Search results for: Operation Research.
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 7044

Search results for: Operation Research.

6864 Dual Band Fractal Antenna for Wireless Sensor Network Application

Authors: M. Shanmugapriya, M. A. Maluk Mohamed, J. William

Abstract:

A wireless sensor network (WSN) is a collection of sensor nodes organized into a cooperative network. These nodes communicate through a wireless antenna. Reduction in physical size and multiband operation is an important requirement of WSN antenna. Fractal antenna is used for miniaturization and multiband operation. The self-similar or self-affine and space filling property of fractal geometry increases the effective electrical length of the antenna, reduces the size and make them frequency independent. This paper elaborates on Dual band fractal antenna with Coplanar Waveguide (CPW) feed for WSN. The proposed antenna is designed on a FR4 substrate with the dimension of 27mm x 28.5mm x 1.6mm, resonates at 2.4GHz and 5.2GHz with a return loss less than -10dB. The design and simulation process is carried out using IE3D simulation software. The simulated and measured results are found in good agreement.

Keywords: CPW, Fractal, Iterations, Miniaturization, Space filling, Self Similar, WSN, WLAN.

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6863 DNA Computing for an Absolute 1-Center Problem: An Evolutionary Approach

Authors: Zuwairie Ibrahim, Yusei Tsuboi, Osamu Ono, Marzuki Khalid

Abstract:

Deoxyribonucleic Acid or DNA computing has emerged as an interdisciplinary field that draws together chemistry, molecular biology, computer science and mathematics. Thus, in this paper, the possibility of DNA-based computing to solve an absolute 1-center problem by molecular manipulations is presented. This is truly the first attempt to solve such a problem by DNA-based computing approach. Since, part of the procedures involve with shortest path computation, research works on DNA computing for shortest path Traveling Salesman Problem, in short, TSP are reviewed. These approaches are studied and only the appropriate one is adapted in designing the computation procedures. This DNA-based computation is designed in such a way that every path is encoded by oligonucleotides and the path-s length is directly proportional to the length of oligonucleotides. Using these properties, gel electrophoresis is performed in order to separate the respective DNA molecules according to their length. One expectation arise from this paper is that it is possible to verify the instance absolute 1-center problem using DNA computing by laboratory experiments.

Keywords: DNA computing, operation research, 1-center problem.

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6862 Analysis of Gas Disturbance Characteristics in Lunar Sample Storage

Authors: Lv Shizeng, Han Xiao, Zhang Yi, Ding Wenjing

Abstract:

The lunar sample storage device is mainly used for the preparation of the lunar samples, observation, physical analysis and other work. The lunar samples and operating equipment are placed directly inside the storage device. The inside of the storage device is a high purity nitrogen environment to ensure that the sample is not contaminated by the Earth's environment. In order to ensure that the water and oxygen indicators in the storage device meet the sample requirements, a dynamic gas cycle is required between the storage device and the external purification equipment. However, the internal gas disturbance in the storage device can affect the operation of the sample. In this paper, the storage device model is established, and the tetrahedral mesh is established by Tetra/Mixed method. The influence of different inlet position and gas flow on the internal flow field disturbance is calculated, and the disturbed flow area should be avoided during the sampling operation.

Keywords: Lunar samples, gas disturbance, storage device, characteristic analysis.

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6861 Exploring SSD Suitable Allocation Schemes Incompliance with Workload Patterns

Authors: Jae Young Park, Hwansu Jung, Jong Tae Kim

Abstract:

In the Solid-State-Drive (SSD) performance, whether the data has been well parallelized is an important factor. SSD parallelization is affected by allocation scheme and it is directly connected to SSD performance. There are dynamic allocation and static allocation in representative allocation schemes. Dynamic allocation is more adaptive in exploiting write operation parallelism, while static allocation is better in read operation parallelism. Therefore, it is hard to select the appropriate allocation scheme when the workload is mixed read and write operations. We simulated conditions on a few mixed data patterns and analyzed the results to help the right choice for better performance. As the results, if data arrival interval is long enough prior operations to be finished and continuous read intensive data environment static allocation is more suitable. Dynamic allocation performs the best on write performance and random data patterns.

Keywords: Dynamic allocation, NAND Flash based SSD, SSD parallelism, static allocation.

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6860 Parallel Double Splicing on Iso-Arrays

Authors: V. Masilamani, D.K. Sheena Christy, D.G. Thomas

Abstract:

Image synthesis is an important area in image processing. To synthesize images various systems are proposed in the literature. In this paper, we propose a bio-inspired system to synthesize image and to study the generating power of the system, we define the class of languages generated by our system. We call image as array in this paper. We use a primitive called iso-array to synthesize image/array. The operation is double splicing on iso-arrays. The double splicing operation is used in DNA computing and we use this to synthesize image. A comparison of the family of languages generated by the proposed self restricted double splicing systems on iso-arrays with the existing family of local iso-picture languages is made. Certain closure properties such as union, concatenation and rotation are studied for the family of languages generated by the proposed model.

Keywords: DNA computing, splicing system, iso-picture languages, iso-array double splicing system, iso-array self splicing.

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6859 A Review on Marine Search and Rescue Operations Using Unmanned Aerial Vehicles

Authors: S. P. Yeong, L. M. King, S. S. Dol

Abstract:

There have been rigorous research and development of unmanned aerial vehicles in the field of search and rescue (SAR) operation recently. UAVs reduce unnecessary human risks while assisting rescue efforts through aerial imagery, topographic mapping and emergency delivery. The application of UAVs in offshore and nearshore marine SAR missions is discussed in this paper. Projects that integrate UAV technology into their systems are introduced to highlight the great advantages and capabilities of UAVs. Scenarios where UAVs could provide invaluable assistance are also suggested.

Keywords: Marine SAR, nearshore, offshore, search and rescue, UAS, UAV.

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6858 Solid Circulation Rate and Gas Leakage Measurements in an Interconnected Bubbling Fluidized Beds

Authors: Ho-Jung Ryu, Seung-Yong Lee, Young Cheol Park, Moon-Hee Park

Abstract:

Two-interconnected fluidized bed systems are widely used in various processes such as Fisher-Tropsch, hot gas desulfurization, CO2 capture-regeneration with dry sorbent, chemical-looping combustion, sorption enhanced steam methane reforming, chemical-looping hydrogen generation system, and so on. However, most of two-interconnected fluidized beds systems require riser and/or pneumatic transport line for solid conveying and loopseals or seal-pots for gas sealing, recirculation of solids to the riser, and maintaining of pressure balance. The riser (transport bed) is operated at the high velocity fluidization condition and residence times of gas and solid in the riser are very short. If the reaction rate of catalyst or sorbent is slow, the riser can not ensure sufficient contact time between gas and solid and we have to use two bubbling beds for each reaction to ensure sufficient contact time. In this case, additional riser must be installed for solid circulation. Consequently, conventional two-interconnected fluidized bed systems are very complex, large, and difficult to operate. To solve these problems, a novel two-interconnected fluidized bed system has been developed. This system has two bubbling beds, solid injection nozzles, solid conveying lines, and downcomers. In this study, effects of operating variables on solid circulation rate, gas leakage between two beds have been investigated in a cold mode two-interconnected fluidized bed system. Moreover, long-term operation of continuous solid circulation up to 60 hours has been performed to check feasibility of stable operation.

Keywords: Fluidized bed, Gas leakage, Long-term operation, Solid circulation.

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6857 A Specification-Based Approach for Retrieval of Reusable Business Component for Software Reuse

Authors: Meng Fanchao, Zhan Dechen, Xu Xiaofei

Abstract:

Software reuse can be considered as the most realistic and promising way to improve software engineering productivity and quality. Automated assistance for software reuse involves the representation, classification, retrieval and adaptation of components. The representation and retrieval of components are important to software reuse in Component-Based on Software Development (CBSD). However, current industrial component models mainly focus on the implement techniques and ignore the semantic information about component, so it is difficult to retrieve the components that satisfy user-s requirements. This paper presents a method of business component retrieval based on specification matching to solve the software reuse of enterprise information system. First, a business component model oriented reuse is proposed. In our model, the business data type is represented as sign data type based on XML, which can express the variable business data type that can describe the variety of business operations. Based on this model, we propose specification match relationships in two levels: business operation level and business component level. In business operation level, we use input business data types, output business data types and the taxonomy of business operations evaluate the similarity between business operations. In the business component level, we propose five specification matches between business components. To retrieval reusable business components, we propose the measure of similarity degrees to calculate the similarities between business components. Finally, a business component retrieval command like SQL is proposed to help user to retrieve approximate business components from component repository.

Keywords: Business component, business operation, business data type, specification matching.

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6856 System Reliability by Prediction of Generator Output and Losses in a Competitive Energy Market

Authors: Perumal Nallagownden, Ravindra N. Mukerjee, Syafrudin Masri

Abstract:

In a competitive energy market, system reliability should be maintained at all times. Power system operation being of online in nature, the energy balance requirements must be satisfied to ensure reliable operation the system. To achieve this, information regarding the expected status of the system, the scheduled transactions and the relevant inputs necessary to make either a transaction contract or a transmission contract operational, have to be made available in real time. The real time procedure proposed, facilitates this. This paper proposes a quadratic curve learning procedure, which enables a generator-s contribution to the retailer demand, power loss of transaction in a line at the retail end and its associated losses for an oncoming operating scenario to be predicted. Matlab program was used to test in on a 24-bus IEE Reliability Test System, and the results are found to be acceptable.

Keywords: Deregulation, learning coefficients, reliability, prediction, competitive energy market.

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6855 Phishing Attacks Facilitated by Open-Source Intelligence

Authors: Urva Maryam

Abstract:

Private data are more often breached by clever social engineering rather than exploiting technical vulnerabilities in the systems. Complete information security requires good data safety practices to go along with technical solutions. Hackers often begin their operation by simply sending spoofed emails or fraudulent URLs to their targets and trick them into providing sensitive information such as passwords or bank account details. This technique is called phishing. Phishing attacks can be launched on email addresses, open ports and unsecured web browsers. This study uses quantitative method of research to execute phishing experiments on the participants to test their response to the phishing emails. These experiments were run on Kali Linux distribution which came bundled with multiple open-source intelligence (OSINT) tools that were used in the study. The aim of this research is to see how successful phishing attacks can be launched using OSINT and to test the response of people to spoofed emails.

Keywords: OSINT, phishing, spear phishing, email spoofing, theHarvester, Maltego.

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6854 Changes in the Research of Crisis

Authors: M. Mikusova

Abstract:

Thanks to the interdisciplinary nature of crises, the position of researchers in that field is rather difficult. Very often the traditional methods of research cannot be applied there. The article is aimed at the changes in crises research. It describes the substance of individual changes and emphasizes the shift in research approaches to the crisis.

Keywords: crisis, change, research

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6853 A Novel Approach of Power Transformer Diagnostic Using 3D FEM Parametrical Model

Authors: M. Brandt, A. Peniak, J. Makarovič, P. Rafajdus

Abstract:

This paper deals with a novel approach of power transformers diagnostics. This approach identifies the exact location and the range of a fault in the transformer and helps to reduce operation costs related to handling of the faulty transformer, its disassembly and repair. The advantage of the approach is a possibility to simulate healthy transformer and also all faults, which can occur in transformer during its operation without its disassembling, which is very expensive in practice. The approach is based on creating frequency dependent impedance of the transformer by sweep frequency response analysis measurements and by 3D FE parametrical modeling of the fault in the transformer. The parameters of the 3D FE model are the position and the range of the axial short circuit. Then, by comparing the frequency dependent impedances of the parametrical models with the measured ones, the location and the range of the fault is identified. The approach was tested on a real transformer and showed high coincidence between the real fault and the simulated one.

Keywords: Fault, finite element method, parametrical model of transformer, sweep frequency response analysis, transformer.

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6852 Sorptive Storage of Natural Gas on Molecular Sieves: Dynamic Investigation

Authors: S. Al-Asheh, K. Al-Emadi

Abstract:

In recent years, there have been attempts to store natural gas in adsorptive form. This is called adsorptive natural gas, or ANG. The problem with this technology is the low sorption capacity. The purpose is to achieve compressed natural gas (CNG) capacity of 230 V/V. Further research is required to achieve such target. Several research studies have been performed with this target; through either the modification or development of new sorbents or the optimization of the operation sorption process itself. In this work, storage of methane on molecular sieves 5A and 13X was studied on dry basis, and on wet basis to certain extent. The temperature and the pressure dynamics were investigated. The results indicated that regardless of the charge pressure, the time for the peak temperature during the methane charge process is always the same. This can be used as a characteristic of the adsorbent. The total achieved deliveries using molecular sieves were much lower than that of activated carbons; 53.0 V/V for the case of 13X molecular sieves and 43 V/V for the case of 5A molecular sieves, both at 2oC and 4 MPa (580 psi). Investigation of charge pressure dynamic using wet molecular sieves at 2oC and a mass ratio of 0.5, revealed slowness of the process and unexpected behavior.

Keywords: Methane, Molecular sieves, Adsorption, Delivery, Storage.

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6851 Combustion Improvements by C4/C5 Bio-Alcohol Isomer Blended Fuels Combined with Supercharging and EGR in a Diesel Engine

Authors: Yasufumi Yoshimoto, Enkhjargal Tserenochir, Eiji Kinoshita, Takeshi Otaka

Abstract:

Next generation bio-alcohols produced from non-food based sources like cellulosic biomass are promising renewable energy sources. The present study investigates engine performance, combustion characteristics, and emissions of a small single cylinder direct injection diesel engine fueled by four kinds of next generation bio-alcohol isomer and diesel fuel blends with a constant blending ratio of 3:7 (mass). The tested bio-alcohol isomers here are n-butanol and iso-butanol (C4 alcohol), and n-pentanol and iso-pentanol (C5 alcohol). To obtain simultaneous reductions in NOx and smoke emissions, the experiments employed supercharging combined with EGR (Exhaust Gas Recirculation). The boost pressures were fixed at two conditions, 100 kPa (naturally aspirated operation) and 120 kPa (supercharged operation) provided with a roots blower type supercharger. The EGR rates were varied from 0 to 25% using a cooled EGR technique. The results showed that both with and without supercharging, all the bio-alcohol blended diesel fuels improved the trade-off relation between NOx and smoke emissions at all EGR rates while maintaining good engine performance, when compared with diesel fuel operation. It was also found that regardless of boost pressure and EGR rate, the ignition delays of the tested bio-alcohol isomer blends are in the order of iso-butanol > n-butanol > iso-pentanol > n-pentanol. Overall, it was concluded that, except for the changes in the ignition delays the influence of bio-alcohol isomer blends on the engine performance, combustion characteristics, and emissions are relatively small.

Keywords: Alternative fuel,  Butanol, Diesel engine, EGR, Next generation bio-alcohol isomer blended fuel, Pentanol, Supercharging.

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6850 Improving the LDMOS Temperature Compensation Bias Circuit to Optimize Back-Off

Authors: Antonis Constantinides, Christos Yiallouras, Christakis Damianou

Abstract:

The application of today's semiconductor transistors in high power UHF DVB-T linear amplifiers has evolved significantly by utilizing LDMOS technology. This fact provides engineers with the option to design a single transistor signal amplifier which enables output power and linearity that was unobtainable previously using bipolar junction transistors or later type first generation MOSFETS. The quiescent current stability in terms of thermal variations of the LDMOS guarantees a robust operation in any topology of DVB-T signal amplifiers. Otherwise, progressively uncontrolled heat dissipation enhancement on the LDMOS case can degrade the amplifier’s crucial parameters in regards to the gain, linearity and RF stability, resulting in dysfunctional operation or a total destruction of the unit. This paper presents one more sophisticated approach from the traditional biasing circuits used so far in LDMOS DVB-T amplifiers. It utilizes a microprocessor control technology, providing stability in topologies where IDQ must be perfectly accurate.

Keywords: Amplifier, DVB-T, LDMOS, MOSFETS.

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6849 Silicon-based Low-Power Reconfigurable Optical Add-Drop Multiplexer (ROADM)

Authors: Junfeng Song, Xianshu Luo, Qing Fang, Lianxi Jia, Xiaoguang Tu, Tsung-Yang Liow, Mingbin Yu, Guo-Qiang Lo

Abstract:

We demonstrate a 1×4 coarse wavelength division-multiplexing (CWDM) planar concave grating multiplexer/demultiplexer and its application in re-configurable optical add/drop multiplexer (ROADM) system in silicon-on-insulator substrate. The wavelengths of the demonstrated concave grating multiplexer align well with the ITU-T standard. We demonstrate a prototype of ROADM comprising two such concave gratings and four wide-band thermo-optical MZI switches. Undercut technology which removes the underneath silicon substrate is adopted in optical switches in order to minimize the operation power. For all the thermal heaters, the operation voltage is smaller than 1.5 V, and the switch power is ~2.4 mW. High throughput pseudorandom binary sequence (PRBS) data transmission with up to 100 Gb/s is demonstrated, showing the high-performance ROADM functionality.

Keywords: ROADM, Optical switch, low power consumption, Integrated devices.

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6848 The Study of Applying Models: House, Temple and School for Sufficiency Development to Participate in ASEAN Economic Community: A Case Study of Trimitra Temple (China Town) Bangkok, Thailand

Authors: Saowapa Phaithayawat

Abstract:

The purposes of this study are 1) to study the impact of the 3-community-core model: House (H), Temple (T), and School (S) with the co-operation of official departments on community development to ASEAN economic community involvement and 2) to study the procedures and extension of the model. The research which is a qualitative research is based on the formal and informal interviews. Local people in a community are observed. Group interview is, also, operated by executors and cooperators in the school in the community. In terms of social and cultural dimension, the 3-community-core model consisting of house, temple and school is the base of Thai cultures bringing about understanding, happiness and unity to the community. The result of this research is that the official departments in accompanied with this model developers cooperatively work together in the community to support such factors as budget, plan, activities. Moreover, the need of community, and the continual result to sustain the community are satisfied by the model implementation. In terms of the procedures of the model implementation, executors and co-operators can work, coordinate, think, and launch their public relation altogether. Concerning the model development, this enables the community to achieve its goal to prepare the community’s readiness for ASEAN Economic Community involvement.

Keywords: ASEAN Economic Community, Community Development.

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6847 Distillation Monitoring and Control using LabVIEW and SIMULINK Tools

Authors: J. Fernandez de Canete, P. Del Saz Orozco, S. Gonzalez-Perez

Abstract:

LabVIEW and SIMULINK are two most widely used graphical programming environments for designing digital signal processing and control systems. Unlike conventional text-based programming languages such as C, Cµ and MATLAB, graphical programming involves block-based code developments, allowing a more efficient mechanism to build and analyze control systems. In this paper a LabVIEW environment has been employed as a graphical user interface for monitoring the operation of a controlled distillation column, by visualizing both the closed loop performance and the user selected control conditions, while the column dynamics has been modeled under the SIMULINK environment. This tool has been applied to the PID based decoupled control of a binary distillation column. By means of such integrated environments the control designer is able to monitor and control the plant behavior and optimize the response when both, the quality improvement of distillation products and the operation efficiency tasks, are considered.

Keywords: Distillation control, software tools, SIMULINKLabVIEWinterface.

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6846 A Reinforcement Learning Approach for Evaluation of Real-Time Disaster Relief Demand and Network Condition

Authors: Ali Nadi, Ali Edrissi

Abstract:

Relief demand and transportation links availability is the essential information that is needed for every natural disaster operation. This information is not in hand once a disaster strikes. Relief demand and network condition has been evaluated based on prediction method in related works. Nevertheless, prediction seems to be over or under estimated due to uncertainties and may lead to a failure operation. Therefore, in this paper a stochastic programming model is proposed to evaluate real-time relief demand and network condition at the onset of a natural disaster. To address the time sensitivity of the emergency response, the proposed model uses reinforcement learning for optimization of the total relief assessment time. The proposed model is tested on a real size network problem. The simulation results indicate that the proposed model performs well in the case of collecting real-time information.

Keywords: Disaster management, real-time demand, reinforcement learning, relief demand.

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6845 Experimental Study on the Hysteresis Properties in Operation of Vertical Axis Wind Turbines

Authors: Ching-Huei Lin, Yao-Pang Hsu, M. Z. Dosaev, Yu. D. Selyutskii, L. A. Klimina

Abstract:

Hysteresis phenomenon has been observed in the operations of both horizontal-axis and vertical-axis wind turbines (HAWTs and VAWTs). In this study, wind tunnel experiments were applied to investigate the characters of hysteresis phenomena between the angular speed and the external resistance of electrical loading during the operation of a Darrieus type VAWT. Data of output voltage, output current, angular speed of wind turbine under different wind speeds are measured and analyzed. Results show that the range of external resistance changes with the wind speed. The range decreases as the wind speed increases following an exponential decay form. Experiments also indicate that the maximum output power of wind turbines is always inside the range where hysteresis happened. These results provide an important reference to the design of output control system of wind turbines.

Keywords: Hysteresis phenomenon, Angular speed, Range ofexternal resistance

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6844 Public Private Partnership for Infrastructure Projects: Mapping the Key Risks

Authors: Julinda Keçi

Abstract:

In many countries, governments have been promoting the involvement of private sector entities to enter into long-term agreements for the development and delivery of large infrastructure projects, with a focus on overcoming the limitations upon public fund of the traditional approach. The involvement of private sector through public private partnerships (PPP) brings in new capital investments, value for money and additional risks to handle. Worldwide research studies have shown that an objective, systematic, reliable and useroriented risk assessment process and an optimal allocation mechanism among different stakeholders is crucial to the successful completion. In this framework, this paper, which is the first stage of a research study, aims to identify the main risks for the delivery of PPP projects. A review of cross-countries research projects and case studies was performed to map the key risks affecting PPP infrastructure delivery. The matrix of mapping offers a summary of the frequency of factors, clustered in eleven categories: construction, design, economic, legal, market, natural, operation, political, project finance, project selection and relationship. Results will highlight the most critical risk factors, and will hopefully assist the project managers in directing the managerial attention in the further stages of risk allocation.

Keywords: Construction, infrastructure, public private partnerships, risks.

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6843 Numerical Analysis of Fractured Process in Locomotive Steel Wheels

Authors: J. Alizadeh K., R. S. Ashofteh, A. Asadi Lari

Abstract:

Railway vehicle wheels are designed to operate in harsh environments and to withstand high hydrostatic contact pressures. This situation may result in critical circumstances, in particular wheel breakage. This paper presents a time history of a series of broken wheels during a time interval [2007-2008] belongs to locomotive fleet on Iranian Railways. Such fractures in locomotive wheels never reported before. Due to the importance of this issue, a research study has been launched to find the potential reasons of this problem. The authors introduce a FEM model to indicate how and where the wheels could have been affected during their operation. Then, the modeling results are presented and discussed in detail.

Keywords: Crack, fatigue, FE analysis, wheel.

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6842 Automated Driving Deep Neural Network Model Accuracy and Performance Assessment in a Simulated Environment

Authors: David Tena-Gago, Jose M. Alcaraz Calero, Qi Wang

Abstract:

The evolution and integration of automated vehicles have become more and more tangible in recent years. State-of-the-art technological advances in the field of camera-based Artificial Intelligence (AI) and computer vision greatly favor the performance and reliability of Advanced Driver Assistance System (ADAS), leading to a greater knowledge of vehicular operation and resembling the human behaviour. However, the exclusive use of this technology still seems insufficient to control the vehicular operation at 100%. To reveal the degree of accuracy of the current camera-based automated driving AI modules, this paper studies the structure and behavior of one of the main solutions in a controlled testing environment. The results obtained clearly outline the lack of reliability when using exclusively the AI model in the perception stage, thereby entailing using additional complementary sensors to improve its safety and performance.

Keywords: Accuracy assessment, AI-Driven Mobility, Artificial Intelligence, automated vehicles.

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6841 Simulating Flow Transients in Conveying Pipeline Systems by Rigid Column and Full Elastic Methods: Pump Combined with Air Chamber

Authors: I. Abuiziah, A. Oulhaj, K. Sebari, D. Ouazar, A. A. Saber

Abstract:

In water pipeline systems, the flow control is an integrated part of the operation, for instance, opening and closing the valves, starting and stopping the pumps, when these operations very quickly performed, they shall cause the hydraulic transient phenomena, which may cause pump and, valve failures and catastrophic pipe ruptures. Fluid transient analysis is one of the more challenging and complicated flow problems in the design and the operation of water pipeline systems. Transient control has become an essential requirement for ensuring safe operation of water pipeline systems. An accurate analysis and suitable protection devices should be used to protect water pipeline systems. The fourth-order Runge-Kutta method has been used to solve the dynamic and continuity equations in the rigid column method, while the characteristics method used to solve these equations in the full elastic methods. This paper presents the problem of modeling and simulating of transient phenomena in conveying pipeline systems based on the rigid column and full elastic methods. Also, it provides the influence of using the protection devices to protect the pipeline systems from damaging due to the gain pressure which occur in the transient state. The results obtained provide that the model is an efficient tool for flow transient analysis and provide approximately identical results by using these two methods. Moreover; using the closed surge tank reduces the unfavorable effects of transients.

Keywords: Flow transient, Pipeline, Air chamber, Numerical model, Protection devices, Elastic method, Rigid column method.

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6840 Effect of Nitrogen Gaseous Plasma on Cotton Fabric Dyed with Reactive Yellow105

Authors: Mohammad Mirjalili, Hamid Akbarpour

Abstract:

In this work, a bleached well cotton sample was dyed with reactive yellow105 dye and subsequently, the dyed sample was exposed to the plasma condition containing Nitrogen gas at 1 and 5 minutes of plasma exposure time, respectively. The effect of plasma on surface morphology fabric was studied by Scanning Electronic Microscope (SEM). CIELab, K/S, and %R of samples (treated and untreated samples) were measured by a reflective spectrophotometer, and consequently, the experiments show that the sample dyed with Reactive yellow 105 after being washed, with the increase in the operation time of plasma, its dye fastness decreases. In addition, the increase in plasma operation time at constant pressure would increase the destructing effect on the surface morphology of samples dyed with reactive yellow105.

Keywords: Cotton fabric, cold nitrogen plasma, reflective spectrophotometer, electronic scanning microscope (SEM), reactive yellow105 dye.

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6839 RBF Modelling and Optimization Control for Semi-Batch Reactors

Authors: Magdi M. Nabi, Ding-Li Yu

Abstract:

This paper presents a neural network based model predictive control (MPC) strategy to control a strongly exothermic reaction with complicated nonlinear kinetics given by Chylla-Haase polymerization reactor that requires a very precise temperature control to maintain product uniformity. In the benchmark scenario, the operation of the reactor must be guaranteed under various disturbing influences, e.g., changing ambient temperatures or impurity of the monomer. Such a process usually controlled by conventional cascade control, it provides a robust operation, but often lacks accuracy concerning the required strict temperature tolerances. The predictive control strategy based on the RBF neural model is applied to solve this problem to achieve set-point tracking of the reactor temperature against disturbances. The result shows that the RBF based model predictive control gives reliable result in the presence of some disturbances and keeps the reactor temperature within a tight tolerance range around the desired reaction temperature.

Keywords: Chylla-Haase reactor, RBF neural network modelling, model predictive control.

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6838 Effect of COD Loading Rate on Hydrogen Production from Alcohol Wastewater

Authors: Patcharee Intanoo, Jittipan Chavadej, Sumaeth Chavadej

Abstract:

The objective of this study was to investigate hydrogen production from alcohol wastewater by anaerobic sequencing batch reactor (ASBR) under thermophillic operation. The ASBR unit used in this study had a liquid holding volume of 4 L and was operated at 6 cycles per day. The seed sludge taken from an upflow anaerobic sludge blanket unit treating the same wastewater was boiled at 95 °C for 15 min before being fed to the ASBR unit. The ASBR system was operated at different COD loading rates at a thermophillic temperature (55 °C), and controlled pH of 5.5. When the system was operated under optimum conditions (providing maximum hydrogen production performance) at a feed COD of 60 000 mg/l, and a COD loading rate of 68 kg/m3 d, the produced gas contained 43 % H2 content in the produced gas. Moreover, the hydrogen yield and the specific hydrogen production rate (SHPR) were 130 ml H2/g COD removed and 2100 ml H2/l d, respectively.

Keywords: Biohydrogen, Alcohol wastewater, Anaerobic sequencing batch reactor (ASBR), Thermophillic operation

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6837 A Review of Critical Success Factor in Building Maintenance Management Practice for University Sector

Authors: S.H. Zulkarnain, E.M.A Zawawi, M.Y. A. Rahman, N.K.F. Mustafa

Abstract:

Building maintenance plays an important role among other activities in building operation. Building defect and damages are part of the building maintenance 'bread and butter' as their input indicated in the building inspection is very much justified, particularly as to determine the building performance. There will be no escape route or short cut from building maintenance work. This study attempts to identify a competitive performance that translates the Critical Success Factor achievements and satisfactorily meet the university-s expectation. The quality and efficiency of maintenance management operation of building depends, to some extent, on the building condition information, the expectation from the university sector and the works carried out for each maintenance activity. This paper reviews the critical success factor in building maintenance management practice for university sectors from four (4) perspectives which include (1) customer (2) internal processes (3) financial and (4) learning and growth perspective. The enhancement of these perspectives is capable to reach the maintenance management goal for a better living environment in university campus.

Keywords: Building maintenance, Critical Success Factor, Management, University

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6836 Methods for Better Assessment of Fatigue and Deterioration in Bridges and Other Steel or Concrete Constructions

Authors: J. Menčík, B. Culek, Jr., L. Beran, J. Mareš

Abstract:

Large metal and concrete structures suffer by various kinds of deterioration, and accurate prediction of the remaining life is important. This paper informs about two methods for its assessment. One method, suitable for steel bridges and other constructions exposed to fatigue, monitors the loads and damage accumulation using information systems for the operation and the finite element model of the construction. In addition to the operation load, the dead weight of the construction and thermal stresses can be included into the model. The second method is suitable for concrete bridges and other structures, which suffer by carbonatation and other degradation processes, driven by diffusion. The diffusion constant, important for the prediction of future development, can be determined from the depth-profile of pH, obtained by pH measurement at various depths. Comparison with measurements on real objects illustrates the suitability of both methods.

Keywords: Bridges, carbonatation, concrete, diagnostics, fatigue, life prediction, monitoring, railway, simulation, structures.

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6835 Design Techniques and Implementation of Low Power High-Throughput Discrete Wavelet Transform Tilters for JPEG 2000 Standard

Authors: Grigorios D. Dimitroulakos, N. D. Zervas, N. Sklavos, Costas E. Goutis

Abstract:

In this paper, the implementation of low power, high throughput convolutional filters for the one dimensional Discrete Wavelet Transform and its inverse are presented. The analysis filters have already been used for the implementation of a high performance DWT encoder [15] with minimum memory requirements for the JPEG 2000 standard. This paper presents the design techniques and the implementation of the convolutional filters included in the JPEG2000 standard for the forward and inverse DWT for achieving low-power operation, high performance and reduced memory accesses. Moreover, they have the ability of performing progressive computations so as to minimize the buffering between the decomposition and reconstruction phases. The experimental results illustrate the filters- low power high throughput characteristics as well as their memory efficient operation.

Keywords: Discrete Wavelet Transform; JPEG2000 standard; VLSI design; Low Power-Throughput-optimized filters

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