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1
Azemi, Ghasem. "Mobile velocity estimation using a time-frequency approach." Thesis, Queensland University of Technology, 2003. https://eprints.qut.edu.au/15807/1/Ghasem_Azemi_Thesis.pdf.
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This thesis deals with the problem of estimating the velocity of a mobile station (MS)in a mobile communication system using the instantaneous frequency (IF) of the received signal at the MS antenna. This estimate is essential for satisfactory handover performance, effective dynamic channel assignment, and optimisation of adaptive multiple access wireless receivers. Conventional methods for estimating the MS velocity are based either on the statistics of the envelope or quadrature components of the received signal. In chapter 4 of the thesis, we show that their performance deteriorates in the presence of shadowing. Other velocity estimators have also been proposed which require prior estimation of the channel or the average received power. These are generally difficult to obtain due to the non-stationary nature of the received signal. An appropriate window which depends on the unknown MS velocity must first be applied in order to accurately estimate the required quantities. Using the statistics of the IF of the received signal at the MS antenna given in chapter 3, new velocity estimators are proposed in chapter 4 of this thesis. The proposed estimators are based on the moments, zero-crossing rate, and covariance of the received IF. Since the IF of the received signal is not affected by any amplitude distortion, the proposed IF-based estimators are robust to shadowing and propagation path-loss. The estimators for the MS velocity in a macro- and micro-cellular system are presented separately. A macro-cell system can be considered as a special case of a micro-cell in which there is no line-of-sight component at the receiver antenna. It follows that those estimators which are derived for micro-cells can be used in a macro-cell as well. In chapter 4, we analyse the performance of the proposed velocity estimators in the presence of additive noise, non-isotropic scattering, and shadowing. We also prove analytically that the proposed velocity estimators outperform the existing methods in the presence of shadowing and additive noise. The proposed IF-based estimators need prior estimation of both the IF of the received signal and Ricean K-factor. The IF estimation in a typical wireless environment, can be considered as a special case of a general problem of IF estimation in the presence of multiplicative and additive noise. In chapter 5, we show that current time-frequency approaches to this problem which are based on the peak of a time-frequency distribution (TFD) of the signal, fail because of the special shape of the power spectral density of the multiplicative noise in a wireless environment. To overcome this drawback, the use of the first-order moment of a TFD is studied in chapter 5. Theoretical analysis and simulations show that the IF estimator based on the first-order moment of a TFD exhibits negligible bias when the signal-to-additive noise ratio is more than 10 dB. The Ricean K-factor is not only necessary for velocity estimation in micro-cells, but also is a measure of the severity of fading and a good indicator of the channel quality. Two new methods for estimating the Ricean K-factor based on the first two moments of the envelope of the received signal, are proposed in chapter 6. Performance analysis presented in chapter 6, prove that the proposed K estimators are robust to non-isotropic scattering. Theoretical analysis and simulations which are presented in chapters 4 and 7 of this thesis, prove that the proposed velocity and K estimators outperform existing estimators in the presence of shadowing and additive noise.
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Azemi, Ghasem. "Mobile Velocity Estimation Using a Time-Frequency Approach." Queensland University of Technology, 2003. http://eprints.qut.edu.au/15807/.
Full textAbstract:
This thesis deals with the problem of estimating the velocity of a mobile station (MS)in a mobile communication system using the instantaneous frequency (IF) of the received signal at the MS antenna. This estimate is essential for satisfactory handover performance, effective dynamic channel assignment, and optimisation of adaptive multiple access wireless receivers. Conventional methods for estimating the MS velocity are based either on the statistics of the envelope or quadrature components of the received signal. In chapter 4 of the thesis, we show that their performance deteriorates in the presence of shadowing. Other velocity estimators have also been proposed which require prior estimation of the channel or the average received power. These are generally difficult to obtain due to the non-stationary nature of the received signal. An appropriate window which depends on the unknown MS velocity must first be applied in order to accurately estimate the required quantities. Using the statistics of the IF of the received signal at the MS antenna given in chapter 3, new velocity estimators are proposed in chapter 4 of this thesis. The proposed estimators are based on the moments, zero-crossing rate, and covariance of the received IF. Since the IF of the received signal is not affected by any amplitude distortion, the proposed IF-based estimators are robust to shadowing and propagation path-loss. The estimators for the MS velocity in a macro- and micro-cellular system are presented separately. A macro-cell system can be considered as a special case of a micro-cell in which there is no line-of-sight component at the receiver antenna. It follows that those estimators which are derived for micro-cells can be used in a macro-cell as well. In chapter 4, we analyse the performance of the proposed velocity estimators in the presence of additive noise, non-isotropic scattering, and shadowing. We also prove analytically that the proposed velocity estimators outperform the existing methods in the presence of shadowing and additive noise. The proposed IF-based estimators need prior estimation of both the IF of the received signal and Ricean K-factor. The IF estimation in a typical wireless environment, can be considered as a special case of a general problem of IF estimation in the presence of multiplicative and additive noise. In chapter 5, we show that current time-frequency approaches to this problem which are based on the peak of a time-frequency distribution (TFD) of the signal, fail because of the special shape of the power spectral density of the multiplicative noise in a wireless environment. To overcome this drawback, the use of the first-order moment of a TFD is studied in chapter 5. Theoretical analysis and simulations show that the IF estimator based on the first-order moment of a TFD exhibits negligible bias when the signal-to-additive noise ratio is more than 10 dB. The Ricean K-factor is not only necessary for velocity estimation in micro-cells, but also is a measure of the severity of fading and a good indicator of the channel quality. Two new methods for estimating the Ricean K-factor based on the first two moments of the envelope of the received signal, are proposed in chapter 6. Performance analysis presented in chapter 6, prove that the proposed K estimators are robust to non-isotropic scattering. Theoretical analysis and simulations which are presented in chapters 4 and 7 of this thesis, prove that the proposed velocity and K estimators outperform existing estimators in the presence of shadowing and additive noise.
3
Studener, Stephan [Verfasser]. "Embedded Control and Parameter Estimation Algorithms for Transport Process Systems : modeled by first-order Partial Differential Equations / Stephan Studener." Aachen : Shaker, 2011. http://d-nb.info/1069049832/34.
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Bashir, Zeeshan Ahmed. "MSB First Arithmetic Circuit for Motion Estimation." OpenSIUC, 2015. https://opensiuc.lib.siu.edu/theses/1723.
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AN ABSTRACT OF THE THESIS OF Zeeshan Ahmed Bashir, for the Masters of Science degree in Electrical and Computer Engineering, presented on 29th June 2015, at Southern Illinois University Carbondale TITLE: MSB FIRST ARITHMETIC CIRCUIT FOR MOTION ESTIMATION MAJOR PROFESSOR: Dr. Haibo Wang This thesis presents a novel design of arithmetic circuits that perform computation from MSB to LSB in a serial manner. In the MSB first serial computation, the result is gradually refined along the computation cycles. If the result is used to do a comparison with a threshold, such as in motion estimation applications, it is possible to draw the comparison conclusion in the middle of the computation and subsequently skip the rest of the computation. Thus the MSB-first serial computation potentially results in significant power reduction, making them attractive to low power applications. Unlike the existing MSB-first design that uses redundant number system, the proposed design is based on the widely used 2’ complementary number system, making the proposed circuits more compact and consuming less power as compared to the existing circuits that use signed digital bit numbers. The proposed arithmetic circuits have been used to implement variable block size motion estimation (VBSME) circuits, including block sizes of 4x4, 8x4, 8x8, 8x16 and 16x16 on a Xilinx Spartan 6 FPGA device. The performance of the proposed design is compared with the design based on existing MSB-first arithmetic circuit. The comparison shows the proposed design consumes significantly less power compared to the reference design.
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Wu, Chunzhang. "First passage time laws, derivation, estimation and application." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1996. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq30420.pdf.
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Fontenot, Rory. "Welfare Losses from First-Come-First-Serve Course Enrollment: Outcome Estimation and Non-Market Maximization." Scholarship @ Claremont, 2019. https://scholarship.claremont.edu/cmc_theses/2057.
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College course enrollment operates as a market under supply cap. Because of the limited number of seats available for any given course some students who have a higher demand for a course are unable to enroll. The current registration system at the Claremont Colleges functions as a random draw system with added time costs. The lack of price signalling in the markets leads to a loss in overall welfare of the student body. By running data through simulated demand curves I am able to determine, on average, how much welfare is being lost by a random draw system. The percent of maximum welfare achieved compared to maximum possible ranges from forty-nine to eighty percent and largely depends on the proportion of enrolled students to the sum of enrolled + enroll requests as well as the demand function type. With price signalling, the student body would be able to reach the maximum achievable welfare.
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Zhang, Fan. "Power system harmonic state estimation." Diss., Georgia Institute of Technology, 1994. http://hdl.handle.net/1853/13019.
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Aysal, Tuncer Can. "Filtering and estimation theory first-order, polynomial and decentralized signal processing /." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 327 p, 2007. http://proquest.umi.com/pqdweb?did=1257806501&sid=6&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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GUARNERA, FRANCESCO. "Advanced Methods for Image Forensics: First Quantization Estimation and Document Authentication." Doctoral thesis, Università degli studi di Catania, 2022. http://hdl.handle.net/20.500.11769/539559.
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Digital Forensics, and in a specific way Multimedia Forensics, has grown significantly
in the last years. Digital Forensics is defined as the branch of Forensic Science which
scientifically analyzes a digital evidence in order to obtain information about it. The
Digital 2021 Global Overview Report 1 published in January 2021 certifies that the
world’s population has reached the number of 7.83 billion. The 66.6% (i.e. 5.22
billion) use a mobile phone, the 59.5% (i.e. 4.66 billion) use internet and the 53.6%
(i.e. 4.2 billion) are social media users. The same report declares that from 2015 to
2020 the daily time spent with social media increased of 34 minutes (it was 1 hours
and 51 minutes in 2015) and that it’s destined to rise. In the described scenario
the number of shared images, video and audio (or Multimedia) contents become
difficult to manage. The described numbers and types of digital evidences have led
to the birth of several fields of Digital Forensics, faced from different communities:
Multimedia Security, Computer Forensics and Signal Processing. Image Forensics
has the goal to obtain information about the most popular digital evidence: images.
Developing new algorithms for forensic purposes was the main focus of my Ph.D..
In this thesis some advanced methods will be presented about two specific tasks:
the first one is related to the Camera Model Identification (CMI) with the goal to
identify the quantization table employed during the first JPEG compression; the
second one exploits the image as the digitization of a real paper sheet in order to
extract a unique fingerprint. Both the tasks produced relevant methods, widely
compared with state-of-the-art to demonstrate their scientific goodness.
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Majumdar, Ankur. "Security in power system state estimation." Thesis, Imperial College London, 2016. http://hdl.handle.net/10044/1/33744.
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With the power system evolving from passive to a more active system there is an incorporation of information and communication infrastructures in the system. The measurement data are more prone to tampering from attackers for mala fide intentions. Therefore, security and reliability of distribution have become major concerns. State estimation (SE), being the core function of the energy/distribution management system (EMS/DMS), has become necessary in order to operate the system efficiently and in a controlled manner. Although SE is a well-known task in transmission systems, it is usually not a common task in unbalanced distribution systems due to the difference in design and operation philosophy. This thesis addresses these issues and investigates the distribution system state estimation with unbalanced full three-phase modelling. The formulation, based on weighted least squares estimation, is extended to include the open/closed switches as equality constraints. This research then explores the vulnerabilities of the state estimation problem against attacks associated with leverage measurements. Detecting gross error particularly for leverage measurements have been found to be difficult due to low residuals. The thesis presents and discusses the suitability of externally studentized residuals compared to traditional residual techniques. Additionally, the masking/swamping phenomenon associated with multiple leverages makes the identification of gross error even more difficult. This thesis proposes a robust method of identifying the high leverages and then detecting gross error when the leverage measurements are compromised. All algorithms are validated in different IEEE test systems.
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Ghofranih, Jahangir. "Control and estimation of a chaotic system." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/29601.
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A class of deterministic nonlinear systems known as ”chaotic” behaves similar to noise-corrupted systems. As a specific example, Duffing equation, a nonlinear oscillator representing the roll dynamics of a vessel, was chosen for the study. State estimation and control of such systems in the presence of measurement noise is the prime goal of this research. A nonlinear estimation suitable for chaotic systems was evaluated against conventional methods based on linear equivalent model, and proved to be very efficient. A state feedback controller and a sliding mode controller were applied to the chaotic system and both techniques provided satisfactory results. Investigating the persistence of chaotic behavior of the controlled system is a secondary goal. Simulation results showed that the chaotic behavior persisted in case of the linear feedback controller, while in case of the sliding mode controller the system did not exhibit any chaotic behavior.Applied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate
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Elnaggar, Ashraf. "Variable regression estimation of unknown system delay." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/30804.
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This thesis describes a novel approach to model and estimate systems of unknown delay. The a-priori knowledge available about the systems is fully utilized so that the number of parameters to be estimated equals the number of unknowns in the systems. Existing methods represent the single unknown system delay by a large number of unknown parameters in the system model.
The purpose of this thesis is to develop new methods of modelling the systems so that the unknowns are directly estimated. The Variable Regression Estimation technique is developed to provide direct delay estimation. The delay estimation requires minimum excitation and is robust, bounded, and it converges to the true value for first-order and second-order systems. The delay estimation provides a good model approximation for high-order systems and the model is always stable and matches the frequency response of the system at any given frequency. The new delay estimation method is coupled with the Pole Placement, Dahlin and the Generalized Predictive Controller (GPC) design and adaptive versions of these controllers result. The new adaptive GPC has the same closed-loop performance for different values of system delay. This was not achievable in the original adaptive GPC. The adaptive controllers with direct delay estimation can regulate systems with dominant time delay with minimum parameters in the controller and the system model. The delay does not lose identifiability in closed-loop estimation. Experiments on the delay estimation show excellent agreement with the theoretical analysis of the proposed methods.Applied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate
13
Loh, A. P. "Uncertainty estimation and multivariable control system design." Thesis, University of Oxford, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.375267.
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Michiorri, Andrea. "Power system real-time thermal rating estimation." Thesis, Durham University, 2010. http://etheses.dur.ac.uk/469/.
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This Thesis describes the development and testing of a real-time rating estimation algorithm developed at Durham University within the framework of the partially Government-funded research and development project “Active network management based on component thermal properties”, involving Durham University, ScottishPower EnergyNetworks, AREVA-T&D, PB Power and Imass. The concept of real time ratings is based on the observation that power system component current carrying capacity is strongly influenced by variable environmental parameters such as air temperature or wind speed. On the contrary, the current operating practice consists of using static component ratings based on conservative assumptions. Therefore, the adoption of real-time ratings would allow latent network capacity to be unlocked with positive outcomes in a number of aspects of distribution network operation. This research is mainly focused on facilitating renewable energy connection to the distribution level, since thermal overloads are the main cause of constraints for connections at the medium and high voltage levels. Additionally its application is expected to facilitate network operation in case of thermal problems created by load growth, delaying and optimizing network reinforcements. The work aims at providing a solution to part of the problems inherent in the development of a real-time rating system, such as reducing measurements points, data uncertainty and communication failure. An extensive validation allowed a quantification of the performance of the algorithm developed, building the necessary confidence for a practical application of the system developed.
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Al-Othman, Abdul Rahman K. "Uncertainty modelling in power system state estimation." Thesis, Brunel University, 2004. http://bura.brunel.ac.uk/handle/2438/7889.
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As a special case of the static state estimation problem, the load-flow problem is studied in this thesis. It is demonstrated that the non-linear load-flow formulation may be solved by real-coded genetic algorithms. Due to its global optimisation ability, the proposed method can be useful for off-line studies where multiple solutions are suspected. This thesis presents two methods for estimating the uncertainty interval in power system state estimation due to uncertainty in the measurements. The proposed formulations are based on a parametric approach which takes in account the meter inaccuracies. A nonlinear and a linear formulation are proposed to estimate the tightest possible upper and lower bounds on the states. The uncertainty analysis, in power system state estimation, is also extended to other physical quantities such as the network parameters. The uncertainty is then assumed to be present in both measurements and network parameters. To find the tightest possible upper and lower bounds of any state variable, the problem is solved by a Sequential Quadratic Programming (SQP) technique. A new robust estimator based on the concept of uncertainty in the measurements is developed here. This estimator is known as Maximum Constraints Satisfaction (MCS). Robustness and performance of the proposed estimator is analysed via simulation of simple regression examples, D.C. and A.C. power system models.
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Babuscia, Alessandra. "Statistical risk estimation for communication system design." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/76087.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2012.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 281-295).
Spacecraft are complex systems that involve many subsystems and multiple relationships among them. The design of a spacecraft is an evolutionary process that starts from requirements and evolves over time. During this process, changes can affect mass and power at component, subsystem, and system level. Each spacecraft has to respect overall constraints in terms of mass and power. The current practice in system design deals with this problem by allocating margins to individual components and to individual subsystems. However, a statistical characterization of the fluctuations in mass and power of the overall system (i.e. the spacecraft) is missing. This lack can result in a risky spacecraft design that might not fit the mission constraints and requirements, or in a conservative design that might not fully utilize the available resources. This problem is especially challenging at the initial stage of the design, when high levels of uncertainty due to lack of knowledge are unavoidable. This research proposes a statistical approach to quantify the likelihood that the design of a spacecraft would meet the mission constraints in mass and power consumption, focusing on the initial stage of the design. Due to the complexity of the problem and the different expertise required to develop a complete risk model for a spacecraft design, the scope of this research is focused on risk estimation for a specific spacecraft subsystem: the communication subsystem. The current research aims to be a "proof of concept" of a risk-based design approach, which can then be further expanded to the design of other subsystems as well as to the whole spacecraft. The approach presented in this thesis includes a baseline communication system design tool, and a statistical characterization of the design risks through a combination of historical mission data and expert opinion. Different statistical techniques are explored to ensure that the amount of information extracted from data and expert opinion is maximized. Specifically, for statistics based on data, Kernel Density Estimator is selected as the preferred technique to extract probability densities from a database of previous space missions' components. Expert elicitation is generated through a four-part model which quantifies experts' sensitivity to biases, and uses this measurement to compose properly the assessments from different experts. Finally, an optimization framework is developed to compare multiple possible design architectures, and to select the one that minimizes design objectives, like mass and power consumption, while minimizing the risk associated with the same metrics. Examples of missions are applied to validate the model. Results show that the statistical approach recognizes whether the initial estimate of the system is an overestimation or an underestimation, providing a valuable tool to measure the risk of a communication system at the initial state of the design. Specifically, statistics based on historical data and on expert elicitation allow the designer to size contingency properly, providing a reliable estimation of mass and power in the initial stage of the design. Thanks to this method, the communication system designers will be able to evaluate and compare different communication architectures in a risk trade-off prospective across the evolution of the design. Extensions to different subsystems and to additional metrics (like cost) make this model applicable to a wider range of problems.
by Alessandra Babuscia.
Ph.D.
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Wang, Fei. "Pilot-Based Channel Estimation in OFDM System." University of Toledo / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1302129482.
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Ebrahimian, Mohammad Reza. "Power system operations : state estimation distributed processing /." Digital version accessible at:, 1999. http://wwwlib.umi.com/cr/utexas/main.
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Holmqvist, Niclas. "HANDHELD LIDAR ODOMETRY ESTIMATION AND MAPPING SYSTEM." Thesis, Mälardalens högskola, Inbyggda system, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-41137.
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Ego-motion sensors are commonly used for pose estimation in Simultaneous Localization And Mapping (SLAM) algorithms. Inertial Measurement Units (IMUs) are popular sensors but suffer from integration drift over longer time scales. To remedy the drift they are often used in combination with additional sensors, such as a LiDAR. Pose estimation is used when scans, produced by these additional sensors, are being matched. The matching of scans can be computationally heavy as one scan can contain millions of data points. Methods exist to simplify the problem of finding the relative pose between sensor data, such as the Normal Distribution Transform SLAM algorithm. The algorithm separates the point cloud data into a voxelgrid and represent each voxel as a normal distribution, effectively decreasing the amount of data points. Registration is based on a function which converges to a minimum. Sub-optimal conditions can cause the function to converge at a local minimum. To remedy this problem this thesis explores the benefits of combining IMU sensor data to estimate the pose to be used in the NDT SLAM algorithm.
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Pankaj, Rajesh Kumar. "A threshold strategy for a first in first out heteregeneous two server queueing system." Thesis, Massachusetts Institute of Technology, 1988. http://hdl.handle.net/1721.1/14756.
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Dolne, Jean J. "Estimation theoretical image restoration." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/47859.
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Thesis (S.M.)--Massachusetts Institute of Technology, System Design and Management Program, 2008.Includes bibliographical references.
In this thesis, we have developed an extensive study to evaluate image restoration from a single image, colored or monochromatic. Using a mixture of Gaussian and Poisson noise process, we derived an objective function to estimate the unknown object and point spread function (psf) parameters. We have found that, without constraint enforcement, this blind deconvolution algorithm tended to converge to the trivial solution: delta function as the estimated psf and the detected image as the estimated object. We were able to avoid this solution set by enforcing a priori knowledge about the characteristics of the solution, which included the constraints on object sharpness, energy conservation, impulse response point spread function solution, and object gradient statistics. Applying theses constraints resulted in significantly improved solutions, as evaluated visually and quantitatively using the distance of the estimated to the true function. We have found that the distance of the estimated psf was correlated better with visual observation than the distance metric using the estimated object. Further research needs to be done in this area. To better pose the problem, we expressed the point spread function as a series of Gaussian basis functions, instead of the pixel basis function formalism used above. This procedure has reduced the dimensionality of the parameter space and has resulted in improved results, as expected. We determined a set of weights that yielded optimum algorithm performance.
(cont.) Additional research needs to be done to include the weight set as optimization parameters. This will free the user from having to adjust the weights manually. Of course, if certain knowledge of a weight is available, then it may be better to start with that as an initial guess and optimize from there. With the knowledge that the gradient of the object obeys long-tailed distribution, we have incorporated a constraint using the first two moments, mean and variance, of the gradient of the object in the objective function. Additional research should be done to incorporate the entire distribution in the objective and gradient functions and evaluate the performance.
by Jean J. Dolne.
S.M.
22
Lipton-Duffin, Josh. "First results from a third generation KRIPES system." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2002. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/MQ63326.pdf.
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Wang, Yan. "First-principles study of the hydrogen-metal system." Diss., Georgia Institute of Technology, 1993. http://hdl.handle.net/1853/31067.
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Griffiths, Gareth Ivor Goulbourn. "First-principles studies of the ammonia-water system." Thesis, University of Cambridge, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.610671.
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Cameron, Alan, Tony Cirineo, and Karl Eggertsen. "The Family of Interoperable Range System Transceivers (First)." International Foundation for Telemetering, 1996. http://hdl.handle.net/10150/611408.
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International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, CaliforniaThe objective of the FIRST project is to define a modern DoD Standard Datalink capability. This defined capability or standard is to provide a solution to wide variety of test and training range digital data radio communications problems with a common set of components, flexible to fit a broad range of applications, yet be affordable in all of them. This capability is to be specially designed to meet the expanding range distances and data transmissions rates needed to test modern weapon systems. Presently, the primary focus of the project is more on software, protocols, design techniques and standards, than on hardware development. Existing capabilities, on going developments and emerging technologies are being investigated and will be utilized as appropriate. Modern processingintensive communications technology can perform many complex range data communications tasks effectively, but a large-scale development effort is usually necessary to exploit it to its full potential. Yet, range communications problems are generally of limited scope, so different from one another that a communication system applicable to all of them is not likely to solve any of them well. FIRST will resolve that dilemma by capitalizing on another feature of modern communications technology: its high degree of programmability. This can enable custom-tailoring of datalink operation to particular applications, just as a PC can be tailored to perform a multitude of diverse tasks, through appropriate selection of software and hardware components.
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Horbelt, Werner. "Maximum likelihood estimation in dynamical systems." [S.l. : s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=963810812.
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KAWAGUCHI, Nobuo, and Seigo ITO. "Bayesian Based Location Estimation System Using Wireless LAN." IEEE, 2005. http://hdl.handle.net/2237/15455.
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Fayegh, A. David. "Flood advisor : an expert system for flood estimation." Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/25069.
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Expert computer programs have recently emerged from research on artificial intelligence as a practical problem-solving tool. An expert system is a knowledge-based program that imitates the problem-solving behaviour of a human expert to solve complex real-world problems. While conventional programs organize knowledge on two levels: data and program, most expert programs organize knowledge on three levels: data, knowledge base, and control. Thus, what distinguishes such a system from conventional programs is that in most expert systems the problem solving model is treated as a separate entity rather than appearing only implicitly as part of the coding of the program.
The purpose of this thesis is twofold. First, it is intended to demonstrate how domain-specific problem-solving knowledge may be represented in computer memory by using the frame representation technique. Secondly, it is intended to simulate a typical flood estimation situation, from the point-of-view of an expert engineer. A frame network was developed to represent, in data structures, the declarative, procedural, and heuristic knowledge necessary for solving a typical flow estimation problem. The control strategy of this computer-based consultant (FLOOD ADVISOR) relies on the concept that reasoning is dominated by a recognition process which is used to compare new instances of a given phenomena to the stereotyped conceptual framework used in understanding that phenomena. The primary purpose of the FLOOD ADVISOR is to provide interactive advice about the flow estimation technique most suitable to one of five generalized real-world situations. These generalizations are based primarily on the type and quantity of the data and resources available to the engineer. They are used to demonstrate how problem solving knowledge may be used to interactively assist the engineer in making difficult decisions. The expertise represented in this prototype system is far from complete and the recommended solution procedures for each generalized case are in their infancy. However, modifications may be easily implemented as the domain-specific expert knowledge becomes available. It is concluded that over the long term, this type of approach for building problem-solving models of the real world are computationally cheaper and easier to develop and maintain than conventional computer programs.Applied Science, Faculty of
Civil Engineering, Department of
Graduate
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Vukovic, Divna, and Cecilia Wester. "Staff Prediction Analysis : Effort Estimation In System Test." Thesis, Blekinge Tekniska Högskola, Institutionen för programvaruteknik och datavetenskap, 2001. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-1739.
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This master thesis is made in 2001 at Blekinge Institute of Technology and Symbian, which is a software company in Ronneby, Sweden. The purpose of the thesis is to find a suitable prediction and estimation model for the test effort. To do this, we have studied the State of the Art in cost/effort estimation and fault prediction. The conclusion of this thesis is that it is hard to make a general proposal, which is applicable for all organisations. For Symbian we have proposed a model based on use and test cases to predict the test effort.
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Rababy, Nada. "Estimation of EMG conduction velocity using system identification." Thesis, McGill University, 1987. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=63819.
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Wang, Jing. "Marine power system protection using active impedance estimation." Thesis, University of Nottingham, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.537689.
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Chen, Jiaxiong. "Power System State Estimation Using Phasor Measurement Units." UKnowledge, 2013. http://uknowledge.uky.edu/ece_etds/35.
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State estimation is widely used as a tool to evaluate the real time power system prevailing conditions. State estimation algorithms could suffer divergence under stressed system conditions. This dissertation first investigates impacts of variations of load levels and topology errors on the convergence property of the commonly used weighted least square (WLS) state estimator. The influence of topology errors on the condition number of the gain matrix in the state estimator is also analyzed. The minimum singular value of gain matrix is proposed to measure the distance between the operating point and state estimation divergence.
To study the impact of the load increment on the convergence property of WLS state estimator, two types of load increment are utilized: one is the load increment of all load buses, and the other is a single load increment. In addition, phasor measurement unit (PMU) measurements are applied in state estimation to verify if they could solve the divergence problem and improve state estimation accuracy.
The dissertation investigates the impacts of variations of line power flow increment and topology errors on convergence property of the WLS state estimator. A simple 3-bus system and the IEEE 118-bus system are used as the test cases to verify the common rule. Furthermore, the simulation results show that adding PMU measurements could generally improve the robustness of state estimation.
Two new approaches for improving the robustness of the state estimation with PMU measurements are proposed. One is the equality-constrained state estimation with PMU measurements, and the other is Hachtel's matrix state estimation with PMU measurements approach. The dissertation also proposed a new heuristic approach for optimal placement of phasor measurement units (PMUs) in power system for improving state estimation accuracy. In the problem of adding PMU measurements into the estimator, two methods are investigated. Method I is to mix PMU measurements with conventional measurements in the estimator, and method II is to add PMU measurements through a post-processing step. These two methods can achieve very similar state estimation results, but method II is a more time-efficient approach which does not modify the existing state estimation software.
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Harry, Cyril Massey. "A thermodynamics-system approach to software resource estimation." Thesis, Imperial College London, 1991. http://hdl.handle.net/10044/1/46807.
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Alves, Tânia Sofia Vilaranda. "Stereo vision system for 3D ball trajectory estimation." Master's thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/17934.
Full textAbstract:
Mestrado em Engenharia de Computadores e TelemáticaO sistema de visão humano e um sistema complexo e extraordinário. O ser humano usa o que se denomina por esteropsia para obter uma noção da profundidade dos objectos que o rodeiam. Os dois olhos capturam duas imagens do mundo e o cérebro processa e interpreta a informação capturada. Um sistema de visão estéreo e baseado nesta capacidade. O sistema integra duas ou mais camaras que capturam visões diferentes do mundo. As imagens são processadas para obter informação 3D sobre os objectos e do próprio mundo. Estéreo é uma área importante da visão por computador que e usada em várias aplicações como por exemplo detecção de pessoas, navegação em robôs móveis, automação industrial, veículos de condução autónoma entre outros. Hoje em dia, a visão por computador começa também a ser usada em desporto, nomeadamente futebol, ténis e hockey. O objectivo desta tese é apresentar um sistema de visão estéreo que consiga detectar objectos coloridos em tempo real e estimar a sua trajectória em 3 dimensões. Este documento apresenta os passos necessários para obter um sistema funcional incluindo a calibração das camaras, sincronização de camaras, detecção de objectos e a relação da sua posição nas diferentes camaras. Também apresenta experiências e resultados que confirmam a eficácia do sistema.
The human vision system is a very complex and amazing system. Humans use what is called stereopsis to perceive depth and 3D objects. The two eyes capture two di erent images of the surrounding world and it is the brain that processes and interprets the information captured. A stereo vision system is based on this ability. The system integrates two or more cameras that capture di erent views of the world. The images are processed to obtain information about 3D objects and the world itself. Stereo is an important area of computer vision used in several applications such as people tracking, mobile robotics navigation, industrial automation, automonomous vehicle research and others. Nowadays computer vision is starting to be used in sports as well, namely soccer, tennis and hockey. The main goal of this thesis is to present a stereo vision system that is able to detect colored objects in real time and estimate their trajectory in 3 dimensions. This document presents the necessary steps to have a fully functioning stereo system including camera calibration, camera synchronization, object detection and the relation of the its position in the di erent cameras. It also presents system experiments and results that con rm the e ectiveness of the system.
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Kan, Ka Ho. "Location estimation system based on the GSM network." HKBU Institutional Repository, 2004. http://repository.hkbu.edu.hk/etd_ra/524.
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Liu, Kuang-Yu, and 劉光宇. "Viewing Angle Detection and Estimation Systems for Driving Assistance using First-Person-Vision." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/68613450289313540588.
Full textAbstract:
碩士國立清華大學
電機工程學系
102
This thesis proposes an intelligent vehicle system to identify the driver improper driving behavior using the so-called “first-person vision” (FPV) technology. Different from conventional computer vision, FPV is based on the person wearing a goggles camera representing the subject vision. There are two technologies proposed in this thesis: vehicle exterior/interior view detection and driver viewing angle estimation. For the first method, we use “bag of words” image classification approach by applying FAST+BRIEF feature descriptor in the dataset collected in advance. Then, we establish the first-person vision “vocabulary dictionary”, encoding an input image into a feature vector. Finally, we apply SVM classifier to detect whether the input image is from the inside of a vehicle, and further identifying the driver current attention. For the second method, we install an extra vehicle-mounted camera to record the image in front of the vehicle and to deem it as world coordinate reference for viewing angle estimation. Then, we find the relationship between the world and first-person-vision camera coordinate. Finally, we may further estimate the viewing direction of driver.
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Chethan, Kumar M. "First Principles Based Mobility Estimation of Graphene." Thesis, 2018. https://etd.iisc.ac.in/handle/2005/4915.
Full textAbstract:
Electron-phonon coupling (EPC) plays a vital role in detecting transport properties
(e.g. mobility) of any material. First principles-based estimation of the
mobility for any new material could act as a useful guideline for experimentalist.
Inclusion of EPC in quantum transport models that involves non-equilibrium
Greens function (NEGF) formalism with density functional theory (DFT), is numerically
demanding. Because of this computational burden, some approximations
are made such as phonon can be described within harmonic approximation
which neglects non-harmonic part. However, at room temperature there will be
non-harmonic contribution.
In a new technique, molecular dynamics (MD) is combined with Landauer transport
equation, for the estimation of mobility. Molecular dynamics simulation
inherently includes non-harmonic e ect. Temperature dependent mobility is calculated
by combining classical MD simulation with DFT calculation. The main
purpose of the MD is to generate the snapshot of the thermally disordered solid.
From each of these Snapshots, transmission spectrum is calculated. These transmissions
are averaged over a number of samples and conductance is calculated
using Landauer approach to yield good results. The charge concentration for this
mobility is calculated using Fermi-Dirac statistics. Using calculated resistivity
obtained from di erent temperature and the carrier concentration, temperature
dependent mobility is estimated.
However, such technique has so far been demonstrated for bulk and one-dimensional
materials. In this work we investigate if the same technique is applicable for two
dimensional materials. We apply the same technique to estimate the temperature
dependent mobility of graphene. Our results are in good agreement with the mobility
estimated using other first principles-based techniques (DFT+Boltzmann
Transport Equation).
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Dooley, Ellen V. "Age estimation from features of the first rib." Thesis, 2020. https://hdl.handle.net/2144/41215.
Full textAbstract:
Several techniques for estimating adult age-at-death are used in biological and forensic anthropology, including morphological changes of the ribs. However, due to human variation and taphonomic damage, it remains difficult to produce accurate and meaningful age-at-death estimations based on skeletal remains. This research further explores morphological changes to the first rib, which is easily identifiable and relatively robust, including the costal face and tubercle facet identified by Kunos’ (1999) and modified by DiGangi et al. (2009). A total of 400 European American individuals (f=200; m=200) from the William M. Bass Donated Skeletal Collection at the University of Tennessee, Knoxville, were observed using modified descriptions for Kunos’ (1999) five traits of the costal face and tubercle facet, on an ordinal scale of 1-8. Additionally, bone quality was assessed on an ordinal scale of 1-3 and was incorporated as a variable in order to improve estimations. Exploratory statistical analysis demonstrates that all eleven traits correlate with age at a statistically significant level, with bone quality being the most significant feature for both sexes. Female and male differences were found, and cross-validated ordinal logistic regression equations are presented for each. The resulting AIC table estimates 100% of the male and female sample correctly, though the produced ranges are too large to be forensically relevant. The results of this research underscore the importance of developing age estimation methods on skeletal regions that are under researched and for those that are more resistant to taphonomic damage.
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Lin, Feng-Chu, and 林芳楚. "Various Slope Estimation System." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/79966546300060077597.
Full textAbstract:
碩士國立交通大學
電控工程研究所
100
We still need to pedal when riding an e-bike, but the differ¬ence is that there is a DC motor in the front wheel. During pedaling, the rider gets addi¬tional power from the motor, and that will enhance the comfort of pedaling. Gener¬ally speaking, categories of various resistant torques are nothing else but slope, wind resistance, and road friction. However, the power of motor and the timing of shifting gear have to adjust to different resistances. This thesis presents a system which estimates vari¬ous slope based on an e-bike and it will be useful for e-bike manufacturers. During riding, the MCU will do a real-time discrimination by computing data which includes the DC bus current of Current-protection and the voltage signal for controlling motor. Some programs will be designed according to the relationship between the resistance, the current, and the torque of DC motor. The above is described in chapter 2 and chapter 3. Finally, we will check whether the system is feasible, so we choose "slope" which is the factor of experiment. This factor is more stable and can be found easier than oth¬ers. There are two experiments, one is the accuracy of discrimination and the other is about response time. However, we will say that this system is better than the slope sensor on the e-bike in chapter 4.
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Song, Hosin. "Nonparametric identification and semi-nonparametric estimation of first-price auctions." 2007. http://etda.libraries.psu.edu/theses/approved/WorldWideIndex/ETD-2062/index.html.
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Su, Ching-Long, and 蘇慶龍. "An MSD-First Architecture and Its Application to Motion Estimation." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/34464105980922149884.
Full textAbstract:
博士國立交通大學
電子工程系
91
This dissertation explores the issues of the MSD-first processing and derives a novel MSD-first architecture strategy for VLSI implementations. The architecture is very suitable for the multimedia and communication systems. We demonstrate this design methodologies by an ME example. The implementation results show that our MSD-first strategy totally supports 5.04 times SAD (summation of absolute difference) operations per unit area of the conventional digit-parallel ones. The MSD-first processing adopts the on-line arithmetic components that are widely used for speed-up computations in the past. However, the redundant number system of the on-line arithmetic makes its implementation cost, which doubles that of the digit-parallel approaches. Because the redundant number system absorbs the possible carry (or borrow) of the arithmetic operations, the carry propagation chain will be broken between adjacent digit operations. Beginning in the 1960’s, the major researches of the MSD-first processing still focus on the high-performance arithmetic component design. This dissertation proposes a novel MSD-first architecture design approach for reducing arithmetic operations. For the ME example, our system decomposes the SAD and comparison operations of all the candidates into digit level with MSD-plane first. These comparisons are interleaved into SAD’s to distinguish MV till the appearance of the best matching. The related operations of the candidates with large SAD enough not to be MV can be also removed during the processing. The system is suitable for the multimedia applications since the human perception of the visual and audio quality is not fully sensitive. There are numbers of algorithms with inaccurate computation requirements in a multimedia system such as quantization and the search of MV. Moreover, the time-variable characteristics of the communication channel are also suitable for the MSD-first implementations. To sum up, the novel architecture design methodology detects and removes those digit-level redundant computations of the algorithms embedded as well as preserving the high throughput of on-line arithmetic components. For implementations, the novel MSD-first architecture faces a series of design issues, which contain decomposing the original algorithm into the digit-level operations, reorganizing them to remove the possible redundant operations, the on-line arithmetic component optimization and deriving the digit-level parallelism to boost the system performance. Their considerations are all different from the traditional digit-parallel input ones. The dissertation proposes the total solutions for the ME example. In the system level, we analysis the ME algorithm and derive the MSD-first ME with its architecture. An essential C-language program simulates the system efficiency. The detail result versus the video characteristics is also discussed. Besides, the memory subsystem design for the external memory provides a solution to reduce the memory I/O bandwidth. In the circuit level, the key component of the on-line arithmetic comparator manipulates the removes of the digit-level SAD operations. This performance dominates the system efficiency. Moreover, the on-line arithmetic SAD is optimized for low circuit complexity. A performance-driven design of the systolic array processor and the complete MSD-first architecture for the MPEG video compression are shown in the dissertation. This design explores the digit-level parallelism of the MSD-first ME, which achieves one time access for the MV searching of a MB. We will compare the results, which include the gate count and the performance, with a traditional digit-parallel inputs design. Finally, a detail analysis of our design methodology is given. The result shows our proposed MSD-first strategy yields 5.04 times hardware efficiency (MV/gate_count in ‘SUZIE’). The MSD-first ME removes 47.4% digit-SAD operations and the on-line arithmetic implementation contributes the other 2.67 times gains.
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Afariebor, Roland. "Identification and estimation of a first order bilinear time series /." 2001.
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Jui-Chi, Chen, and 陳瑞琦. "Channel Estimation for OFDM System." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/fmxzg4.
Full textAbstract:
碩士南台科技大學
電子工程系
95
The OFDM system was proposed for its efficiency in eliminanting the effects of multipath fading and impulse noise, However, in wideband mobile channel, the channel characteristic is usually frequency selective and time-varying. It is crucial to estimate the channel response for the receiver end to enhance the system performance. In this paper, we propose a channel estimation for the OFDM based on the check sum of the transmitted data. From the simulation results, it demonstrates that the our proposed method has superior performance in the fast fading channel.
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Bengani, Saurav Kumar. "Estimation of power system frequency." Thesis, 2013. http://ethesis.nitrkl.ac.in/4930/1/109EE0261.pdf.
Full textAbstract:
Frequency is an important parameter in power system for indicating the dynamic balance between amount of power generated and amount of power consumed. Small changes in system frequency can affect the operation of a power system in a great manner. Thus, estimating the frequency is one of the most important task in the power system operation. A least mean square (LMS) algorithm with varying step size to estimate the frequency is studied in this report and its performance under the influence of harmonics, noise, unbalanced conditions, step changes in frequency, etc is observed through various simulations. Next, Frequency estimation is carried out with an improved Non-linear Least Squares (NLS) method in which frequency is estimated through a 1-D search over a specified range. The validity of method under different conditions including line to ground fault is also tested. This method is also verified using the data obtained from an experimental setup consisting of a non-linear load.
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(10717698), Runhua Sun. "Bike Share System - Rebalancing Estimation and System Optimization." Thesis, 2021.
Find full textAbstract:
Bike share system (BSS)
has received increasing attention in research for its potential economic and environmental
benefits. However, some research has pointed out the negative sustainability
impacts of BSS from rebalancing activity, due to its greenhouse gas (GHG)
emissions and additional vehicle travels. Additionally, bike and station
manufacturing also bring considerable emissions to the system. Therefore, it is
important to analyze the current rebalancing efficiency and sustainability of
BSSs, and to assist the BSS operators in optimizing the BSS design. Existing
studies lack tools to estimate the real-world rebalancing activities and
vehicle usage for system sustainability evaluation and improvements. To address
this gap, this research first proposed a framework to estimate rebalancing
activities and applied a clustering-based method to estimate the rebalancing
vehicle use. Applying the framework to the BSSs in Chicago, Boston, and Los Angeles,
this study estimated the rebalancing operation and compared the rebalancing
efficiencies among the three systems. The analysis results show that 1) only a
small proportion of stations and bikes were involved in the daily rebalancing
activities; 2) most rebalancing
activities were operated during the daytime, while the overnight rebalancing
was limited; 3) the system scale, trip demand, and station types are
critical for the rebalancing efficiency; and 4) reducing the rebalancing
activities at self-rebalance stations could help to improve the rebalancing
efficiency and benefits system sustainability. Additionally, the sustainability performance
(e.g., carbon emissions) of BSS is not only decided by the rebalance, but also
the manufacturing of bikes and stations. It is important to consider all these factors
when optimizing a BSS. The existing literature on system improvement for the BSSs
lacks an integrated view, and a well-designed
integrated model for current BSS improvement is needed. The second part of this
thesis built a simulation-based optimization model and generated 2400 scenarios
for evaluation. This model aims to minimize the expansion investment,
rebalancing mileage, and maximize the system demand and service rate. A Weight
Sum Model is applied to solve the multi-criteria
decision analysis. The model results show that the best system improvement is
to build a new station with a small capacity and initial bikes. The investment
and location impacts are discussed to find the tradeoff among expansion strategies.
A sensitivity analysis is conducted to evaluate how different weight
combinations (refer to different preferences in decision making) impact the
preferred station configuration (docks and bikes) and new station locations.
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Hsu, Hsin-Yi, and 許欣怡. "Estimation of credit default risk of corporate --- first passage time approach." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/78369440227264326964.
Full textAbstract:
碩士開南管理學院
財務金融系碩士班
93
The importance of Credit Risk Management is rising because of the diversification of financing channels in corporations. How to predict the possibility of financial distress and probability of default happened exactly in corporations is a very critical issue in the Credit Risk Management. There are three methods having been adopted: the credit scoring model, the creditmetrics and the option pricing model. In this paper, we extend models of Leland’s 94 of a closed-form solution between corporation equity market value and assets market value and Duan’s 94 of maximum likelihood estimation method to calculate the probability of default prediction in corporations. Finally, this study pointed out these models and methods we used are highly accurate in calculating the probability of default prediction. These models are efficient in financial distress predicting.
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Huang, Yi-Shan, and 黃義珊. "Channel Estimation for Uplink WCDMA System." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/41067972043122808842.
Full textAbstract:
碩士國立交通大學
電子工程系
88
In this thesis, the channel estimation methods for next generation wideband code-division multiple-access (WCDMA) system were studied. Coherent WCDMA reverse link periodically transmitting pilot symbols in front of every control channel slot to estimate the fading channel is considered. For the WCDMA reverse link, fast transmit power control (TPC) and power saving of mobile station are the important issues. We proposed moving average method and sliding window methods to overcome the decision delay of the control symbols. We also proposed a low-complexity channel estimation method based on both control and data channels to reduce the required power of a control channel. After investigation and simulation in this thesis, we conclude that the sliding window type-VI channel estimation based on both control and data channels is better than other methods in the overall performance of BER, delay time and power reduction.
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ZHAO, FENG-BIN, and 趙峰彬. "An expert software cost estimation system." Thesis, 1991. http://ndltd.ncl.edu.tw/handle/79059320838155606287.
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Yeh, Jih-Hsiang, and 葉日翔. "Dose estimation of digital mammography system." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/84290382092447153282.
Full textAbstract:
碩士國立陽明大學
生物醫學影像暨放射科學系暨研究所
96
The purpose of this study was to estimate the radiation dose of the digital mammography system. The radiation dose and image quality of different exposure setting were estimated with the standard American College of Radiology (ACR) phantom. The results showed that the most suitable exposure setting was 30 kVp and 47.7 mAs. The mean glandular dose at 30 kVp and 47.7 mAs was 1.40 mGy, and the effective dose was 0.07 mSv. The effective dose of 0.07 mSv was about 1/34 of the natural background radiation exposure per year. In this study, a comparison in mean glandular dose of digital mammography system to that of traditional mammography system was conducted. The results showed that the digital mammography system can provide better image quality with lower mean glandular dose. Measurement of mean glandular dose in this study was proceed with ionization chamber, thermoluminescent dosimeters (TLDs), and radiophotoluminescent glass dosimeters (RPLGDs). Because of the high density of RPLGDs, the measurement of mean glandular dose with RPLGDs placed on the surface of the phantom was not adaptable. The experimental results indicated that the mean glandular dose measured by TLDs and RPLGDs was comparable to ionization chamber, expect for the tube voltage of 24 kVp. The difference between TLDs and ionization chamber was within 6%, and the difference between RPLGDs and ionization chamber was within 5%.
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Jan, Yao-Yang, and 詹曜陽. "Economic Estimation of Classroom Lighting System." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/48505782467673433170.
Full textAbstract:
碩士崑山科技大學
電子工程研究所
100
The main issue of this thesis is a comparison of traditional T9 fluorescent, T5 fluorescent lamps, and Light Emitting Diode (LED) in campus classroom. First, the author measures illumination of classroom using a digital instrument. Then, a lighting simulation software is implemented analysis for T9, T5, and LED lights. This software can output different analysis results such as: (1) power consumption, (2)illuminance distribution ( i.e., maximum, minimum, and average illuminances),(3) electricity tariffs in accordance with Taipower company. The research results can show up the effective of LED in campus lighting.