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Adaptive Science and Technology (ICAST), 2011 3rd IEEE International Conference

Date 24-26 Nov. 2011

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Displaying Results 1 - 25 of 34
  • Real Time SMS-Based hashing scheme for securing financial transactions on ATM systems

    Page(s): 1 - 6
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1021 KB) |  | HTML iconHTML  

    One noticeable dividend of the adoption and use of Automated Teller Machine (ATM) by Nigerian banks dating back to the early 1990s is the ease of access to cash by bank customers. However, incidences of ATM frauds has emerged as a limiting factor resulting in a decline adoption for transacting banking businesses. Fraudsters now employ different means to hunt for user's Personal Identification Numbers (PIN) in order to defraud unsuspecting customers. Existing measures adopted by financial institutions require ATM card holders to optionally subscribe to financial transactions message alerts through Short Message Services (SMS) (debit and credit transactions) and the use of posters pasted in banking halls to warn customers on the need to protect PIN numbers from unauthorized users. These measures are purely informative and do not adequately deal with the problems in real time. In this paper, we introduce a Real Time Instructive SMS-Based scheme called MophTem scheme which compels all customers to subscribe to SMS alerts as a basis for initiating transactions on their account. The bank generates a hash code using the customer PIN number and phone number. The generated hash key is then used to decrypt messages requesting for transactions from the customer. The intention is to provide additional security layer and fortify existing PIN access thus safeguarding customer accounts and account information. View full abstract»

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  • Mobi4D: A next generation service delivery platform for mobile government services: An African perspective

    Page(s): 15 - 20
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (611 KB) |  | HTML iconHTML  

    The proliferation of mobile devices now ubiquitous to virtually everyone in Africa has made it absolutely easy to get across to every user. Innovative ideas have quickly developed around mobile devices as well as technology surrounding it and while the earliest uses were born out of necessity, the current technology is harnessing the power of mobile devices to support and propel citizen engagement in democracy. With its Mobi4D platform project, the CSIR is pioneering the utilization of mobile devices to fully implement mobile government application with the aim of significantly improving the quality of service delivered to the citizens of South Africa. In this paper, we report the current development around the Mobi4D platform and discuss from the view point of opportunities it presents for mobile government. Demos of some of the pilot services being developed on Mobi4D are also presented showing how such platform can help address challenges faced in the government sector. View full abstract»

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  • Validation of channels stability in multiple wavelength Brillouin-erbium fiber laser

    Page(s): 21 - 25
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (271 KB) |  | HTML iconHTML  

    A multiple wavelength Brillouin/erbium fiber laser that generated six output channels at maximum pumping powers is presented. The laser is configured to allow uni-directional flow of both the Brillouin pump and the Brillouin Stokes signals through the Erbium doped fiber amplifier. Stability studies on the generated channels buttressed the fact that the proposed laser has met the stringent requirement of power stability and precision channel spacing in order to be deployed to support the DWDM systems. At Brillouin pump power of 2 mW and 1480 nm laser pump power of 130 mW, the wavelength of the first channel has not shifted over an observation period of one hour. The other channels recorded average wavelength shifts of 0.002 nm. Over the same observation period, the first channel records a power fluctuations of only 0.03 dB. View full abstract»

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  • A formal theory for web-based control for GSM Quality-of-Service

    Page(s): 26 - 30
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (259 KB) |  | HTML iconHTML  

    The need for effective web-based control ontology for GSM Quality-of-Service (QoS) demands the availability of a formal theory that allows for a dynamic interaction among the parties concerned. This dynamic control ontology follows a three-tier dynamic architecture that is void of total dependence on the information from the providers and also employs a feedback mechanism from the actual users of the services. This work proposes a formal model for Dynamic Control Ontology that will aid in providing efficient quality control measures over GSM services. Identified concepts and relationships were considered as basic facts and inferences around these concepts were defined. First-Order Logic, due to its expressivity was considered as the appropriate representational language for this formal model. This work would provide the platform for efficient reasoning and proofs of logical consequences that serve as answers to questions raised by government during its policy making, telecommunication companies when making findings on how to compete and take management decisions and subscribers in their choice of network. This model is expected to assist in ensuring effective quality, affordability of telephone services, as well as increased geographical spread of communication services in Nigeria. View full abstract»

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  • Towards an adaptive multi-agent architecture for association rule mining in distributed databases

    Page(s): 31 - 36
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (233 KB) |  | HTML iconHTML  

    Association rule mining, which is a data mining technique, finds interesting association or correlation relationships among a large set of data items. Current association rule mining tasks can only be accomplished successfully only in a distributed setting, which will require integration of knowledge generated from the multiple data sites. Most existing architectures for mining in such circumstances require massive movement of data resulting in high communication overheads leading to slow response time. These challenges are heightened when we have extremely large data sizes in multiple heterogeneous sites. Moreover, most existing algorithms and architectures are only moderately suitable for real-world scenarios. There is therefore an urgent need for improved architectures that will explore the capabilities of software agents' paradigms in order to improve on the existing systems. This work therefore introduces an adaptive architectural framework that mines association rules across multiple data sites, and more importantly the architecture adapts to changes in the updated database giving special considerations to the incremental database with the X-Apriori algorithm. The results integration agent also adapts to changes in the results sites considering the size of the agents; size of intermediate results; bandwidth, and other computational resources at the data servers. The proposed system promises to reduce communication and interpretation costs, improve autonomy and efficiency of distributed association rule mining tasks. View full abstract»

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  • Essential parameters of Space-Borne Oscillators that ensures performance of Satellite-Based Augmentation System

    Page(s): 42 - 50
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1058 KB) |  | HTML iconHTML  

    Satellite-Based Augmentation System (SBAS) arose from the need to provide continuity, availability, integrity and accuracy of global positioning signals to eliminate errors and compensate for discrepancies associated with GPS signals and other navigation systems. The NIGCOMSAT-1R Project is the insurance replacement of the NIGCOMSAT-1 satellite, which was de-orbited on 10th of November 2008 due to an irreparable single point of failure on-board the satellite. The NigComSat-1R Navigation (L-band) payload is a Space Based Augmentation System meant to provide a Navigation Overlay Service (NOS) similar to the European Geostationary Navigation Overlay Service (EGNOS). The paper seeks to examine some of humankind's triumphs in navigation, from mechanical clocks to the critical role that Space-Borne Oscillators play in improving Performance of Satellite-Based Augmentation Systems and the strategic role of NIGCOMSAT-1R, the nascent African contribution to the Global Navigation Satellite System. View full abstract»

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  • Concise schemes for realizing 1-Wire® cyclic redundancy checks

    Page(s): 70 - 79
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (572 KB) |  | HTML iconHTML  

    The 1-Wire protocol provides a reliable means of detecting many types of errors that may occur in the bit stream it controls. It does so by carrying out cyclic redundancy check (CRC) calculations on data to be transmitted from 1-Wire and iButton slave devices, and appending the result to the data for onward transmission to the bus master as a block. Where the user of a 1-Wire or iButton device wishes to replicate the 1-Wire protocol in software, a number of application notes describe how to calculate 1-Wire CRC values. However, depending on the software implementation platform being used, these notes may not suffice for the average electronics systems engineer. This paper breaks down and compares a number of popular CRC calculation methods into basic tasks that may be interpreted for use in a programmable device that functions as a 1-Wire bus master; with a view to aid in further understanding of general CRC concepts. These tasks, which may also be extended to CRC calculations based on other generator polynomials, were verified by developing firmware routines that were run in a PIC 16F628A microcontroller functioning as the bus master to a single DS18S20 1-Wire Digital Thermometer. View full abstract»

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  • Filter — Trender — Interpretation: A design pattern for interpreting noisy and voluminous data

    Page(s): 80 - 84
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (302 KB) |  | HTML iconHTML  

    In this paper we propose and describe a new design pattern called FTI (Filter - Trender - Interpretation) for interpreting noisy and voluminous data sets. FTI consists of 3 consecutive processes: Filter which takes the original data and removes outliers and noise; given large volumes of data, Trender takes the filtered data and abstracts trends; and Interpretation uses rules from knowledge bases to perform qualitative reasoning on the trends to provide an analysis of the original data. In this paper we also show how FTI has been successfully applied to two different case studies. View full abstract»

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  • The analysis of Nigeria electricity market restructuring using game theory

    Page(s): 86 - 90
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (271 KB)  

    Investments in electricity markets contain high uncertainties about the future. It can also be seen as a game, as only a number of large players act in the market. A dynamic stochastic oligopolistic model to describe the production and investment in such a situation is developed and applied to the Nigerian electricity market. The demand growth rate is modeled as a stochastic variable with a time horizon of ten years. The strategies of firms consist of investment and production levels for base and peak load periods. The firms employ hydro, gas and steam capacities. Using the Sample-Path Adopted Open Loop Information Structure, the model contributes to the understanding of the dynamics of production, investment, and market power in medium time horizon. View full abstract»

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  • Energy yield of small wind turbines in low wind speed areas

    Page(s): 93 - 98
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (440 KB) |  | HTML iconHTML  

    The objective of this paper is to compare several commercially available small wind turbines systems, namely a vertical axis type with three helical blades without power limiting control above rated wind speed, multi-bladed furling controlled horizontal axis type, stall controlled horizontal axis type and blade pitch controlled horizontal axis type. The comparison is based on the annual energy yield per swept area (kWh/m2) and cost per generated electricity (€/kWh) in a low wind speed climate. Results show that most systems did not meet the performance stated by the manufacturers. Calculated annual energy yield of some turbines were higher than measured values from field test by up to a factor of two. Results also show that in large diameter turbines the €/kWh is lower than in small diameter turbines while many small diameter turbines had higher kWh/m2 than large diameter turbines. However, above 3m diameter, large diameter turbines performed better, having both low €/kWh and high kWh/m2. View full abstract»

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  • Multimachine transient stability analysis of the expanded 49 bus, 330KV Nigeria power system

    Page(s): 100 - 107
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (564 KB)  

    The recent power sector reform in Nigeria has thrown up enormous challenges in this sector, ranging from the construction of more power stations, new transmission lines and substations. The existing network of 8-plants and 26 bus-bars expanded to a network of 16 generating plants with 49 bus-bars. Power flow evaluation of this expanded 330KV network was done using the Newton-Raphson technique, while transient stability analysis of the power system was simulated by direct method using ode45 MATLAB programmed functions. The results show better network configuration, though buses interconnected via long transmissions lines recorded high voltage profile violation. The critical clearing times and stability margins for three-phase faults at buses 3 (line 3-44) and 31 (line 2-31) were established as 0.21 second, 0.238 and 0.29 second, 0.448 respectively. The result provided a suite of specifications and standards for the expanded grid system. View full abstract»

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  • Performance evaluation and efficiency improvement for Jebba, Kainji and Shiroro hydro power schemes

    Page(s): 115 - 118
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (251 KB) |  | HTML iconHTML  

    In this paper an attempt is made to evaluate performance indices based on industry - wide practice and to suggest possible approach for improving the operational efficiencies of Jebba, Kainji and Shiroro hydro power generating stations. To actualize that, data including average daily gross operating head, daily flow rate and daily energy generated were obtained from Jebba, Kainji and Shiroro power stations and the National Control Center (N.C.C) Osogbo. From the energy (MWh) generated the average daily power generated (MW) was computed. Consequently, the average operational efficiencies of Jebba, Kainji and Shiroro hydro schemes were evaluated and found to be 89.43%, 88.45% and 94.03% respectively. Similarly, performance indicators including deemed generation, auxiliary energy consumption, availability factor, capacity index, workforce deployment, forced outage factor, scheduled outage factor and average production cost were evaluated and technical inferences made. The study was limited to the year 2010 due to non - availability of data for other years. View full abstract»

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  • High Voltage Direct Current (HVDC) technology: An alternative means of power transmission

    Page(s): 121 - 125
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (375 KB) |  | HTML iconHTML  

    Energy consumption in the world is increasing, as well as the demand for efficient and quality electric power supply that ensures a greener environment. Consequently, the deployment of renewable energy sources has become imperative. The use of renewable resources like hydropower, solar and wind cannot be possible without electric transmission lines. High Voltage Alternating Current (HVAC), though an established technology of more than 100 years has its pros and cons. This paper presents an investigation into the use of HVDC technology as an alternative option for power transmission, the benefits, economic and reliability issues and most importantly, the environmental impact. In view of the crucial role played by a reliable Electric Power Transmission Grid in the economic development of nations, the integration of HVDC technology is recommended for developing countries, for neighboring countries who want to share spinning reserves and for developed countries who can tap the enormous solar and wind energies from remote deserts/offshore islands. View full abstract»

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  • Investigation of effects of heat sinks on thermal performance of microelectronic package

    Page(s): 127 - 132
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (329 KB) |  | HTML iconHTML  

    The concern about thermal performance of microelectronics is on the increase due to recent over-heating induced failures which have led to product recalls. Removal of excess heat from microelectronic systems with the use of heat sinks could improve thermal efficiency of the system. This paper investigates the effect of change in heat sink geometry on thermal performance of aluminium and copper heat sinks in microelectronics. Numerical studies on thermal conduction through an electronic package comprising a heat sink, chip, and thermal interface material were carried out. The thickness of the heat sink base and the height of the heat sink fins were varied in the study. The minimum and maximum temperatures of aluminium and copper heat sinks in the two models were investigated using steady state thermal conduction analysis. Better heat dissipation occurred in thinner base thickness and extended fins height for both aluminium and copper heat sinks. Aluminium heat sink recorded the lowest minimum temperatures in both investigations and is recommended as optimal thermal management material for heat sink production. View full abstract»

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  • A comparison of traditional teaching versus integrated Internet — Based learning in an American style university in Nigeria

    Page(s): 132 - 136
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (225 KB) |  | HTML iconHTML  

    In Nigeria, as more secondary schools and tertiary institutions contemplate developing educational materials and programs for delivery via the internet in order to complement traditional classroom teaching, there is the need to assess the effectiveness of the internet as a medium for delivering educational packages. This paper describes an exploratory study that investigated the possibility of integrating e-learning with traditional methods of teaching at an American styled university in Nigeria. By discussing possible reasons for the performance and disposition of sampled students towards e-learning, we suggest implications and effects of internet-based education on student learning. View full abstract»

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  • Effect of signal strength on handover in GSM networks in Owo, Ondo State, Nigeria

    Page(s): 138 - 143
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1010 KB) |  | HTML iconHTML  

    A major element in Global System for Mobile Communication (GSM) system is the splitting of the system into cells to enhance frequency reuse and efficient coverage. As the mobile station moves from the coverage area of one cell to another, the first connection is broken and a new one is made without any interruption in service, in a process called handover. If this critical process is performed incorrectly handover can result in loss of the call. All the Base Transceiver Stations (BTSs) of the four providers of GSM service in Owo were located on the physical map of Owo town in Ondo State, Nigeria and coverage of each network provider was investigated. GSM signal strength analyzer was used for measuring and monitoring the received signal strength and Bit Error Rate (BER) from each BTS at six geographical locations in the town for a period of time. The effect of signal strength on handover decisions between cells within the same Base Station Controller (BSC) of same networks in Owo was assessed for each provider. View full abstract»

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  • The saturation of the control channel in multi channel wireless access networks

    Page(s): 144 - 148
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (235 KB) |  | HTML iconHTML  

    The implementation of multi-channels in Ad hoc networks and Wirelesses Mesh Networks has been widely investigated. It envisaged that the approach would increase the capacity of wireless access networks. Results show that the implementation of multi channels does increase the capacity of access networks. However, the use of either a temporary signalling channel or a dedicated control channel has raised many research questions. The use of a control channel is viewed as a challenge to multi-channel schemes and is considered to be a limiting factor. It has been argued that the capacity of a single dedicated channel causes system bottlenecks as its capacity saturates. Unfortunately, this challenge has been given little attention hence it requires further investigation. This paper explores the saturation problem using the analytical and simulation models. Under the two approaches, the saturation problem is investigated in different scenarios in which the number of data transmitting channels is increased steadily. The investigations show that the capacity of the control channel degrades steadily as the number of channels is increased. Both the simulation and analytical results exhibit similar behaviour of the control channel. However, this paper does not investigate the response of the data channel to the increasing data traffic. View full abstract»

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  • Information capacity of adaptive MIMO OFDM wireless communication systems

    Page(s): 157 - 164
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (979 KB) |  | HTML iconHTML  

    In this paper, the mathematical analysis supported by computer simulation is used to find the information capacity of adaptive MIMO OFDM in digital communication systems. Result shows that in additive white Gaussian noise (AWGN) channel, the capacity performance of Least mean square (LMS) is poor while the recursive least square (RLS) shows an increase in capacity as the SNR increases. The joint channel parameters estimation in adaptive MIMO OFDM shows a 2dB SNR gain at BER of 10-5 when compared to individual parameter estimation. View full abstract»

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  • Development of an ANFIS-based QoS model for a GSM service provider (MTN Nigeria Kano region network)

    Page(s): 165 - 173
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (462 KB) |  | HTML iconHTML  

    MTN Nigeria is one of the leading GSM service providers in Nigeria with 40 million subscribers and as such Quality of Service (QoS) is of vital importance. Due to the mobility of subscribers and the complexity of radio waves in propagation, the radio part (GSM Capacity) is mostly the decisive factor affecting the Quality of Service of the GSM network. GSM Logical Control channels Data obtained from May 2006 to December 2009 from MTN, Kano region, were partitioned into training data set (142 data pairs represents 75% of the entire data) and checking data set (48 data pairs represents 25% of the entire data). Data obtained from January to March 2010 were used as validation data. The developed Adaptive Neuro Fuzzy Inference System (ANFIS) model was tested for Quality of Service on Logical Control Channel variables using Average Percentage Error (APE) and Performance comparison of data distribution. View full abstract»

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  • Direct Sequence CDMA system using Finite-Time Altered Sinusoidal Signals as orthogonal signatures

    Page(s): 174 - 177
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (238 KB) |  | HTML iconHTML  

    Direct Sequence CDMA (DS-CDMA) uses unique signature for each user to distinguish the information signals belonging to one user from another user. While orthogonal signatures that give values of zero for the cross correlation of different user signatures are highly desirable, only few of these kind of signatures are available. In this paper, the properties of Finite-Time Altered Sinusoidal Signals as orthogonal signatures for multiple access communication are presented. The effectiveness of this type of signature in combating multiple access interference was also evaluated and compared with the performance of the Legendre Polynomial and Walsh-Hadamard Signatures. The results obtained have been favourable. The Altered Sinusoidal Signature is a good candidate for application in DS-CDMA communication and wire line communication systems. View full abstract»

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  • Performance evaluation of constant bit rate and variable bit rate traffic models on Vehicular Ad hoc network using dynamic source routing protocol

    Page(s): 187 - 191
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1414 KB) |  | HTML iconHTML  

    In this paper, we describe a simulation performance of Vehicular Ad hoc network on different traffic models in a dynamic changing environment. The simulation results showed that as delay and jitter increases, the throughput of receiving bits decreases, the nodes stabilizes and the delay tends to drop at interval but packets do drop as the packet size increases. View full abstract»

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  • A non-iterative automated mechanism for image inpainting

    Page(s): 193 - 199
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1480 KB) |  | HTML iconHTML  

    Portions of an image may be damaged or missing. Inpainting is required to recover the missing portions. Inpainting is cleaning off dirt, filling discolored sports, and repairing torn, warped, or cracked in a damaged image. The existing Navier-Stokes Partial Differential Equations (PDE) method for inpainting is iterative by nature, with a time variable serving as iteration parameter. For reasons of stability a large number of iterations can be needed which results in a computational complexity that is often too large for interactive image manipulation. A non-iterative automated mechanism for image inpainting is proposed. Colors are treated as fluid that flow or diffuse from the surrounding areas into the empty region. Gains ranging from 9.44 dB to 19.49 dB were obtained with the non-iterative automated inpainting scheme. The automated inpainting scheme overcomes the computational complexity associated with the existing Navier-Stokes PDE inpainting method, and is more suitable for interactive image manipulations. View full abstract»

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  • Effects of inter-metallic compound on high temperature reliability of flip chip interconnects for fine pitch applications

    Page(s): 208 - 213
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (726 KB) |  | HTML iconHTML  

    Solder joint is a method widely used to attach electronic chip on substrate. It is a generally knowledge that solder joint contains inter-metallic compound (IMC) at interconnects of solder bump and copper pads. The magnitude of IMC layer thickness impacts reliability of chip level packages. Extensive experimental investigations are conducted, however complementary numerical studies are needed to fully characterise the effects of IMC on high temperature reliability of flip chip (FC) assembly. In this work, thermo-mechanical response of FC lead-free solder joints to accelerated temperature cycle (ATC) is investigated using finite element analysis (FEA) code. The ANAND's model is employed to study the inelastic, nonlinear, rate dependent and visco-plastic behaviour of two models of FC48D6.3C457DC mounted on printed circuit boards (PCBs). While one model consists of conventional joints without IMC, the other is realistic with IMC embedded. In the result analysis based on damage indicators such as induced strain, stress, plastic work and hysteresis, it is found that negative impact of IMC on static structural integrity of solder joint operating at high temperature ambient is nontrivial. View full abstract»

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  • Wet gas flow metering using PIV and tracer dilution

    Page(s): 222 - 224
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (292 KB) |  | HTML iconHTML  

    This paper introduces a prototype wet gas flow metering system, named “Uletech”, for flow measurement. The “Uletech” Wet Gas Meter (UWGM) is based on the combination of particle recognition and the use of Laser Imaging Technology in the form of Particle Imaging Velocimetry (PIV). PIV uses tracer particles which follow the gas or liquid phase. The high resolution digital laser cameras identify/recognize all the different sizes of particles (gas, oil and water) in a multiphase flow. The cameras have sufficiently high resolutions (pixel size) to "see" the tracer particles. The prevailing conditions of high pressure and temperature of the flow regimes makes actual measurement a great challenge. The velocity differences between phases (hold up and slip) means unless the velocities of individual phases and concentrations are known, the true flow rate is practically impossible to obtain. The system comprises two cameras, laser source, optical arrangement, computer data acquisition system, synchronizer and MATLAB based software. An algorithm that correlates the camera's view to the volume within the pipe has been developed through this research. The computer acquires image signals from the upstream and/or downstream cameras, and carries out the calculation of cross correlation between the two image frames so that the velocity of each pixel can be found. A Gas Liquid Chromatograph (GLC) provides the composition (concentration) of the gas and the liquid hydrocarbon (HC). The product of phase velocity and phase concentration provides the flow rate of the individual phase. This work provides theoretical analysis and experimental validations, and discusses the advantages of the system and its further development. View full abstract»

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  • Design, construction and testing of multipurpose energy saving LEDs and its implications on energy crisis in Nigeria

    Page(s): 226 - 230
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (261 KB) |  | HTML iconHTML  

    Solar energy and other alternative energy sources thrive on devices that consume lesser power than that used with conventional power sources, besides; the increasing cost of energy generation has left every one searching for low power consumption devices. Focusing on a very essential electrical device used in every home and offices, this paper presents “the design and construction of multipurpose energy saving light emitting diode (LED) light”. Bright white LED with broadband spectrum wavelength were connected in series and parallel form on a reflecting but not conducting surface. A dual Power supply design mode was used such that either direct ac source of 220V or a 12V DC supply is compatible with it. The LEDs are however not directly powered by the supply voltage as they were energized through a low frequency pulse-width modulated circuit. This ensures longer life span for the LED as they are not constantly on, though not noticeable to the eye. At the same time pulse-width modulation is ensured, which automatically effects varying light intensity. This singular feature makes this device multipurpose energy saving LED lamp, as it is sufficiently useful in the bedroom, sitting room, outside lighting or even street lightning. The durability of this device is ensured as it has been subjected to more than twelve month test. The physics and the electrical properties of the LED were considered in the course of the design, hence device analysis, calculation, experimental and test results as well as the implication of this design on energy crisis in Nigeria are included in the body of this paper. View full abstract»

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