Search results for: Building stock energy modelling
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4480

Search results for: Building stock energy modelling

2260 A Tool for Modeling Slope Instability Triggered by Piping

Authors: Paola Gattinoni, Vincenzo Francani

Abstract:

The paper deals with the analysis of triggering conditions and evolution processes of piping phenomena, in relation to both mechanical and hydraulic aspects. In particular, the aim of the study is to predict slope instabilities triggered by piping, analysing the conditions necessary for a flow failure to occur. Really, the mechanical effect involved in the loads redistribution around the pipe is coupled to the drainage process arising from higher permeability of the pipe. If after the pipe formation, the drainage goes prevented for pipe clogging, the porewater pressure increase can lead to the failure or even the liquefaction, with a subsequent flow slide. To simulate the piping evolution and to verify relevant stability conditions, a iterative coupled modelling approach has been pointed out. As example, the proposed tool has been applied to the Stava Valley disaster (July, 1985), demonstrating that piping might be one of triggering phenomena of the tailings dams collapse.

Keywords: Flow failure, liquefaction, modeling, piping, porewater pressure.

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2259 Worm Gearing Design Improvement by Considering Varying Mesh Stiffness

Authors: A. H. Elkholy, A. H. Falah

Abstract:

A new approach has been developed to estimate the load share and distribution of worm gear drives, and to calculate the instantaneous tooth meshing stiffness. In the approach, the worm gear drive was modelled as a series of spur gear slices, and each slice was analyzed separately using the well-established formulae of spur gear loading and stresses. By combining the results obtained for all slices, the entire envolute worm gear set loading and stressing was obtained. The geometric modelling method presented allows tooth elastic deformation and tooth root stresses of worm gear drives under different load conditions to be investigated. Based on the slicing method introduced in this study, the instantaneous meshing stiffness and load share are obtained. In comparison with existing methods, this approach has both good analysis accuracy and less computing time.

Keywords: Gear, load/stress distribution, worm, wheel, tooth stiffness, contact line.

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2258 The Effect of the Deposition Parameters on the Microstructural and Optical Properties of Mn-Doped GeTe Chalcogenide Materials

Authors: Adam Abdalla Elbashir Adam, Xiaomin Cheng, Xiang Shui Miao

Abstract:

In this work, the effect of the magnetron sputtering system parameters on the optical properties of the Mn doped GeTe were investigated. The optical properties of the Ge1-xMnxTe thin films with different thicknesses are determined by analyzing the transmittance and reflectance data. The energy band gaps of the amorphous Mn-doped GeTe thin films with different thicknesses were calculated. The obtained results demonstrated that the energy band gap values of the amorphous films are quite different and they are dependent on the films thicknesses. The extinction coefficients of amorphous Mn-doped GeTe thin films as function of wavelength for different thicknesses were measured. The results showed that the extinction coefficients of all films are varying inversely with their optical transmission. Moreover, the results emphasis that, not only the microstructure, electrical and magnetic properties of Mn doped GeTe thin films vary with the films thicknesses but also the optical properties differ with the film thickness.

Keywords: Phase change magnetic materials, transmittance, absorbance, extinction coefficients.

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2257 Numerical Computation of Sturm-Liouville Problem with Robin Boundary Condition

Authors: Theddeus T. Akano, Omotayo A. Fakinlede

Abstract:

The modelling of physical phenomena, such as the earth’s free oscillations, the vibration of strings, the interaction of atomic particles, or the steady state flow in a bar give rise to Sturm- Liouville (SL) eigenvalue problems. The boundary applications of some systems like the convection-diffusion equation, electromagnetic and heat transfer problems requires the combination of Dirichlet and Neumann boundary conditions. Hence, the incorporation of Robin boundary condition in the analyses of Sturm-Liouville problem. This paper deals with the computation of the eigenvalues and eigenfunction of generalized Sturm-Liouville problems with Robin boundary condition using the finite element method. Numerical solution of classical Sturm–Liouville problem is presented. The results show an agreement with the exact solution. High results precision is achieved with higher number of elements.

Keywords: Sturm-Liouville problem, Robin boundary condition, finite element method, eigenvalue problems.

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2256 Economic and Environmental Benefits of the Best Available Technique Application in a Food Processing Plant

Authors: Frantisek Bozek, Pavel Budinsky, Ignac Hoza, Alexandr Bozek, Magdalena Naplavova

Abstract:

A cleaner production project was implemented in a bakery. The project is based on the substitution of the best available technique for an obsolete leaven production technology. The new technology enables production of durable, high-quality leavens. Moreover, 25% of flour as the original raw material can be replaced by pastry from the previous day production which has not been sold. That pastry was previously disposed in a waste incineration plant. Besides the environmental benefits resulting from less waste, lower consumption of energy, reduction of sewage waters quantity and floury dustiness there are also significant economic benefits. Payback period of investment was calculated with help of static method of financial analysis about 2.6 years, using dynamic method 3.5 years and an internal rate of return more than 29%. The supposed annual average profit after taxationin the second year of operation was incompliance with the real profit.

Keywords: Bakery, best available technology, cleaner production, costs, economic benefit, efficiency, energy, environmental benefit, investment, savings.

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2255 Produced Gas Conversion of Microwave Carbon Receptor Reforming

Authors: Young Nam Chun, Mun Sup Lim

Abstract:

Carbon dioxide and methane, the major components of biomass pyrolysis/gasification gas and biogas, top the list of substances that cause climate change, but they are also among the most important renewable energy sources in modern society. The purpose of this study is to convert carbon dioxide and methane into high-quality energy using char and commercial activated carbon obtained from biomass pyrolysis as a microwave receptor. The methane reforming process produces hydrogen and carbon. This carbon is deposited in the pores of the microwave receptor and lowers catalytic activity, thereby reducing the methane conversion rate. The deposited carbon was removed by carbon gasification due to the supply of carbon dioxide, which solved the problem of microwave receptor inactivity. In particular, the conversion rate remained stable at over 90% when the ratio of carbon dioxide to methane was 1:1. When the reforming results of carbon dioxide and methane were compared after fabricating nickel and iron catalysts using commercial activated carbon as a carrier, the conversion rate was higher in the iron catalyst than in the nickel catalyst and when no catalyst was used. 

Keywords: Microwave, gas reforming, greenhouse gas, microwave receptor, catalyst.

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2254 Modelling Medieval Vaults: Digital Simulation of the North Transept Vault of St Mary, Nantwich, England

Authors: N. Webb, A. Buchanan

Abstract:

Digital and virtual heritage is often associated with the recreation of lost artefacts and architecture; however, we can also investigate works that were not completed, using digital tools and techniques. Here we explore physical evidence of a fourteenth-century Gothic vault located in the north transept of St Mary’s church in Nantwich, Cheshire, using existing springer stones that are built into the walls as a starting point. Digital surveying tools are used to document the architecture, followed by an analysis process to hypothesise and simulate possible design solutions, had the vault been completed. A number of options, both two-dimensionally and three-dimensionally, are discussed based on comparison with examples of other contemporary vaults, thus adding another specimen to the corpus of vault designs. Dissemination methods such as digital models and 3D prints are also explored as possible resources for demonstrating what the finished vault might have looked like for heritage interpretation and other purposes.

Keywords: Digital simulation, heritage interpretation, medieval vaults, virtual heritage, 3D scanning.

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2253 Spatial Econometric Approaches for Count Data: An Overview and New Directions

Authors: Paula Simões, Isabel Natário

Abstract:

This paper reviews a number of theoretical aspects for implementing an explicit spatial perspective in econometrics for modelling non-continuous data, in general, and count data, in particular. It provides an overview of the several spatial econometric approaches that are available to model data that are collected with reference to location in space, from the classical spatial econometrics approaches to the recent developments on spatial econometrics to model count data, in a Bayesian hierarchical setting. Considerable attention is paid to the inferential framework, necessary for structural consistent spatial econometric count models, incorporating spatial lag autocorrelation, to the corresponding estimation and testing procedures for different assumptions, to the constrains and implications embedded in the various specifications in the literature. This review combines insights from the classical spatial econometrics literature as well as from hierarchical modeling and analysis of spatial data, in order to look for new possible directions on the processing of count data, in a spatial hierarchical Bayesian econometric context.

Keywords: Spatial data analysis, spatial econometrics, Bayesian hierarchical models, count data.

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2252 Nutritional Value Determination of Different Varieties of Oats and Barley Using Near-Infrared Spectroscopy Method for the Horses Nutrition

Authors: V. Viliene, V. Sasyte, A. Raceviciute-Stupeliene, R. Gruzauskas

Abstract:

In horse nutrition, the most suitable cereal for their rations composition could be defined as oats and barley. Oats have high nutritive value because it provides more protein, fiber, iron and zinc than other whole grains, has good taste, and an activity of stimulating metabolic changes in the body. Another cereal – barley is very similar to oats as a feed except for some characteristics that affect how it is used; however, barley is lower in fiber than oats and is classified as a "heavy" feed. The value of oats and barley grain, first of all is dependent on its composition. Near-infrared spectroscopy (NIRS) has long been considered and used as a significant method in component and quality analysis and as an emerging technology for authenticity applications for cereal quality control. This paper presents the chemical and amino acid composition of different varieties of barley and oats, also digestible energy of different cereals for horses. Ten different spring barley (n = 5) and oats (n = 5) varieties, grown in one location in Lithuania, were assayed for their chemical composition (dry matter, crude protein, crude fat, crude ash, crude fiber, starch) and amino acids content, digestible amino acids and amino acids digestibility. Also, the grains digestible energy for horses was calculated. The oats and barley samples reflectance spectra were measured by means of NIRS using Foss-Tecator DS2500 equipment. The chemical components: fat, crude protein, starch and fiber differed statistically (P<0.05) between the oats and barley varieties. The highest total amino acid content between oats was determined in variety Flamingsprofi (4.56 g/kg) and the lowest – variety Circle (3.57 g/kg), and between barley - respectively in varieties Publican (3.50 g/kg) and Sebastian (3.11 g/kg). The different varieties of oats digestible amino acid content varied from 3.11 g/kg to 4.07 g/kg; barley different varieties varied from 2.59 g/kg to 2.94 g/kg. The average amino acids digestibility of oats varied from 74.4% (Liz) to 95.6% (Fen) and in barley - from 75.8 % (Tre) to 89.6% (Fen). The amount of digestible energy in the analyzed varieties of oats and barley was an average compound 13.74 MJ/kg DM and 14.85 MJ/kg DM, respectively. An analysis of the results showed that different varieties of oats compared with barley are preferable for horse nutrition according to the crude fat, crude fiber, ash and separate amino acids content, but the analyzed barley varieties dominated the higher amounts of crude protein, the digestible Liz amount and higher DE content, and thus, could be recommended for making feed formulation for horses combining oats and barley, taking into account the chemical composition of using cereal varieties.

Keywords: Barley, digestive energy, horses, nutritional value, oats.

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2251 Influence of Moringa Leaves Extract on the Response of Hb Molecule to Dose Rates’ Changes: II. Relaxation Time and Its Thermodynamic Driven State Functions

Authors: Mohamed M. M. Elnasharty, Azhar M. Elwan

Abstract:

Irradiation deposits energy through ionisation changing the bio-system’s net dipole, allowing the use of dielectric parameters and thermodynamic state functions related to these parameters as biophysical detectors to electrical inhomogeneity within the biosystem. This part is concerned with the effect of Moringa leaves extract, natural supplement, on the response of the biosystem to two different dose rates of irradiation. Having Hb molecule as a representative to the biosystem to be least invasive to the biosystem, dielectric measurements were used to extract the relaxation time of certain process found in the Hb spectrum within the indicated frequency window and the interrelated thermodynamic state functions were calculated from the deduced relaxation time. The results showed that relaxation time was decreased for both dose rates indicating a strong influence of Moringa on the response of biosystem and consequently Hb molecule. This influence was presented in the relaxation time and other parameters as well.

Keywords: Activation energy, DC conductivity, dielectric relaxation, enthalpy change, moringa leaves extract, relaxation time.

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2250 Analysis of Possibilities for Using Recycled Concrete Aggregate in Concrete Pavement

Authors: R. Pernicova, D. Dobias

Abstract:

The present article describes the limits of using recycled concrete aggregate (denoted as RCA) in the top layer of concrete roads. The main aim of this work is to investigate the possibility of reuse of recycled aggregates obtained by crushing the old concrete roads as a building material in the new top layers of concrete pavements. The paper is based on gathering the current knowledge about how to use recycled concrete aggregate, suitability, and modification of the properties and its standards. Regulations are detailed and described especially for European Union and for Czech Republic.

Keywords: Concrete, Czech Republic, pavements, recycled concrete aggregate, RCA, standards.

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2249 District 10 in Tehran: Urban Transformation and the Survey Evidence of Loss in Place Attachment in High Rises

Authors: Roya Morad, W. Eirik Heintz

Abstract:

The identity of a neighborhood is inevitably shaped by the architecture and the people of that place. Conventionally the streets within each neighborhood served as a semi-public-private extension of the private living spaces. The street as a design element formed a hybrid condition that was neither totally public nor private, and it encouraged social interactions. Thus through creating a sense of community, one of the most basic human needs of belonging was achieved. Similar to major global cities, Tehran has undergone serious urbanization. Developing into a capital city of high rises has resulted in an increase in urban density. Although allocating more residential units in each neighborhood was a critical response to the population boom and the limited land area of the city, it also created a crisis in terms of social communication and place attachment. District 10 in Tehran is a neighborhood that has undergone the most urban transformation among the other 22 districts in the capital and currently has the highest population density. This paper will explore how the active streets in district 10 have changed into their current condition of high rises with a lack of meaningful social interactions amongst its inhabitants. A residential building can be thought of as a large group of people. One would think that as the number of people increases, the opportunities for social communications would increase as well. However, according to the survey, there is an indirect relationship between the two. As the number of people of a residential building increases, the quality of each acquaintance reduces, and the depth of relationships between people tends to decrease. This comes from the anonymity of being part of a crowd and the lack of social spaces characterized by most high-rise apartment buildings. Without a sense of community, the attachment to a neighborhood is decreased. This paper further explores how the neighborhood participates to fulfill ones need for social interaction and focuses on the qualitative aspects of alternative spaces that can redevelop the sense of place attachment within the community.

Keywords: High density, place attachment, social communication, street life, urban transformation.

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2248 Characteristics of Maximum Gliding Endurance Path for High-Altitude Solar UAVs

Authors: Gao Xian-Zhong, Hou Zhong-xi, Guo Zheng, Liu Jian-xia

Abstract:

Gliding during night without electric power is an efficient method to enhance endurance performance of solar aircrafts. The properties of maximum gliding endurance path are studied in this paper. The problem is formulated as an optimization problem about maximum endurance can be sustained by certain potential energy storage with dynamic equations and aerodynamic parameter constrains. The optimal gliding path is generated based on gauss pseudo-spectral method. In order to analyse relationship between altitude, velocity of solar UAVs and its endurance performance, the lift coefficient in interval of [0.4, 1.2] and flight envelopes between 0~30km are investigated. Results show that broad range of lift coefficient can improve solar aircrafts- long endurance performance, and it is possible for a solar aircraft to achieve the aim of long endurance during whole night just by potential energy storage.

Keywords: Solar UAVs, Gliding Endurance, gauss pseudo-spectral method, optimization problem

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2247 Decision Tree for Competing Risks Survival Probability in Breast Cancer Study

Authors: N. A. Ibrahim, A. Kudus, I. Daud, M. R. Abu Bakar

Abstract:

Competing risks survival data that comprises of more than one type of event has been used in many applications, and one of these is in clinical study (e.g. in breast cancer study). The decision tree method can be extended to competing risks survival data by modifying the split function so as to accommodate two or more risks which might be dependent on each other. Recently, researchers have constructed some decision trees for recurrent survival time data using frailty and marginal modelling. We further extended the method for the case of competing risks. In this paper, we developed the decision tree method for competing risks survival time data based on proportional hazards for subdistribution of competing risks. In particular, we grow a tree by using deviance statistic. The application of breast cancer data is presented. Finally, to investigate the performance of the proposed method, simulation studies on identification of true group of observations were executed.

Keywords: Competing risks, Decision tree, Simulation, Subdistribution Proportional Hazard.

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2246 Radiation Heat Transfer in Planar SOFC Components: Application of the Lattice Boltzmann Method

Authors: Imen Mejri, Ahmed Mahmoudi, Mohamed A. Abbassi, Ahmed Omri

Abstract:

Thermal radiation plays a very important role in the heat transfer combination through the various components of the SOFC fuel cell operating at high temperatures. Lattice Boltzmann method is used for treating conduction-radiation heat transfer in the electrolyte. The thermal radiation heat transfer is coupled to the overall energy conservation equations through the divergence of the local radiative flux. The equation of energy in one dimension is numerically resolved by using the Lattice Boltzmann method. A computing program (FORTRAN) is developed locally for this purpose in order to obtain fields of temperature in every element of the cell. The parameters investigated are: functioning temperature, cell voltages and electrolyte thickness. The results show that the radiation effect increases with increasing the electrolyte thickness, also increases with increasing the functioning temperature and decreases with the increase of the voltage of the cell.

Keywords: SOFC, lattice Boltzmann method, conduction, radiation, planar medium.

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2245 Negative Pressure Waves in Hydraulic Systems

Authors: Fuad H. Veliev

Abstract:

Negative pressure phenomenon appears in many thermodynamic, geophysical and biophysical processes in the Nature and technological systems. For more than 100 years of the laboratory researches beginning from F. M. Donny’s tests, the great values of negative pressure have been achieved. But this phenomenon has not been practically applied, being only a nice lab toy due to the special demands for the purity and homogeneity of the liquids for its appearance. The possibility of creation of direct wave of negative pressure in real heterogeneous liquid systems was confirmed experimentally under the certain kinetic and hydraulic conditions. The negative pressure can be considered as the factor of both useful and destroying energies. The new approach to generation of the negative pressure waves in impure, unclean fluids has allowed the creation of principally new energy saving technologies and installations to increase the effectiveness and efficiency of different production processes. It was proved that the negative pressure is one of the main factors causing hard troubles in some technological and natural processes. Received results emphasize the necessity to take into account the role of the negative pressure as an energy factor in evaluation of many transient thermohydrodynamic processes in the Nature and production systems.

Keywords: Liquid systems, negative pressure, temperature, wave, metastable state.

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2244 Flow and Heat Transfer Mechanism Analysis in Outward Convex Asymmetrical Corrugated Tubes

Authors: Huaizhi Han, Bingxi Li, Yurong He, Rushan Bie, Zhao Wu

Abstract:

The flow and heat transfer mechanism in convex corrugated tubes have been investigated through numerical simulations in this paper. Two kinds of tube types named as symmetric corrugated tube (SCT) and asymmetric corrugated tube (ACT) are modeled and studied numerically based on the RST model. The predictive capability of RST model is examined in the corrugation wall in order to check the reliability of RST model under the corrugation wall condition. We propose a comparison between the RST modelling the corrugation wall with existing direct numerical simulation of Maaß C and Schumann U [14]. The numerical results pressure coefficient at different profiles between RST and DNS are well matched. The influences of large corrugation tough radii to heat transfer and flow characteristic had been considered. Flow and heat transfer comparison between SCT and ACT had been discussed. The numerical results show that ACT exhibits higher overall heat transfer performance than SCT.

Keywords: Asymmetric corrugated tube, RST, DNS, flow and heat transfer mechanism.

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2243 A Robust Deterministic Energy Smart-Grid Decisional Algorithm for Agent-Based Management

Authors: C. Adam, G. Henri, T. Levent, J.-B. Mauro, A. -L. Mayet

Abstract:

This paper is concerning the application of a deterministic decisional pattern to a multi-agent system which would provide intelligence to a distributed energy smart grid at local consumer level. Development of multi-agent application involves agent specifications, analysis, design and realization. It can be implemented by following several decisional patterns. The purpose of present article is to suggest a new approach to control the smart grid system in a decentralized competitive approach. The proposed algorithmic solution results from a deterministic dichotomous approach based on environment observation. It uses an iterative process to solve automatic learning problems. Through memory of collected past tries, the algorithm monotonically converges to very steep system operation point in attraction basin resulting from weak system nonlinearity. In this sense, system is given by (local) constitutive elementary rules the intelligence of its global existence so that it can self-organize toward optimal operating sequence.

Keywords: Decentralized Competitive System, Distributed Smart Grid, Multi-Agent System

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2242 The Upconversion of co-doped Nd3+/Er3+Tellurite Glass

Authors: Azman, K., Sahar, M.R., Rohani, M.S.

Abstract:

Series of tellurite glass of the system 78TeO2-10PbO- 10Li2O-(2-x)Nd2O3-xEr2O3, where x = 0.5, 1.0, 1.5 and 2.0 was successfully been made. A study of upconversion luminescence of the Nd3+/Er3+ co-doped tellurite glass has been carried out. From Judd-Ofelt analysis, the experimental lifetime, exp. τ of the glass serie are found higher in the visible region as they varies from 65.17ms to 114.63ms, whereas in the near infrared region (NIR) the lifetime are varies from 2.133ms to 2.270ms. Meanwhile, the emission cross section,σ results are found varies from 0.004 x 1020 cm2 to 1.007 x 1020 cm2 with respect to composition. The emission spectra of the glass are found been contributed from Nd3+ and Er3+ ions by which nine significant transition peaks are observed. The upconversion mechanism of the co-doped tellurite glass has been shown in the schematic energy diagrams. In this works, it is found that the excited state-absorption (ESA) is still dominant in the upconversion excitation process as the upconversion excitation mechanism of the Nd3+ excited-state levels is accomplished through a stepwise multiphonon process. An efficient excitation energy transfer (ET) has been observed between Nd3+ as a donor and Er3+ as the acceptor. As a result, respective emission spectra had been observed.

Keywords: Tellurite glass, co-dopant, upconvertionluminescence spectra.

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2241 The Effect of Vertical Shear-Link in Improving the Seismic Performance of Structures with Eccentrically Bracing Systems

Authors: Mohammad Reza Baradaran, Farhad Hamzezarghani, Mehdi Rastegari Ghiri, Zahra Mirsanjari

Abstract:

Passive control methods can be utilized to build earthquake resistant structures, and also to strengthen the vulnerable ones. In this paper, we studied the effect of this system in increasing the ductility and energy dissipation and also modeled the behavior of this type of eccentric bracing, and compared the hysteresis diagram of the modeled samples with the laboratory samples. We studied several samples of frames with vertical shear-links in order to assess the behavior of this type of eccentric bracing. Each of these samples was modeled in finite element software ANSYS 9.0, and was analyzed under the static cyclic loading. It was found that vertical shear-links have a more stable hysteresis loops. Another analysis showed that using honeycomb beams as the horizontal beam along with steel reinforcement has no negative effect on the hysteresis behavior of the sample.

Keywords: Vertical shear-link, passive control, cyclic analysis, energy dissipation, honeycomb beam.

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2240 Comparing Interval Estimators for Reliability in a Dependent Set-up

Authors: Alessandro Barbiero

Abstract:

In this paper some procedures for building confidence intervals for the reliability in stress-strength models are discussed and empirically compared. The particular case of a bivariate normal setup is considered. The confidence intervals suggested are obtained employing approximations or asymptotic properties of maximum likelihood estimators. The coverage and the precision of these intervals are empirically checked through a simulation study. An application to real paired data is also provided.

Keywords: Approximate estimators, asymptotic theory, confidence interval, Monte Carlo simulations, stress-strength, variance estimation.

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2239 Gas Injection Transport Mechanism for Shale Oil Recovery

Authors: Chinedu Ejike

Abstract:

The United States is now energy self-sufficient due to the production of shale oil reserves. With more than half of it being tapped daily in the United States, these unconventional reserves are massive and provide immense potential for future energy demands. Drilling horizontal wells and fracking are the primary methods for developing these reserves. Regrettably, recovery efficiency is rarely greater than 10%. Gas injection enhanced oil recovery offers a significant benefit in optimizing recovery of shale oil. This could be either through huff and puff, gas flooding, and cyclic gas injection. Methane, nitrogen, and carbon (IV) oxide, among other high-pressure gases, can be injected. Operators use Darcy's law to assess a reservoir's productive capacity, but they are unaware that the law may not apply to shale oil reserves. This is due to the fact that, unlike pressure differences alone, diffusion, concentration, and gas selection all play a role in the flow of gas injected into the wellbore. The reservoir drainage and oil sweep efficiency rates are determined by the transport method. This research evaluates the parameters that influence gas injection transport mechanism. Understanding the process could accelerate recovery by two to three times.

Keywords: enhanced oil recovery, gas injection, shale oil, transport mechanism, unconventional reservoir

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2238 Optimum Parameter of a Viscous Damper for Seismic and Wind Vibration

Authors: Soltani Amir, Hu Jiaxin

Abstract:

Determination of optimal parameters of a passive  control system device is the primary objective of this study.  Expanding upon the use of control devices in wind and earthquake  hazard reduction has led to development of various control systems.  The advantage of non-linearity characteristics in a passive control  device and the optimal control method using LQR algorithm are  explained in this study. Finally, this paper introduces a simple  approach to determine optimum parameters of a nonlinear viscous  damper for vibration control of structures. A MATLAB program is  used to produce the dynamic motion of the structure considering the  stiffness matrix of the SDOF frame and the non-linear damping  effect. This study concluded that the proposed system (variable  damping system) has better performance in system response control  than a linear damping system. Also, according to the energy  dissipation graph, the total energy loss is greater in non-linear  damping system than other systems.

 

Keywords: Passive Control System, Damping Devices, Viscous Dampers, Control Algorithm.

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2237 Demand Response from Residential Air Conditioning Load Using a Programmable Communication Thermostat

Authors: Saurabh Chanana, Monika Arora

Abstract:

Demand response is getting increased attention these days due to the increase in electricity demand and introduction of renewable resources in the existing power grid. Traditionally demand response programs involve large industrial consumers but with technological advancement, demand response is being implemented for small residential and commercial consumers also. In this paper, demand response program aims to reduce the peak demand as well as overall energy consumption of the residential customers. Air conditioners are the major reason of peak load in residential sector in summer, so a dynamic model of air conditioning load with thermostat action has been considered for applying demand response programs. A programmable communicating thermostat (PCT) is a device that uses real time pricing (RTP) signals to control the thermostat setting. A new model incorporating PCT in air conditioning load has been proposed in this paper. Results show that introduction of PCT in air conditioner is useful in reducing the electricity payments of customers as well as reducing the peak demand. 

Keywords: Demand response, Home energy management Programmable communicating thermostat, Thermostatically controlled appliances.

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2236 Optimization of Solar Tracking Systems

Authors: A. Zaher, A. Traore, F. Thiéry, T. Talbert, B. Shaer

Abstract:

In this paper, an intelligent approach is proposed to optimize the orientation of continuous solar tracking systems on cloudy days. Considering the weather case, the direct sunlight is more important than the diffuse radiation in case of clear sky. Thus, the panel is always pointed towards the sun. In case of an overcast sky, the solar beam is close to zero, and the panel is placed horizontally to receive the maximum of diffuse radiation. Under partly covered conditions, the panel must be pointed towards the source that emits the maximum of solar energy and it may be anywhere in the sky dome. Thus, the idea of our approach is to analyze the images, captured by ground-based sky camera system, in order to detect the zone in the sky dome which is considered as the optimal source of energy under cloudy conditions. The proposed approach is implemented using experimental setup developed at PROMES-CNRS laboratory in Perpignan city (France). Under overcast conditions, the results were very satisfactory, and the intelligent approach has provided efficiency gains of up to 9% relative to conventional continuous sun tracking systems.

Keywords: Clouds detection, fuzzy inference systems, images processing, sun trackers.

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2235 Competitor Analysis to Quantify the Benefits and for Different Use of Transport Infrastructure

Authors: Dimitrios J. Dimitriou, Maria F. Sartzetaki

Abstract:

Different transportation modes have key operational advantages and disadvantages, providing a variety of different transport options to users and passengers. This paper reviews key variables for the competition between air transport and other transport modes. The aim of this paper is to review the competition between air transport and other transport modes, providing results in terms of perceived cost for the users, for destinations high competitiveness for all transport modes. The competitor analysis variables include the cost and time outputs for each transport option, highlighting the level of competitiveness on high demanded Origin-Destination corridors. The case study presents the output of a such analysis for the OD corridor in Greece that connects the Capital city (Athens) with the second largest city (Thessaloniki) and the different transport modes have been considered (air, train, road). Conventional wisdom is to present an easy to handle tool for planners, managers and decision makers towards pricing policy effectiveness and demand attractiveness, appropriate to use for other similar cases.

Keywords: Competitor analysis, generalized cost, transport economics, quantitative modelling.

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2234 Using Jumping Particle Swarm Optimization for Optimal Operation of Pump in Water Distribution Networks

Authors: R. Rajabpour, N. Talebbeydokhti, M. H. Ahmadi

Abstract:

Carefully scheduling the operations of pumps can be resulted to significant energy savings. Schedules can be defined either implicit, in terms of other elements of the network such as tank levels, or explicit by specifying the time during which each pump is on/off. In this study, two new explicit representations based on timecontrolled triggers were analyzed, where the maximum number of pump switches was established beforehand, and the schedule may contain fewer switches than the maximum. The optimal operation of pumping stations was determined using a Jumping Particle Swarm Optimization (JPSO) algorithm to achieve the minimum energy cost. The model integrates JPSO optimizer and EPANET hydraulic network solver. The optimal pump operation schedule of VanZyl water distribution system was determined using the proposed model and compared with those from Genetic and Ant Colony algorithms. The results indicate that the proposed model utilizing the JPSO algorithm is a versatile management model for the operation of realworld water distribution system.

Keywords: JPSO, operation, optimization, water distribution system.

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2233 Study of Base-Isolation Building System

Authors: G. W. Ni, Y. M. Zhang, D. L. Jiang, J. N. Chen, B. Liu

Abstract:

In order to improve the effect of isolation structure, the principles and behaviours of the base-isolation system are studied, and the types and characteristics of the base-isolation are also discussed. Compared to the traditional aseismatic structures, the base isolation structures decrease the seismic response obviously: the total structural aseismatic value decreases to 1/4-1/32 and the seismic shear stress in the upper structure decreases to 1/14-1/23. In the huge seism, the structure can have an obvious aseismatic effect.

Keywords: Base-isolation, earthquake wave, dynamic response.

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2232 Hydrogen Production from Dehydrogenation of Ethanol over Ag-Based Catalysts

Authors: S. Totong, K. Faungnawakij, N. Laosiripojana

Abstract:

The development of alternative energy is interesting in the present especially, hydrogen production because it is an important energy resource in the future. This paper studied the hydrogen production from catalytic dehydrogenation of ethanol through via low temperature (<500°C) reaction. Copper (Cu) and silver (Ag) supported on fumed silica (SiO2) were selected in the present work; in addition, bimetallic material; Ag-Cu supported on SiO2 was also investigated. The catalysts were prepared by the incipient wetness impregnation method and characterized via X-ray diffraction (XRD), temperature-programmed reduction (TPR)and nitrogen adsorption measurements. The catalytic dehydrogenation of ethanol was carried out in a fixed bed continuous flow reactor at atmospheric pressure. The effect of reaction temperature between 300-375°C was studied in order to maximize the hydrogen yield. It was found that Ag-Cu/SiO2 exhibited the highest hydrogen yield compared to Ag/SiO2 and Cu/SiO2 at low reaction temperature (300°C) with full ethanol conversion. The highest hydrogen yield observed was 40% and will be further used as a reactant in fuel cells to generate electricity or feedstock of chemical production. 

Keywords: Catalyst, dehydrogenation, ethanol, hydrogen production.

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2231 Mechanical Properties of Ultra High Performance Concrete

Authors: Prabhat Ranjan Prem, B.H.Bharatkumar, Nagesh R Iyer

Abstract:

A research program is conducted to evaluate the mechanical properties of Ultra High Performance Concrete, target compressive strength at the age of 28 days being more than 150 MPa. The methodology to develop such mix has been explained. The material properties, mix design and curing regime are determined. The material attributes are understood by studying the stress strain behaviour of UHPC cylinders under uniaxial compressive loading. The load –crack mouth opening displacement (cmod) of UHPC beams, flexural strength and fracture energy was evaluated using third point loading test. Compressive strength and Split tensile strength results are determined to find out the compressive and tensile behaviour. Residual strength parameters are presented vividly explaining the flexural performance, toughness of concrete.Durability studies were also done to compare the effect of fibre to that of a control mix For all the studies the Mechanical properties were evaluated by varying the percentage and aspect ratio of steel fibres The results reflected that higher aspect ratio and fibre volume produced drastic changes in the cube strength, cylinder strength, post peak response, load-cmod, fracture energy flexural strength, split tensile strength, residual strength and durability. In regards to null application of UHPC in India, an initiative is undertaken to comprehend the mechanical behaviour of UHPC, which will be vital for longer run in commercialization for structural applications.

Keywords: Ultra High Performance Concrete, Reinforcement Index, Compressive Strength, Tensile Strength, Flexural Strength, Residual Strength, Fracture Energy, Stress-Strain Relationships, Load-Crack Mouth Opening Displacement and Durability.

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