection of Cluster Head (CH) in LEACH is carried out randomly, in this paper, we propose an approach of electing CH based on LEACH protocol. In other words, we present a formula for calculating the threshold responsible for CH election. In fact, we adopt three principle criteria: the remaining energy of node, the number of neighbors within cluster range and the distance between node and CH. Simulation results show that our proposed approach beats LEACH protocol in regards of prolonging the lifetime of network and saving residual energy.

Keywords: wireless sensors networks, LEACH protocol, cluster head election, energy efficiency

Procedia PDF Downloads 324
5631 Effect of Multi-Walled Carbon Nanotubes on Fuel Cell Membrane Performance

Authors: Rabindranath Jana, Biswajit Maity, Keka Rana

Abstract:

The most promising clean energy source is the fuel cell, since it does not generate toxic gases and other hazardous compounds. Again the direct methanol fuel cell (DMFC) is more user-friendly as it is easy to be miniaturized and suited as energy source for automobiles as well as domestic applications and portable devices. And unlike the hydrogen used for some fuel cells, methanol is a liquid that is easy to store and transport in conventional tanks. The most important part of a fuel cell is its membrane. Till now, an overall efficiency for a methanol fuel cell is reported to be about 20 ~ 25%. The lower efficiency of the cell may be due to the critical factors, e.g. slow reaction kinetics at the anode and methanol crossover. The oxidation of methanol is composed of a series of successive reactions creating formaldehyde and formic acid as intermediates that contribute to slow reaction rates and decreased cell voltage. Currently, the investigation of new anode catalysts to improve oxidation reaction rates is an active area of research as it applies to the methanol fuel cell. Surprisingly, there are very limited reports on nanostructured membranes, which are rather simple to manufacture with different tuneable compositions and are expected to allow only the proton permeation but not the methanol due to their molecular sizing effects and affinity to the membrane surface. We have developed a nanostructured fuel cell membrane from polydimethyl siloxane rubber (PDMS), ethylene methyl co-acrylate (EMA) and multi-walled carbon nanotubes (MWNTs). The effect of incorporating different proportions of f-MWNTs in polymer membrane has been studied. The introduction of f-MWNTs in polymer matrix modified the polymer structure, and therefore the properties of the device. The proton conductivity, measured by an AC impedance technique using open-frame and two-electrode cell and methanol permeability of the membranes was found to be dependent on the f-MWNTs loading. The proton conductivity of the membranes increases with increase in concentration of f-MWNTs concentration due to increased content of conductive materials. Measured methanol permeabilities at 60oC were found to be dependant on loading of f-MWNTs. The methanol permeability decreased from 1.5 x 10-6 cm²/s for pure film to 0.8 x 10-7 cm²/s for a membrane containing 0.5wt % f-MWNTs. This is due to increasing proportion of f-MWNTs, the matrix becomes more compact. From DSC melting curves it is clear that the polymer matrix with f-MWNTs is thermally stable. FT-IR studies show good interaction between EMA and f-MWNTs. XRD analysis shows good crystalline behavior of the prepared membranes. Significant cost savings can be achieved when using the blended films which contain less expensive polymers.

Keywords: fuel cell membrane, polydimethyl siloxane rubber, carbon nanotubes, proton conductivity, methanol permeability

Procedia PDF Downloads 408
5630 Demonstration of Powering up Low Power Wireless Sensor Network by RF Energy Harvesting System

Authors: Lim Teck Beng, Thiha Kyaw, Poh Boon Kiat, Lee Ngai Meng

Abstract:

This work presents discussion on the possibility of merging two emerging technologies in microwave; wireless power transfer (WPT) and RF energy harvesting. The current state of art of the two technologies is discussed and the strength and weakness of the two technologies is also presented. The equivalent circuit of wireless power transfer is modeled and explained as how the range and efficiency can be further increased by controlling certain parameters in the receiver. The different techniques of harvesting the RF energy from the ambient are also extensive study. Last but not least, we demonstrate that a low power wireless sensor network (WSN) can be power up by RF energy harvesting. The WSN is designed to transmit every 3 minutes of information containing the temperature of the environment and also the voltage of the node. One thing worth mention is both the sensors that are used for measurement are also powering up by the RF energy harvesting system.

Keywords: energy harvesting, wireless power transfer, wireless sensor network and magnetic coupled resonator

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5629 Profitability and Productivity Performance of the Selected Public Sector Banks in India

Authors: Sudipto Jana

Abstract:

Background and significance of the study: Banking industry performs as a catalyst for industrial growth and agricultural growth, however, as well involves the existence and welfare of the citizens. The banking system in India was described by unmatched growth and the recreation of bunch making in the pre-liberalization era. At the time of financial sector reforms Reserve Bank of India issued a regulatory norm concerning capital adequacy, income recognition, asset classification and provisioning that have increasingly precede meeting by means of the international paramount performs. Bank management ceaselessly manages the triumph, effectiveness, productivity and performance of the bank as good performance, high productivity and efficiency authorizes the triumph of the bank management targets as well as aims of bank. In a comparable move toward performance of any economy depends upon the expediency and effectiveness of its financial system of nation establishes its economic growth indicators. Profitability and productivity are the most important relevant parameters of any banking group. Keeping in view of this, this study examines the profitability and productivity performance of the selected public sector banks in India. Methodology: This study is based on secondary data obtained from Reserve Bank of India database for the periods between 2006 and 2015. This study purposively selects four types of commercial banks, namely, State Bank of India, United Bank of India, Punjab National Bank and Allahabad Bank. In order to analyze the performance with relation to profitability and productivity, productivity performance indicators in terms of capital adequacy ratio, burden ratio, business per employee, spread per employee and advances per employee and profitability performance indicators in terms of return on assets, return on equity, return on advances and return on branch have been considered. In the course of analysis, descriptive statistics, correlation statistics and multiple regression have been used. Major findings: Descriptive statistics indicate that productivity performance of State Bank of India is very satisfactory than other public sector banks in India. But management of productivity is unsatisfactory in case of all the public sector banks under study. Correlation statistics point out that profitability of the public sector banks are strongly positively related with productivity performance in case of all the public sector banks under study. Multiple regression test results show that when profitability increases profit per employee increases and net non-performing assets decreases. Concluding statements: Productivity and profitability performance of United Bank of India, Allahabad Bank and Punjab National Bank are unsatisfactory due to poor management of asset quality as well as management efficiency. It needs government’s interference so that profitability and productivity performance are increased in the near future.

Keywords: India, productivity, profitability, public sector banks

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5628 Adsorption of Congo Red on MgO Nanoparticles Prepared by Molten Salt Method

Authors: Shahbaa F. Bdewi, Bakhtyar K. Aziz, Ayad A. R. Mutar

Abstract:

Nano-materials show different surface properties due to their high surface area and active sites. This study investigates the feasibility of using nano-MgO (NMO) for removing Congo red (CR) dye from wastewater. NMO was prepared by molten salt method. Equilibrium experiments show the equilibrium was reached after 120 minutes and maximum adsorption efficiency was obtained in acidic media up to pH 6. Isotherm studies revealed the favorability of the adsorption process. The overall adsorption process was spontaneous and endothermic in nature with a maximum adsorption capacity of 1100 mg g-1 at 40°C as estimated from Langmuir isotherm. The adsorption kinetics was found to follow pseudo second-order rate equation. Relatively high activation energy (180.7 kJ mol-1) was obtained which is consistent with chemisorption mechanism for the adsorption process.

Keywords: adsorption, congo red, magnesium oxide, nanoparticles

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5627 Design Optimization of the Primary Containment Building of a Pressurized Water Reactor

Authors: M. Hossain, A. H. Khan, M. A. R. Sarkar

Abstract:

Primary containment structure is one of the five safety layers of a nuclear facility which is needed to be designed in such a manner that it can withstand the pressure and excessive radioactivity during accidental situations. It is also necessary to ensure minimization of cost with maximum possible safety in order to make the design economically feasible and attractive. This paper attempts to identify the optimum design conditions for primary containment structure considering both mechanical and radiation safety keeping the economic aspects in mind. This work takes advantage of commercial simulation software to identify the suitable conditions without the requirement of costly experiments. Generated data may be helpful for further studies.

Keywords: PWR, concrete containment, finite element approach, neutron attenuation, Von Mises stress

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5626 Review of Energy Efficiency Routing in Ad Hoc Wireless Networks

Authors: P. R. Dushantha Chaminda, Peng Kai

Abstract:

In this review paper, we enclose the thought of wireless ad hoc networks and particularly mobile ad hoc network (MANET), their field of study, intention, concern, benefit and disadvantages, modifications, with relation of AODV routing protocol. Mobile computing is developing speedily with progression in wireless communications and wireless networking protocols. Making communication easy, we function most wireless network devices and sensor networks, movable, battery-powered, thus control on a highly constrained energy budget. However, progress in battery technology presents that only little improvements in battery volume can be expected in the near future. Moreover, recharging or substitution batteries is costly or unworkable, it is preferable to support energy waste level of devices low.

Keywords: wireless ad hoc network, energy efficient routing protocols, AODV, EOAODV, AODVEA, AODVM, AOMDV, FF-AOMDV, AOMR-LM

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5625 Morphology Optimization and Photophysics Study in Air-Processed Perovskite Solar Cells

Authors: Soumitra Satapathi, Anubhav Raghav

Abstract:

Perovskite solar cell technology has passed through a phase of unprecedented growth in the efficiency scale from 3.8% to above 22% within a half decade. This technology has drawn tremendous research interest. It has been observed that performances of perovskite based solar cells are extremely dependent on the morphology and crystallinity of the perovskite layer. It has also been observed that device lifetime depends on the perovskite morphology; devices with larger perovskite grains degrade slowly than those of the smaller ones. Various methods of perovskite growth have been applied to achieve the most appropriate morphology necessary for high efficient solar cells. The recent progress in morphology optimization by various methods emphasizing on grain sizes, stoichiometry, and ambient compatibility as well as photophysics study in air-processed perovskite solar cells will be discussed.

Keywords: perovskite solar cells, morphology optimization, photophysics study, air-processed solar cells

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5624 Renewable Integration Algorithm to Compensate Photovoltaic Power Using Battery Energy Storage System

Authors: Hyung Joo Lee, Jin Young Choi, Gun Soo Park, Kyo Sun Oh, Dong Jun Won

Abstract:

The fluctuation of the output of the renewable generator caused by weather conditions must be mitigated because it imposes strain on the system and adversely affects power quality. In this paper, we focus on mitigating the output fluctuation of the photovoltaic (PV) using battery energy storage system (BESS). To satisfy tight conditions of system, proposed algorithm is developed. This algorithm focuses on adjusting the integrated output curve considering state of capacity (SOC) of the battery. In this paper, the simulation model is PSCAD / EMTDC software. SOC of the battery and the overall output curve are shown using the simulation results. We also considered losses and battery efficiency.

Keywords: photovoltaic generation, battery energy storage system, renewable integration, power smoothing

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5623 Sol-Gel Erbium-Doped Silica-Hafnia Planar Waveguides

Authors: Mustapha El Mataouy, Abellatif Aaliti, Mouhamed Khaddor

Abstract:

Erbium actived silica-hafnia planar waveguides have been prepared by sol-gel route. The films were deposited on vitreous silica substrates using dip-coating technique. The parameters of preparation have been chosen to optimize the waveguides for operation in the near infrared (NIR) region, and to increase the luminescence efficiency of the metastable 4I13/2 state of Erbium ions. The waveguides properties were determined by m-lines spectroscopy, loss measurements. Waveguide Raman and luminescence spectroscopy were used to obtain information about the structure of the prepared films and about the dynamical process related to the emission in the C telecom band (1530nm-1565nm) of the Erbium ions. The results are discussed with the aim of comparing the structural and optical properties of Erbium activated silica-hafnia planar waveguides with different molar ratio of Si / Hf.

Keywords: erbium, optical amplifiers, silica-hafnia, sol-gel, waveguide

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5622 Field Study for Evaluating Winter Thermal Performance of Auckland School Buildings

Authors: Bin Su

Abstract:

Auckland has a temperate climate with comfortable warm, dry summers and mild, wet winters. An Auckland school normally does not need air conditioning for cooling during the summer and only needs heating during the winter. The Auckland school building thermal design should more focus on winter thermal performance and indoor thermal comfort for energy efficiency. This field study of testing indoor and outdoor air temperatures, relative humidity and indoor surface temperatures of three classrooms with different envelopes were carried out in the Avondale College during the winter months in 2013. According to the field study data, this study is to compare and evaluate winter thermal performance and indoor thermal conditions of school buildings with different envelopes.

Keywords: building envelope, building mass effect, building thermal comfort, building thermal performance, school building

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5621 Energy Saving Techniques for MIMO Decoders

Authors: Zhuofan Cheng, Qiongda Hu, Mohammed El-Hajjar, Basel Halak

Abstract:

Multiple-input multiple-output (MIMO) systems can allow significantly higher data rates compared to single-antenna-aided systems. They are expected to be a prominent part of the 5G communication standard. However, these decoders suffer from high power consumption. This work presents a design technique in order to improve the energy efficiency of MIMO systems; this facilitates their use in the next generation of battery-operated communication devices such as mobile phones and tablets. The proposed optimization approach consists of the use of low complexity lattice reduction algorithm in combination with an adaptive VLSI implementation. The proposed design has been realized and verified in 65nm technology. The results show that the proposed design is significantly more energy-efficient than conventional K-best MIMO systems.

Keywords: energy, lattice reduction, MIMO, VLSI

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5620 The Effect of Air Entraining Agents on Compressive Strength

Authors: Demet Yavuz

Abstract:

Freeze-thaw cycles are one of the greatest threats to concrete durability. Lately, protection against this threat excites scientists’ attention. Air-entraining admixtures have been widely used to produce freeze-thaw resistant at concretes. The use of air-entraining agents (AEAs) enhances not only freeze-thaw endurance but also the properties of fresh concrete such as segregation, bleeding and flow ability. This paper examines the effects of air-entraining on compressive strength of concrete. Air-entraining is used between 0.05% and 0.4% by weight of cement. One control and four fiber reinforced concrete mixes are prepared and three specimens are tested for each mix. It is concluded from the test results that when air entraining is increased the compressive strength of concrete reduces for all mixes with AEAs.

Keywords: concrete, air-entraining, compressive strength, mechanical properties

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5619 Optimizing Resource Management in Cloud Computing through Blockchain-Enabled Cost Transparency

Authors: Raghava Satya SaiKrishna Dittakavi

Abstract:

Cloud computing has revolutionized how businesses and individuals store, access, and process data, increasing efficiency and reducing infrastructure costs. However, the need for more transparency in cloud service billing often raises concerns about overcharging and hidden fees, hindering the realization of the full potential of cloud computing. This research paper explores how blockchain technology can be leveraged to introduce cost transparency and accountability in cloud computing services. We present a comprehensive analysis of blockchain-enabled solutions that enhance cost visibility, facilitate auditability, and promote trust in cloud service providers. Through this study, we aim to provide insights into the potential benefits and challenges of implementing blockchain in the cloud computing domain, leading to improved cost management and customer satisfaction.

Keywords: blockchain, cloud computing, cost transparency, blockchain technology

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5618 Biogas Control: Methane Production Monitoring Using Arduino

Authors: W. Ait Ahmed, M. Aggour, M. Naciri

Abstract:

Extracting energy from biomass is an important alternative to produce different types of energy (heat, electricity, or both) assuring low pollution and better efficiency. It is a new yet reliable approach to reduce green gas emission by extracting methane from industry effluents and use it to power machinery. We focused in our project on using paper and mill effluents, treated in a UASB reactor. The methane produced is used in the factory’s power supply. The aim of this work is to develop an electronic system using Arduino platform connected to a gas sensor, to measure and display the curve of daily methane production on processing. The sensor will send the gas values in ppm to the Arduino board so that the later sends the RS232 hardware protocol. The code developed with processing will transform the values into a curve and display it on the computer screen.

Keywords: biogas, Arduino, processing, code, methane, gas sensor, program

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5617 Simulation of the Visco-Elasto-Plastic Deformation Behaviour of Short Glass Fibre Reinforced Polyphthalamides

Authors: V. Keim, J. Spachtholz, J. Hammer

Abstract:

The importance of fibre reinforced plastics continually increases due to the excellent mechanical properties, low material and manufacturing costs combined with significant weight reduction. Today, components are usually designed and calculated numerically by using finite element methods (FEM) to avoid expensive laboratory tests. These programs are based on material models including material specific deformation characteristics. In this research project, material models for short glass fibre reinforced plastics are presented to simulate the visco-elasto-plastic deformation behaviour. Prior to modelling specimens of the material EMS Grivory HTV-5H1, consisting of a Polyphthalamide matrix reinforced by 50wt.-% of short glass fibres, are characterized experimentally in terms of the highly time dependent deformation behaviour of the matrix material. To minimize the experimental effort, the cyclic deformation behaviour under tensile and compressive loading (R = −1) is characterized by isothermal complex low cycle fatigue (CLCF) tests. Combining cycles under two strain amplitudes and strain rates within three orders of magnitude and relaxation intervals into one experiment the visco-elastic deformation is characterized. To identify visco-plastic deformation monotonous tensile tests either displacement controlled or strain controlled (CERT) are compared. All relevant modelling parameters for this complex superposition of simultaneously varying mechanical loadings are quantified by these experiments. Subsequently, two different material models are compared with respect to their accuracy describing the visco-elasto-plastic deformation behaviour. First, based on Chaboche an extended 12 parameter model (EVP-KV2) is used to model cyclic visco-elasto-plasticity at two time scales. The parameters of the model including a total separation of elastic and plastic deformation are obtained by computational optimization using an evolutionary algorithm based on a fitness function called genetic algorithm. Second, the 12 parameter visco-elasto-plastic material model by Launay is used. In detail, the model contains a different type of a flow function based on the definition of the visco-plastic deformation as a part of the overall deformation. The accuracy of the models is verified by corresponding experimental LCF testing.

Keywords: complex low cycle fatigue, material modelling, short glass fibre reinforced polyphthalamides, visco-elasto-plastic deformation

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5616 Comparative Analysis of Simulation-Based and Mixed-Integer Linear Programming Approaches for Optimizing Building Modernization Pathways Towards Decarbonization

Authors: Nico Fuchs, Fabian Wüllhorst, Laura Maier, Dirk Müller

Abstract:

The decarbonization of building stocks necessitates the modernization of existing buildings. Key measures for this include reducing energy demands through insulation of the building envelope, replacing heat generators, and installing solar systems. Given limited financial resources, it is impractical to modernize all buildings in a portfolio simultaneously; instead, prioritization of buildings and modernization measures for a given planning horizon is essential. Optimization models for modernization pathways can assist portfolio managers in this prioritization. However, modeling and solving these large-scale optimization problems, often represented as mixed-integer problems (MIP), necessitates simplifying the operation of building energy systems particularly with respect to system dynamics and transient behavior. This raises the question of which level of simplification remains sufficient to accurately account for realistic costs and emissions of building energy systems, ensuring a fair comparison of different modernization measures. This study addresses this issue by comparing a two-stage simulation-based optimization approach with a single-stage mathematical optimization in a mixed-integer linear programming (MILP) formulation. The simulation-based approach serves as a benchmark for realistic energy system operation but requires a restriction of the solution space to discrete choices of modernization measures, such as the sizing of heating systems. After calculating the operation of different energy systems in terms of the resulting final energy demands in simulation models on a first stage, the results serve as input for a second stage MILP optimization, where the design of each building in the portfolio is optimized. In contrast to the simulation-based approach, the MILP-based approach can capture a broader variety of modernization measures due to the efficiency of MILP solvers but necessitates simplifying the building energy system operation. Both approaches are employed to determine the cost-optimal design and dimensioning of several buildings in a portfolio to meet climate targets within limited yearly budgets, resulting in a modernization pathway for the entire portfolio. The comparison reveals that the MILP formulation successfully captures design decisions of building energy systems, such as the selection of heating systems and the modernization of building envelopes. However, the results regarding the optimal dimensioning of heating technologies differ from the results of the two-stage simulation-based approach, as the MILP model tends to overestimate operational efficiency, highlighting the limitations of the MILP approach.

Keywords: building energy system optimization, model accuracy in optimization, modernization pathways, building stock decarbonization

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5615 SEM-EBSD Observation for Microtubes by Using Dieless Drawing Process

Authors: Takashi Sakai, Itaru Kumisawa

Abstract:

Because die drawing requires insertion of a die, a plug, or a mandrel, higher precision and efficiency are demanded for drawing equipment for a tube having smaller diameter. Manufacturing of such tubes is also accompanied by problems such as cracking and fracture. We specifically examine dieless drawing, which is less affected by these drawing-related difficulties. This deformation process is governed by a similar principle to that of reduction in diameter when pulling a heated glass tube. We conducted dieless drawing of SUS304 stainless steel microtubes under various conditions with three factor parameters of heating temperature, area reduction, and drawing speed. We used SEM-EBSD to observe the processing condition effects on microstructural elements. As the result of this study, crystallographic orientation of microtube is clear by using SEM-EBSD analysis.

Keywords: microtube, dieless drawing, IPF (inverse pole figure), GOS (grain orientation spread), crystallographic analysis

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5614 Estimation of Enantioresolution of Multiple Stereogenic Drugs Using Mobilized and/or Immobilized Polysaccharide-Based HPLC Chiral Stationary Phases

Authors: Mohamed Hefnawy, Abdulrahman Al-Majed, Aymen Al-Suwailem

Abstract:

Enantioseparation of drugs with multiple stereogenic centers is challenging. This study objectives to evaluate the efficiency of different mobilized and/or immobilized polysaccharide-based chiral stationary phases to separate enantiomers of some drugs containing multiple stereogenic centers namely indenolol, nadolol, labetalol. The critical mobile phase variables (composition of organic solvents, acid/base ratios) were carefully studied to compare the retention time and elution order of all isomers. Different chromatographic parameters such as capacity factor (k), selectivity (α) and resolution (Rs) were calculated. Experimental conditions and the possible chiral recognition mechanisms have been discussed.

Keywords: HPLC, polysaccharide columns, enantio-resolution, indenolol, nadolol, labetalol

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5613 Simulation Data Summarization Based on Spatial Histograms

Authors: Jing Zhao, Yoshiharu Ishikawa, Chuan Xiao, Kento Sugiura

Abstract:

In order to analyze large-scale scientific data, research on data exploration and visualization has gained popularity. In this paper, we focus on the exploration and visualization of scientific simulation data, and define a spatial V-Optimal histogram for data summarization. We propose histogram construction algorithms based on a general binary hierarchical partitioning as well as a more specific one, the l-grid partitioning. For effective data summarization and efficient data visualization in scientific data analysis, we propose an optimal algorithm as well as a heuristic algorithm for histogram construction. To verify the effectiveness and efficiency of the proposed methods, we conduct experiments on the massive evacuation simulation data.

Keywords: simulation data, data summarization, spatial histograms, exploration, visualization

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5612 Product Life Cycle Assessment of Generatively Designed Furniture for Interiors Using Robot Based Additive Manufacturing

Authors: Andrew Fox, Qingping Yang, Yuanhong Zhao, Tao Zhang

Abstract:

Furniture is a very significant subdivision of architecture and its inherent interior design activities. The furniture industry has developed from an artisan-driven craft industry, whose forerunners saw themselves manifested in their crafts and treasured a sense of pride in the creativity of their designs, these days largely reduced to an anonymous collective mass-produced output. Although a very conservative industry, there is great potential for the implementation of collaborative digital technologies allowing a reconfigured artisan experience to be reawakened in a new and exciting form. The furniture manufacturing industry, in general, has been slow to adopt new methodologies for a design using artificial and rule-based generative design. This tardiness has meant the loss of potential to enhance its capabilities in producing sustainable, flexible, and mass customizable ‘right first-time’ designs. This paper aims to demonstrate the concept methodology for the creation of alternative and inspiring aesthetic structures for robot-based additive manufacturing (RBAM). These technologies can enable the economic creation of previously unachievable structures, which traditionally would not have been commercially economic to manufacture. The integration of these technologies with the computing power of generative design provides the tools for practitioners to create concepts which are well beyond the insight of even the most accomplished traditional design teams. This paper aims to address the problem by introducing generative design methodologies employing the Autodesk Fusion 360 platform. Examination of the alternative methods for its use has the potential to significantly reduce the estimated 80% contribution to environmental impact at the initial design phase. Though predominantly a design methodology, generative design combined with RBAM has the potential to leverage many lean manufacturing and quality assurance benefits, enhancing the efficiency and agility of modern furniture manufacturing. Through a case study examination of a furniture artifact, the results will be compared to a traditionally designed and manufactured product employing the Ecochain Mobius product life cycle analysis (LCA) platform. This will highlight the benefits of both generative design and robot-based additive manufacturing from an environmental impact and manufacturing efficiency standpoint. These step changes in design methodology and environmental assessment have the potential to revolutionise the design to manufacturing workflow, giving momentum to the concept of conceiving a pre-industrial model of manufacturing, with the global demand for a circular economy and bespoke sustainable design at its heart.

Keywords: robot, manufacturing, generative design, sustainability, circular econonmy, product life cycle assessment, furniture

Procedia PDF Downloads 132
5611 An Integrated Tailoring Method for Thermal Cycling Tests of Spacecraft Electronics

Authors: Xin-Yan Ji, Jing Wang, Chang Liu, Yan-Qiang Bi, Zhong-Xu Xu, Xi-Yuan Li

Abstract:

Thermal tests of electronic units are critically important for the reliability validation and performance demonstration of the spacecraft hard-wares. The tailoring equation in MIL-STD-1540 is based on fatigue of solder date. In the present paper, a new test condition tailoring expression is proposed to fit different thermo-mechanical fatigue and different subsystems, by introducing an integrated evaluating method for the fatigue acceleration exponent. The validate test has been accomplished and the data has been analyzed and compared with that from the MIL-STD-1540 tailoring equations. The results are encouraging and reasonable.

Keywords: thermal cycling test, thermal fatigue, tailoring equation, test condition planning

Procedia PDF Downloads 443
5610 Cigarette Smoke Detection Based on YOLOV3

Authors: Wei Li, Tuo Yang

Abstract:

In order to satisfy the real-time and accurate requirements of cigarette smoke detection in complex scenes, a cigarette smoke detection technology based on the combination of deep learning and color features was proposed. Firstly, based on the color features of cigarette smoke, the suspicious cigarette smoke area in the image is extracted. Secondly, combined with the efficiency of cigarette smoke detection and the problem of network overfitting, a network model for cigarette smoke detection was designed according to YOLOV3 algorithm to reduce the false detection rate. The experimental results show that the method is feasible and effective, and the accuracy of cigarette smoke detection is up to 99.13%, which satisfies the requirements of real-time cigarette smoke detection in complex scenes.

Keywords: deep learning, computer vision, cigarette smoke detection, YOLOV3, color feature extraction

Procedia PDF Downloads 75