Search results for: failed fuel detector (FFD)
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2508

Search results for: failed fuel detector (FFD)

1548 Failure Analysis: Solid Rocket Motor Type “Candy” - Explosion in a Static Test

Authors: Diego Romero, Fabio Rojas, J. Alejandro Urrego

Abstract:

The sounding rockets are aerospace vehicles that were developed in the mid-20th century, and Colombia has been involved in research that was carried out with the aim of innovating with this technology. The rockets are university research programs with the collaboration of the local government, with a simple strategy, develop and reduce the greatest costs associated with the production of a kind type of technology. In this way, in this document presents the failure analysis of a solid rocket motor, with the real compatibly to reach the thermosphere with a low-cost fuel. This solid rocket motor is the latest development of the Uniandes Aerospace Project (PUA for its Spanish acronym), an undergraduate and postgraduate research group at Universidad de los Andes (Bogotá, Colombia), dedicated to incurring in this type of technology. This motor has been carried out on Candy-type solid fuel, which is a compound of potassium nitrate and sorbitol, and the investigation has allowed the production of solid motors powerful enough to reach space, and which represents a unique technological advance in Latin America and an important development in experimental rocketry.To outline the main points the explosion in a static test is an important to explore and demonstrate the ways to develop technology, methodologies, production and manufacturing, being a solid rocket motor with 30 kN of thrust. In conclusion, this analysis explores different fields such as: design, manufacture, materials, production, first fire and more, with different engineering tools with principal objective find root failure. Following the engineering analysis methodology, was possible to design a new version of motor, with learned lessons new manufacturing specification, therefore, when publishing this project, it is intended to be a reference for future research in this field and benefit the industry.

Keywords: candy propellant, candy rockets, explosion, failure analysis, static test, solid rocket motor

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1547 Non-Invasive Imaging of Human Tissue Using NIR Light

Authors: Ashwani Kumar

Abstract:

Use of NIR light for imaging the biological tissue and to quantify its optical properties is a good choice over other invasive methods. Optical tomography involves two steps. One is the forward problem and the other is the reconstruction problem. The forward problem consists of finding the measurements of transmitted light through the tissue from source to detector, given the spatial distribution of absorption and scattering properties. The second step is the reconstruction problem. In X-ray tomography, there is standard method for reconstruction called filtered back projection method or the algebraic reconstruction methods. But this method cannot be applied as such, in optical tomography due to highly scattering nature of biological tissue. A hybrid algorithm for reconstruction has been implemented in this work which takes into account the highly scattered path taken by photons while back projecting the forward data obtained during Monte Carlo simulation. The reconstructed image suffers from blurring due to point spread function.

Keywords: NIR light, tissue, blurring, Monte Carlo simulation

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1546 Sociological Enquiry into Occupational Risks and Its Consequences among Informal Automobile Artisans in Osun State, Nigeria

Authors: Funmilayo Juliana Afolabi, Joke Haafkens, Paul De Beer

Abstract:

Globally, there is a growing concern on reducing workplace accidents in the informal sector. However, there is a dearth of study on the perception of the informal workers on occupational risks they are exposed to. The way a worker perceives the workplace risk will influence his/her risk tolerance and risk behavior. The aim of this paper, therefore, is to have an in-depth understanding of the way the artisans perceive the risks at their workplace and how it influences their risk tolerance and risk behavior. This will help in designing meaningful intervention for the artisans and it will assist the policy makers in formulating a policy that will help them. Methods: Forty-three artisans were purposely selected for the study; data were generated through observation of the workplace and work practices of the artisans and in-depth interview from automobile artisans (Panel beater, Mechanic, Vulcanizer, and Painters) in Osun State, Nigeria. The transcriptions were coded and analyzed using MAXQDA software. Results: The perceived occupational risks among the study groups are a danger of being run over by oncoming vehicles while working by the roadside, a risk of vehicle falling on workers while working under the vehicle, cuts, and burns, fire explosion, falls from height and injuries from bursting of tires. The identified risk factors are carelessness of the workers, pressure from customers, inadequate tools, preternatural forces, God’s will and lack of apprentices that will assist them in the workplace. Furthermore, the study revealed that artisans engage in risky behavior like siphoning fuel with mouth because of perception that fuel is good for expelling worms and will make them free from any stomach upset. Conclusions: The study concluded that risky behaviors are influenced by culture, beliefs, and perception of the artisans. The study, therefore, suggested proper health and safety education for the artisans.

Keywords: automobile artisans, informal, occupational risks, Nigeria, sociological enquiry

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1545 Optical Heterodyning of Injection-Locked Laser Sources: A Novel Technique for Millimeter-Wave Signal Generation

Authors: Subal Kar, Madhuja Ghosh, Soumik Das, Antara Saha

Abstract:

A novel technique has been developed to generate ultra-stable millimeter-wave signal by optical heterodyning of the output from two slave laser (SL) sources injection-locked to the sidebands of a frequency modulated (FM) master laser (ML). Precise thermal tuning of the SL sources is required to lock the particular slave laser frequency to the desired FM sidebands of the ML. The output signals from the injection-locked SL when coherently heterodyned in a fast response photo detector like high electron mobility transistor (HEMT), extremely stable millimeter-wave signal having very narrow line width can be generated. The scheme may also be used to generate ultra-stable sub-millimeter-wave/terahertz signal.

Keywords: FM sideband injection locking, master-slave injection locking, millimetre-wave signal generation, optical heterodyning

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1544 Development of Innovative Nuclear Fuel Pellets Using Additive Manufacturing

Authors: Paul Lemarignier, Olivier Fiquet, Vincent Pateloup

Abstract:

In line with the strong desire of nuclear energy players to have ever more effective products in terms of safety, research programs on E-ATF (Enhanced-Accident Tolerant Fuels) that are more resilient, particularly to the loss of coolant, have been launched in all countries with nuclear power plants. Among the multitude of solutions being developed internationally, carcinoembryonic antigen (CEA) and its partners are investigating a promising solution, which is the realization of CERMET (CERamic-METal) type fuel pellets made of a matrix of fissile material, uranium dioxide UO2, which has a low thermal conductivity, and a metallic phase with a high thermal conductivity to improve heat evacuation. Work has focused on the development by powder metallurgy of micro-structured CERMETs, characterized by networks of metallic phase embedded in the UO₂ matrix. Other types of macro-structured CERMETs, based on concepts proposed by thermal simulation studies, have been developed with a metallic phase with a specific geometry to optimize heat evacuation. This solution could not be developed using traditional processes, so additive manufacturing, which revolutionizes traditional design principles, is used to produce these innovative prototype concepts. At CEA Cadarache, work is first carried out on a non-radioactive surrogate material, alumina, in order to acquire skills and to develop the equipment, in particular the robocasting machine, an additive manufacturing technique selected for its simplicity and the possibility of optimizing the paste formulations. A manufacturing chain was set up, with the pastes production, the 3D printing of pellets, and the associated thermal post-treatment. The work leading to the first elaborations of macro-structured alumina/molybdenum CERMETs will be presented. This work was carried out with the support of Framatome and EdF.

Keywords: additive manufacturing, alumina, CERMET, molybdenum, nuclear safety

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1543 Influence of Shock Absorber Condition on the Vertical Dynamic Load Applied on the Pavement by a Truck’s Front Suspension

Authors: Pablo Kubo, Cassio Paiva, Adelino Ferreira

Abstract:

The main objective of this research study is to present the results of the influence of shock absorber condition, from a truck front suspension, on the vertical dynamic load applied on the pavement. For the measurements, it has been used a durability test track located in Brazil. The shock absorber conditions were new, used and failed with a constant load of 6 tons on the front suspension, the maximum allowed load for front axle according to Brazilian legislation. By applying relative damage concept, it is possible to conclude that the variation on the shock absorber conditions will significantly affect the load applied on the pavement. Although, it is recommended to repeat the same methodology in order to analyze the influence on the variation of the quarter car model variants.

Keywords: damage, shock absorber, vertical dynamic load, absorber

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1542 Sustainable Crop Mechanization among Small Scale Rural Farmers in Nigeria: The Hurdles

Authors: Charles Iledun Oyewole

Abstract:

The daunting challenge that the ‘man with the hoe’ is going to face in the coming decades will be complex and interwoven. With global population already above 7 billion people, it has been estimated that food (crop) production must more than double by 2050 to meet up with the world’s food requirements. Nigeria population is also expected to reach over 240 million people by 2050, at the current annual population growth of 2.61 per cent. The country’s farming population is estimated at over 65 per cent, but the country still depends on food importation to complement production. The small scale farmer, who depends on simple hand tools: hoes and cutlasses, remains the centre of agricultural production, accounting for 90 per cent of the total agricultural output and 80 per cent of the market flow. While the hoe may have been a tool for sustainable development at a time in human history, this role has been smothered by population growth, which has brought too many mouths to be fed (over 170 million), as well as many industries to fuel with raw materials. It may then be argued that the hoe is unfortunately not a tool for the coming challenges and that agricultural mechanization should be the focus. However, agriculture as an enterprise is a ‘complete wheel’ which does not work when broken, particularly, in respect to mechanization. Generally, mechanization will prompt increase production, where land is readily available; increase production, will require post-harvest handling mechanisms, crop processing and subsequent storage. An important aspect of this is readily available and favourable markets for such produce; fuel by good agricultural policies. A break in this wheel will lead to the process of mechanization crashing back to subsistence production, and probably reversal to the hoe. The focus of any agricultural policy should be to chart a course for sustainable mechanization that is environmentally friendly, that may ameliorate Nigeria’s food and raw material gaps. This is the focal point of this article.

Keywords: Crop production, Farmer, Hoes, Mechanization, Policy framework, Population, Growth, Rural areas

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1541 Metal (Loids) Speciation Using HPLC-ICP-MS Technique in Klodnica River, Upper Silesia, Poland

Authors: Magdalena Jabłońska-Czapla

Abstract:

The work allowed gaining knowledge about redox and speciation changes of As, Cr, and Sb ionic forms in Klodnica River water. This kind of studies never has been conducted in this region of Poland. In study optimized and validated previously HPLC-ICP-MS methods for determination of As, Sb and Cr was used. Separation step was done using high-performance liquid chromatograph equipped with ion-exchange column followed by ICP-MS spectrometer detector. Preliminary studies included determination of the total concentration of As, Sb and Cr, pH, Eh, temperature and conductivity of the water samples. The study was conducted monthly from March to August 2014, at six points on the Klodnica River. The results indicate that exceeded at acceptable concentration of total Cr and Sb was observed in Klodnica River and we should qualify Klodnica River waters below the second purity class. In Klodnica River waters dominates oxidized antimony and arsenic forms, as well as the two forms of chromium Cr(VI) and Cr(III). Studies have also shown the methyl derivative of arsenic's presence.

Keywords: antimony, arsenic, chromium, HPLC-ICP-MS, river water, speciation

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1540 Effects of Heat Treatment on the Elastic Constants of Cedar Wood

Authors: Tugba Yilmaz Aydin, Ergun Guntekin, Murat Aydin

Abstract:

Effects of heat treatment on the elastic constants of cedar wood (Cedrus libani) were investigated. Specimens were exposed to heat under atmospheric pressure at four different temperatures (120, 150, 180, 210 °C) and three different time levels (2, 5, 8 hours). Three Young’s modulus (EL, ER, ET) and six Poisson ratios (μLR, μLT, μRL, μRT, μTL, μTR) were determined from compression test using bi-axial extensometer at constant moisture content (12 %). Three shear modulus were determined using ultrasound. Six shear wave velocities propagating along the principal axes of anisotropy were measured using EPOCH 650 ultrasonic flaw detector with 1 MHz transverse transducers. The properties of the samples tested were significantly affected by heat treatment by different degree. As a result, softer treatments yielded some amount of increase in Young modulus and shear modulus values, but increase of time and temperature resulted in significant decrease for both values. Poisson ratios seemed insensitive to heat treatment.

Keywords: cedar wood, elastic constants, heat treatment, ultrasound

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1539 Performances of the Double-Crystal Setup at CERN SPS Accelerator for Physics beyond Colliders Experiments

Authors: Andrii Natochii

Abstract:

We are currently presenting the recent results from the CERN accelerator facilities obtained in the frame of the UA9 Collaboration. The UA9 experiment investigates how a tiny silicon bent crystal (few millimeters long) can be used for various high-energy physics applications. Due to the huge electrostatic field (tens of GV/cm) between crystalline planes, there is a probability for charged particles, impinging the crystal, to be trapped in the channeling regime. It gives a possibility to steer a high intensity and momentum beam by bending the crystal: channeled particles will follow the crystal curvature and deflect on the certain angle (from tens microradians for LHC to few milliradians for SPS energy ranges). The measurements at SPS, performed in 2017 and 2018, confirmed that the protons deflected by the first crystal, inserted in the primary beam halo, can be caught and channeled by the second crystal. In this configuration, we measure the single pass deflection efficiency of the second crystal and prove our opportunity to perform the fixed target experiment at SPS accelerator (LHC in the future).

Keywords: channeling, double-crystal setup, fixed target experiment, Timepix detector

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1538 Fabrication of Glucose/O₂ Microfluidic Biofuel Cell with Double Layer of Electrodes

Authors: Haroon Khan, Chul Min Kim, Sung Yeol Kim, Sanket Goel, Prabhat K. Dwivedi, Ashutosh Sharma, Gyu Man Kim

Abstract:

Enzymatic biofuel cells (EBFCs) have drawn the attention of researchers due to its demanding application in medical implants. In EBFCs, electricity is produced with the help of redox enzymes. In this study, we report the fabrication of membraneless EBFC with new design of electrodes to overcome microchannel related limitations. The device consists of double layer of electrodes on both sides of Y-shaped microchannel to reduce the effect of oxygen depletion layer and diffusion of fuel and oxidant at the end of microchannel. Moreover, the length of microchannel was reduced by half keeping the same area of multiwalled carbon nanotubes (MWCNT) electrodes. Polydimethylsiloxane (PDMS) stencils were used to pattern MWCNT electrodes on etched Indium Tin Oxide (ITO) glass. PDMS casting was used to fabricate microchannel of the device. Both anode and cathode were modified with glucose oxidase and laccase. Furthermore, these enzymes were covalently bound to carboxyl MWCNTs with the help of EDC/NHS. Glucose used as fuel was oxidized by glucose oxidase at anode while oxygen was reduced to water at the cathode side. The resulted devices were investigated with the help of polarization curves obtained from Chronopotentiometry technique by using potentiostat. From results, we conclude that the performance of double layer EBFC is improved 15 % as compared to single layer EBFC delivering maximum power density of 71.25 µW cm-2 at a cell potential of 0.3 V and current density of 250 µA cm-2 at micro channel height of 450-µm and flow rate of 25 ml hr-1. However, the new device was stable only for three days after which its power output was rapidly dropped by 75 %. This work demonstrates that the power output of membraneless EBFC is improved comparatively, but still efforts will be needed to make the device stable over long period of time.

Keywords: EBFC, glucose, MWCNT, microfluidic

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1537 Numerical Studies on Bypass Thrust Augmentation Using Convective Heat Transfer in Turbofan Engine

Authors: R. Adwaith, J. Gopinath, Vasantha Kohila B., R. Chandru, Arul Prakash R.

Abstract:

The turbofan engine is a type of air breathing engine that is widely used in aircraft propulsion produces thrust mainly from the mass-flow of air bypassing the engine core. The present research has developed an effective method numerically by increasing the thrust generated from the bypass air. This thrust increase is brought about by heating the walls of the bypass valve from the combustion chamber using convective heat transfer method. It is achieved computationally by the use external heat to enhance the velocity of bypass air of turbofan engines. The bypass valves are either heated externally using multicell tube resistor which convert electricity generated by dynamos into heat or heat is transferred from the combustion chamber. This increases the temperature of the flow in the valves and thereby increase the velocity of the flow that enters the nozzle of the engine. As a result, mass-flow of air passing the core engine for producing more thrust can be significantly reduced thereby saving considerable amount of Jet fuel. Numerical analysis has been carried out on a scaled down version of a typical turbofan bypass valve, where the valve wall temperature has been increased to 700 Kelvin. It is observed from the analysis that, the exit velocity contributing to thrust has significantly increased by 10 % due to the heating of by-pass valve. The degree of optimum increase in the temperature, and the corresponding effect in the increase of jet velocity is calculated to determine the operating temperature range for efficient increase in velocity. The technique used in the research increases the thrust by using heated by-pass air without extracting much work from the fuel and thus improve the efficiency of existing turbofan engines. Dimensional analysis has been carried to prove the accuracy of the results obtained numerically.

Keywords: turbofan engine, bypass valve, multi-cell tube, convective heat transfer, thrust

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1536 Controlled Synthesis of Pt₃Sn-SnOx/C Electrocatalysts for Polymer Electrolyte Membrane Fuel Cells

Authors: Dorottya Guban, Irina Borbath, Istvan Bakos, Peter Nemeth, Andras Tompos

Abstract:

One of the greatest challenges of the implementation of polymer electrolyte membrane fuel cells (PEMFCs) is to find active and durable electrocatalysts. The cell performance is always limited by the oxygen reduction reaction (ORR) on the cathode since it is at least 6 orders of magnitude slower than the hydrogen oxidation on the anode. Therefore high loading of Pt is required. Catalyst corrosion is also more significant on the cathode, especially in case of mobile applications, where rapid changes of loading have to be tolerated. Pt-Sn bulk alloys and SnO2-decorated Pt3Sn nanostructures are among the most studied bimetallic systems for fuel cell applications. Exclusive formation of supported Sn-Pt alloy phases with different Pt/Sn ratios can be achieved by using controlled surface reactions (CSRs) between hydrogen adsorbed on Pt sites and tetraethyl tin. In this contribution our results for commercial and a home-made 20 wt.% Pt/C catalysts modified by tin anchoring via CSRs are presented. The parent Pt/C catalysts were synthesized by modified NaBH4-assisted ethylene-glycol reduction method using ethanol as a solvent, which resulted either in dispersed and highly stable Pt nanoparticles or evenly distributed raspberry-like agglomerates according to the chosen synthesis parameters. The 20 wt.% Pt/C catalysts prepared that way showed improved electrocatalytic performance in the ORR and stability in comparison to the commercial 20 wt.% Pt/C catalysts. Then, in order to obtain Sn-Pt/C catalysts with Pt/Sn= 3 ratio, the Pt/C catalysts were modified with tetraethyl tin (SnEt4) using three and five consecutive tin anchoring periods. According to in situ XPS studies in case of catalysts with highly dispersed Pt nanoparticles, pre-treatment in hydrogen even at 170°C resulted in complete reduction of the ionic tin to Sn0. No evidence of the presence of SnO2 phase was found by means of the XRD and EDS analysis. These results demonstrate that the method of CSRs is a powerful tool to create Pt-Sn bimetallic nanoparticles exclusively, without tin deposition onto the carbon support. On the contrary, the XPS results revealed that the tin-modified catalysts with raspberry-like Pt agglomerates always contained a fraction of non-reducible tin oxide. At the same time, they showed increased activity and long-term stability in the ORR than Pt/C, which was assigned to the presence of SnO2 in close proximity/contact with Pt-Sn alloy phase. It has been demonstrated that the content and dispersion of the fcc Pt3Sn phase within the electrocatalysts can be controlled by tuning the reaction conditions of CSRs. The bimetallic catalysts displayed an outstanding performance in the ORR. The preparation of a highly dispersed 20Pt/C catalyst permits to decrease the Pt content without relevant decline in the electrocatalytic performance of the catalysts.

Keywords: anode catalyst, cathode catalyst, controlled surface reactions, oxygen reduction reaction, PtSn/C electrocatalyst

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1535 Variability of Energy Efficiency with the Application of Technologies Embedded in Locomotives of a Heavy Haul Railway: Case Study of Vitoria Minas Railway, Brazil

Authors: Eric Wilson Santos Cabral, Marta Monteiro Da Costa Cruz, Rodrigo Pirola Pestana, Vivian Andréa Parreira

Abstract:

In the transportation sector in Brazil, there is a great challenge that is the maintenance of profit in the face of the great variation in the price of diesel. This directly affects the variable cost of transport companies. Within the railways, part of the great challenges is to overcome the annual budget, cargo and ore transported, thus reducing costs compared to previous years, becoming more efficient each year. Within this scenario, the railway companies are looking for effective measures, aiming at reducing the ratio of liter of diesel consumed by KTKB (Kilometer Gross Ton multiplied by thousand). This ratio represents the indicator of energy efficiency of some railroads in Brazil and in other countries. In this study, we sought to analyze the behavior of the energy efficiency indicator on two parts: The first, with the application of technologies used in locomotives, such as the start-stop system of the diesel engine and the system of tracking and monitoring of fuel. The second, evaluation of the behavior of the variation of the type of cargo transported (loading mix). The study focused on locomotive technology will be carried out using statistical analysis, behavioral evaluation in different operating conditions, such as maneuvers for trains, service trains and freight trains. The analysis will also cover the evaluation of the loading mix made using statistical analysis of the existing railroad database, comparing the energy efficiency per loading mine and type of product. With the completion of this study, the railway undertakings should be able to better target decision-making in order to achieve substantial reductions in transport costs.

Keywords: railway transport, energy efficiency, railway technology, fuel consumption

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1534 Bioactive Chemical Markers Based Strategy for Quality Control of Herbal Medicines

Authors: Zhenzhong Yang

Abstract:

Herbal medicines are important supplements to chemical drugs and usually consist of a complex mixture of constituents. The current quality control strategy of herbal medicines is mainly based on chemical markers, which largely failed to owe to the markers, not reflecting the herbal medicines’ multiple mechanisms of action. Herein, a bioactive chemical markers based strategy was proposed and applied to the quality assessment and control of herbal medicines. This strategy mainly includes the comprehensive chemical characterization of herbal medicines, bioactive chemical markers identification, and related quantitative analysis methods development. As a proof-of-concept, this strategy was applied to a Panax notoginseng derived herbal medicine. The bioactive chemical markers based strategy offers a rational approach for quality assessment and control of herbal medicines.

Keywords: bioactive chemical markers, herbal medicines, quality assessment, quality control

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1533 Surge Analysis of Water Transmission Mains in Una, Himachal Pradesh, India

Authors: Baldev Setia, Raj Rajeshwari, Maneesh Kumar

Abstract:

Present paper is an analysis of water transmission mains failed due to surge analysis by using basic software known as Surge Analysis Program (SAP). It is a real time failure case study of a pipe laid in Una, Himachal Pradesh. The transmission main is a 13 kilometer long pipe with 7.9 kilometers as pumping main and 5.1 kilometers as gravitational main. The analysis deals with mainly pumping mains. The results are available in two text files. Besides, several files are prepared with specific view to obtain results in a graphical form. These results help to observe the pressure difference and surge occurrence at different locations along the pipe profile, which help to redesign the transmission main with different but suitable safety measures against possible surge. A technically viable and economically feasible design has been provided as per the relevant manual and standard code of practice.

Keywords: surge, water hammer, transmission mains, SAP 2000

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1532 Physico-Chemical Parameters and Economic Evaluation of Bio-Ethanol Produced from Waste of Starting Dates in South Algeria

Authors: Insaf Mehani, Bachir Bouchekima

Abstract:

The fight against climate change and the replacement of fossil energies nearing exhaustion gradually emerge as major societal and economic challenges. It is possible to develop common dates of low commercial value, and put on the local and international market a new generation of products with high added values such as bio ethanol. Besides its use in chemical synthesis, bio ethanol can be blended with gasoline to produce a clean fuel while improving the octane.

Keywords: bio-energy, waste dates, bio ethanol, Algeria

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1531 Surge Analysis of Water Transmission Mains in Una, Himachal Pradesh (India)

Authors: Baldev Setia, Raj Rajeshwari, Maneesh Kumar

Abstract:

Present paper is an analysis of water transmission mains failed due to surge analysis by using basic software known as Surge Analysis Program (SAP). It is a real time failure case study of a pipe laid in Una, Himachal Pradesh. The transmission main is a 13 kilometres long pipe with 7.9 kilometres as pumping main and 5.1 kilometres as gravitational main. The analysis deals with mainly pumping mains. The results are available in two text files. Besides, several files are prepared with specific view to obtain results in a graphical form. These results help to observe the pressure difference and surge occurrence at different locations along the pipe profile, which help to redesign the transmission main with different but suitable safety measures against possible surge. A technically viable and economically feasible design has been provided as per the relevant manual and standard code of practice.

Keywords: surge, water hammer, transmission mains, SAP 2000

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1530 Low-Noise Amplifier Design for Improvement of Communication Range for Wake-Up Receiver Based Wireless Sensor Network Application

Authors: Ilef Ketata, Mohamed Khalil Baazaoui, Robert Fromm, Ahmad Fakhfakh, Faouzi Derbel

Abstract:

The integration of wireless communication, e. g. in real-or quasi-real-time applications, is related to many challenges such as energy consumption, communication range, latency, quality of service, and reliability. To minimize the latency without increasing energy consumption, wake-up receiver (WuRx) nodes have been introduced in recent works. Low-noise amplifiers (LNAs) are introduced to improve the WuRx sensitivity but increase the supply current severely. Different WuRx approaches exist with always-on, power-gated, or duty-cycled receiver designs. This paper presents a comparative study for improving communication range and decreasing the energy consumption of wireless sensor nodes.

Keywords: wireless sensor network, wake-up receiver, duty-cycled, low-noise amplifier, envelope detector, range study

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1529 Evaluation of Progressive Collapse of Transmission Tower

Authors: Jeong-Hwan Choi, Hyo-Sang Park, Tae-Hyung Lee

Abstract:

The transmission tower is one of the crucial lifeline structures in a modern society, and it needs to be protected against extreme loading conditions. However, the transmission tower is a very complex structure and, therefore, it is very difficult to simulate the actual damage and the collapse behavior of the tower structure. In this study, the actual collapse behavior of the transmission tower due to lateral loading conditions such as wind load is evaluated through the computational simulation. For that, a progressive collapse procedure is applied to the simulation. In this procedure, after running the simulation, if a member of the tower structure fails, the failed member is removed and the simulation run again. The 154kV transmission tower is selected for this study. The simulation is performed by nonlinear static analysis procedure, namely pushover analysis, using OpenSEES, an earthquake simulation platform. Three-dimensional finite element models of those towers are developed.

Keywords: transmission tower, OpenSEES, pushover, progressive collapse

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1528 Effect of Environmental Parameters on the Water Solubility of the Polycyclic Aromatic Hydrocarbons and Derivatives using Taguchi Experimental Design Methodology

Authors: Pranudda Pimsee, Caroline Sablayrolles, Pascale De Caro, Julien Guyomarch, Nicolas Lesage, Mireille Montréjaud-Vignoles

Abstract:

The MIGR’HYCAR research project was initiated to provide decisional tools for risks connected to oil spill drifts in continental waters. These tools aim to serve in the decision-making process once oil spill pollution occurs and/or as reference tools to study scenarios of potential impacts of pollutions on a given site. This paper focuses on the study of the distribution of polycyclic aromatic hydrocarbons (PAHs) and derivatives from oil spill in water as function of environmental parameters. Eight petroleum oils covering a representative range of commercially available products were tested. 41 Polycyclic Aromatic Hydrocarbons (PAHs) and derivate, among them 16 EPA priority pollutants were studied by dynamic tests at laboratory scale. The chemical profile of the water soluble fraction was different from the parent oil profile due to the various water solubility of oil components. Semi-volatile compounds (naphtalenes) constitute the major part of the water soluble fraction. A large variation in composition of the water soluble fraction was highlighted depending on oil type. Moreover, four environmental parameters (temperature, suspended solid quantity, salinity, and oil: water surface ratio) were investigated with the Taguchi experimental design methodology. The results showed that oils are divided into three groups: the solubility of Domestic fuel and Jet A1 presented a high sensitivity to parameters studied, meaning they must be taken into account. For gasoline (SP95-E10) and diesel fuel, a medium sensitivity to parameters was observed. In fact, the four others oils have shown low sensitivity to parameters studied. Finally, three parameters were found to be significant towards the water soluble fraction.

Keywords: mornitoring, PAHs, water soluble fraction, SBSE, Taguchi experimental design

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1527 A Study on the Residential Estate Development and Management by Defence Housing Authority (DHA) in Lahore

Authors: Zareen Shahid

Abstract:

Rapid increase in population has resulted in uncontrolled and unplanned growth of metropolitan cities in Pakistan. Pakistan is facing unprecedented challenges of acute housing shortages, unhealthy living conditions and a non-existent or dilapidated infrastructure across the country. The government of Pakistan has also failed to devise a comprehensive and long-term strategy to cope with the problem of housing and better infrastructure development and management that has resulted in congestion, overcrowding and deterioration of environment in cities. On the other hand public has developed intense faith upon Defence Housing Authority (DHA) Lahore. This research paper is about to observe the difference in residential estate development and services provided by DHA Lahore. This paper attempts to identify the factors which are contributing towards the success of DHA and recommend measures for improvement in public sector for betterment.

Keywords: residential estate, development and management, defence housing authority

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1526 Technological and Economic Investigation of Concentrated Photovoltaic and Thermal Systems: A Case Study of Iran

Authors: Moloud Torkandam

Abstract:

Any cities must be designed and built in a way that minimizes their need for fossil fuel. Undoubtedly, the necessity of accepting this principle in the previous eras is undeniable with respect to the mode of constructions. Perhaps only due to the great diversity of materials and new technologies in the contemporary era, such a principle in buildings has been forgotten. The question of optimizing energy consumption in buildings has attracted a great deal of attention in many countries and, in this way, they have been able to cut down the consumption of energy up to 30 percent. The energy consumption is remarkably higher than global standards in our country, and the most important reason is the undesirable state of buildings from the standpoint of energy consumption. In addition to providing the means to protect the natural and fuel resources for the future generations, reducing the use of fossil energies may also bring about desirable outcomes such as the decrease in greenhouse gases (whose emissions cause global warming, the melting of polar ice, the rise in sea level and the climatic changes of the planet earth), the decrease in the destructive effects of contamination in residential complexes and especially urban environments and preparation for national self-sufficiency and the country’s independence and preserving national capitals. This research realize that in this modern day and age, living sustainably is a pre-requisite for ensuring a bright future and high quality of life. In acquiring this living standard, we will maintain the functions and ability of our environment to serve and sustain our livelihoods. Electricity is now an integral part of modern life, a basic necessity. In the provision of electricity, we are committed to respecting the environment by reducing the use of fossil fuels through the use of proven technologies that use local renewable and natural resources as its energy source. As far as this research concerned it is completely necessary to work on different type of energy producing such as solar and CPVT system.

Keywords: energy, photovoltaic, termal system, solar energy, CPVT

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1525 Spectral Anomaly Detection and Clustering in Radiological Search

Authors: Thomas L. McCullough, John D. Hague, Marylesa M. Howard, Matthew K. Kiser, Michael A. Mazur, Lance K. McLean, Johanna L. Turk

Abstract:

Radiological search and mapping depends on the successful recognition of anomalies in large data sets which contain varied and dynamic backgrounds. We present a new algorithmic approach for real-time anomaly detection which is resistant to common detector imperfections, avoids the limitations of a source template library and provides immediate, and easily interpretable, user feedback. This algorithm is based on a continuous wavelet transform for variance reduction and evaluates the deviation between a foreground measurement and a local background expectation using methods from linear algebra. We also present a technique for recognizing and visualizing spectrally similar clusters of data. This technique uses Laplacian Eigenmap Manifold Learning to perform dimensional reduction which preserves the geometric "closeness" of the data while maintaining sensitivity to outlying data. We illustrate the utility of both techniques on real-world data sets.

Keywords: radiological search, radiological mapping, radioactivity, radiation protection

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1524 Replacement Time and Number of Preventive Maintenance Actions for Second-Hand Device

Authors: Wen Liang Chang

Abstract:

In this study, the optimal replacement time and number of preventive maintenance (PM) actions were investigated for a second-hand device. Suppose that a user intends to use a second-hand device for manufacturing products, and that the device is replaced with a new one. Any device failure is rectified through minimal repair, thereby incurring a fixed repair cost to the user. If the new device fails within the FRW period, minimal repair is performed at no cost to the user. After the FRW expires, a failed device is repaired and the cost of repair is incurred by the user. In this study, two profit models were developed, and the optimal replacement time and number of PM actions were determined to maximize profits. Finally, the influence of the optimal replacement time and number of PM actions were elaborated on, using numerical examples.

Keywords: second-hand device, preventive maintenance, replacement time, device failure

Procedia PDF Downloads 458
1523 The Professionalisation of British Intelligence Analysts

Authors: Michael S. Goodman

Abstract:

The Joint Intelligence Committee (JIC) has been the senior most analytical body in the UK since its creation in 1936. At various points in its history, most notably and recently in 2004, in the wake of the Iraq war, questions have been asked about its analytical process. In 1968 the British intelligence community saw one of its biggest transformations: the creation of an independent, central cadre of analysts. The ‘Assessments Staff’ was a novel attempt to improve the quality of analysis by fostering independence from departmental biases that had long plagued British intelligence. Seconded into the Cabinet Office, staff were allocated a ‘desk,’ and their role was to produce high level assessments for the most senior readers in the land. At the same time, efforts were made to ‘professionalise’ the analysts. This paper is based on a detailed archival examination of the JIC’s documentary files. It will recount the reasons behind this organisational reform, what the changes entailed, and whether they were a success. The changes were immediately brought to bear with the intelligence assessments prior to the Soviet invasion of Czechoslovakia, something that the JIC failed to appreciate.

Keywords: intelligence, cold war history, analysis, united kingdom

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1522 Parameters of Validation Method of Determining Polycyclic Aromatic Hydrocarbons in Drinking Water by High Performance Liquid Chromatography

Authors: Jonida Canaj

Abstract:

A simple method of extraction and determination of fifteen priority polycyclic aromatic hydrocarbons (PAHs) from drinking water using high performance liquid chromatography (HPLC) has been validated with limits of detection (LOD) and limits of quantification (LOQ), method recovery and reproducibility, and other factors. HPLC parameters, such as mobile phase composition and flow standardized for determination of PAHs using fluorescent detector (FLD). PAH was carried out by liquid-liquid extraction using dichloromethane. Linearity of calibration curves was good for all PAH (R², 0.9954-1.0000) in the concentration range 0.1-100 ppb. Analysis of standard spiked water samples resulted in good recoveries between 78.5-150%(0.1ppb) and 93.04-137.47% (10ppb). The estimated LOD and LOQ ranged between 0.0018-0.98 ppb. The method described has been used for determination of the fifteen PAHs contents in drinking water samples.

Keywords: high performance liquid chromatography, HPLC, method validation, polycyclic aromatic hydrocarbons, PAHs, water

Procedia PDF Downloads 93
1521 One-Stage Conversion of Adjustable Gastric Band to One-Anastomosis Gastric Bypass Versus Sleeve Gastrectomy : A Single-Center Experience With a Short and Mid-term Follow-up

Authors: Basma Hussein Abdelaziz Hassan, Kareem Kamel, Philobater Bahgat Adly Awad, Karim Fahmy

Abstract:

Background: Laparoscopic adjustable gastric band was one of the most applied and common bariatric procedures in the last 8 years. However; the failure rate was very high, reaching approximately 60% of the patients not achieving the desired weight loss. Most patients sought another revisional surgery. In which, we compared two of the most common weight loss surgeries performed nowadays: the laparoscopic sleeve gastrectomy and laparoscopic one- anastomosis gastric bypass. Objective: To compare the weight loss and postoperative outcomes among patients undergoing conversion laparoscopic one-anastomosis gastric bypass (cOAGB) and laparoscopic sleeve gastrectomy (cSG) after a failed laparoscopic adjustable gastric band (LAGB). Patients and Methods: A prospective cohort study was conducted from June 2020 to June 2022 at a single medical center, which included 77 patients undergoing single-stage conversion to (cOAGB) vs (cSG). Patients were reassessed for weight loss, comorbidities remission, and post-operative complications at 6, 12, and 18 months. Results: There were 77 patients with failed LAGB in our study. Group (I) was 43 patients who underwent cOAGB and Group (II) was 34 patients who underwent cSG. The mean age of the cOAGB group was 38.58. While in the cSG group, the mean age was 39.47 (p=0.389). Of the 77 patients, 10 (12.99%) were males and 67 (87.01%) were females. Regarding Body mass index (BMI), in the cOAGB group the mean BMI was 41.06 and in the cSG group the mean BMI was 40.5 (p=0.042). The two groups were compared postoperative in relation to EBWL%, BMI, and the co-morbidities remission within 18 months follow-up. The BMI was calculated post-operative at three visits. After 6 months of follow-up, the mean BMI in the cOAGB group was 34.34, and the cSG group was 35.47 (p=0.229). In 12-month follow-up, the mean BMI in the cOAGB group was 32.69 and the cSG group was 33.79 (p=0.2). Finally, the mean BMI after 18 months of follow-up in the cOAGB group was 30.02, and in the cSG group was 31.79 (p=0.001). Both groups had no statistically significant values at 6 and 12 months follow-up with p-values of 0.229, and 0.2 respectively. However, patients who underwent cOAGB after 18 months of follow-up achieved lower BMI than those who underwent cSG with a statistically significant p-value of 0.005. Regarding EBWL% there was a statistically significant difference between the two groups. After 6 months of follow-up, the mean EBWL% in the cOAGB group was 35.9% and the cSG group was 33.14%. In the 12-month follow-up, the EBWL % mean in the cOAGB group was 52.35 and the cSG group was 48.76 (p=0.045). Finally, the mean EBWL % after 18 months of follow-up in the cOAGB group was 62.06 ±8.68 and in the cSG group was 55.58 ±10.87 (p=0.005). Regarding comorbidities remission; Diabetes mellitus remission was found in 22 (88%) patients in the cOAGB group and 10 (71.4%) patients in the cSG group with (p= 0.225). Hypertension remission was found in 20 (80%) patients in the cOAGB group and 14 (82.4%) patients in the cSG group with (p=1). In addition, dyslipidemia remission was found in 27(87%) patients in cOAGB group and 17(70%) patients in the cSG group with (p=0.18). Finally, GERD remission was found in about 15 (88.2%) patients in the cOAGB group and 6 (60%) patients in the cSG group with (p=0.47). There are no statistically significant differences between the two groups in the post-operative data outcomes. Conclusion: This study suggests that the conversion of LAGB to either cOAGB or cSG could be feasibly performed in a single-stage operation. cOAGB had a significant difference as regards the weight loss results than cSG among the mid-term follow-up. However, there is no significant difference in the postoperative complications and the resolution of the co-morbidities. Therefore, cOAGB could provide a reliable alternative but needs to be substantiated in future long-term studies.

Keywords: laparoscopic, gastric banding, one-anastomosis gastric bypass, Sleeve gastrectomy, revisional surgery, weight loss

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1520 Numerical Modeling and Prediction of Nanoscale Transport Phenomena in Vertically Aligned Carbon Nanotube Catalyst Layers by the Lattice Boltzmann Simulation

Authors: Seungho Shin, Keunwoo Choi, Ali Akbar, Sukkee Um

Abstract:

In this study, the nanoscale transport properties and catalyst utilization of vertically aligned carbon nanotube (VACNT) catalyst layers are computationally predicted by the three-dimensional lattice Boltzmann simulation based on the quasi-random nanostructural model in pursuance of fuel cell catalyst performance improvement. A series of catalyst layers are randomly generated with statistical significance at the 95% confidence level to reflect the heterogeneity of the catalyst layer nanostructures. The nanoscale gas transport phenomena inside the catalyst layers are simulated by the D3Q19 (i.e., three-dimensional, 19 velocities) lattice Boltzmann method, and the corresponding mass transport characteristics are mathematically modeled in terms of structural properties. Considering the nanoscale reactant transport phenomena, a transport-based effective catalyst utilization factor is defined and statistically analyzed to determine the structure-transport influence on catalyst utilization. The tortuosity of the reactant mass transport path of VACNT catalyst layers is directly calculated from the streaklines. Subsequently, the corresponding effective mass diffusion coefficient is statistically predicted by applying the pre-estimated tortuosity factors to the Knudsen diffusion coefficient in the VACNT catalyst layers. The statistical estimation results clearly indicate that the morphological structures of VACNT catalyst layers reduce the tortuosity of reactant mass transport path when compared to conventional catalyst layer and significantly improve consequential effective mass diffusion coefficient of VACNT catalyst layer. Furthermore, catalyst utilization of the VACNT catalyst layer is substantially improved by enhanced mass diffusion and electric current paths despite the relatively poor interconnections of the ion transport paths.

Keywords: Lattice Boltzmann method, nano transport phenomena, polymer electrolyte fuel cells, vertically aligned carbon nanotube

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1519 Classifying ERP Implementation’s Risks in Banking Sectors Based on Different Implementation Phases

Authors: Farnaz Farzadnia, Ahmad Alibabaei

Abstract:

Enterprise Resource Planning (ERP) systems are considered as complicated information systems. Many organizations failed implementing ERP systems because it is a very difficult, time-consuming and expensive process. Enterprise resource planning system is appropriate for organizations in all economic sectors. As banking is currently considered a non-typical area for ERP usage, there are very little studies on ERP implementation in banking. This paper presents a general risks taxonomy. In this research, after identifying implementation risks, a process quality management method has been applied to identify relations between risks of implementation ERP in banking sectors and implementation phases. Oracle application implementation method titled as AIM used in this research for classifying the risks. These findings will help managers to develop better strategies for supervising and controlling ERP implementation projects.

Keywords: AIM implementation, bank, enterprise resource planning, risk, process quality management method

Procedia PDF Downloads 528