Relevant bibliographies by topics / Global Positioning System – Mathematical models

Academic literature on the topic 'Global Positioning System – Mathematical models'

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Published: 10 December 2022
Last updated: 28 January 2023

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Journal articles on the topic "Global Positioning System – Mathematical models"

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Liu, Peng, Honglei Qin, and Li Cong. "The Unified Form of Code Biases and Positioning Performance Analysis in Global Positioning System (GPS)/BeiDou Navigation Satellite System (BDS) Precise Point Positioning Using Real Triple-Frequency Data." Sensors 19, no. 11 (May 30, 2019): 2469. http://dx.doi.org/10.3390/s19112469.

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Multi- system and multi-frequency are two key factors that determine the performance of precise point positioning. Both multi-frequency and multi-system lead to new biases, which are not solved systematically. This paper concentrates on mathematical models of biases, influences of these biases, and positioning performance analysis of different observation models. The biases comprise the inter-frequency clock bias in multi-frequency and the inter-system clock bias in multi-system. The former is the residual differential code biases (DCBs) from receiver clock and satellite clock and usually occurs at the third frequency, the latter is the deviation of the receiver clock errors in different systems. Unified mathematical models of the biases are presented by analyzing the general formula of observation equations. The influences of these biases are validated by experiments with corresponding observation models. Subsequently, the experiments, which are based on the data at five globally distributed stations in Multi-Global Navigation Satellite System (GNSS) Experiment (MGEX) on day of year 100, 2018, assess positioning performance of different observation models with combination of frequencies (dual-frequency or triple- frequency) and systems (BeiDou Navigation Satellite System (BDS) or Global Positioning System (GPS)). The results show that the performances of triple-frequency models are almost as the same level as the dual-frequency models. They provide scientific support for the triple-frequency ambiguity-fixed solution which has a better convergence characteristic than dual-frequency ambiguity-fixed solution. Furthermore, the biases are expressed as an unified form that gives an important and valuable reference for future research on multi-frequency and multi-system precise point positioning.
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Tanaka, Toshiki, Takuji Ebinuma, Shinichi Nakasuka, and Heidar Malki. "A Comparative Analysis of Multi-Epoch Double-Differenced Pseudorange Observation and Other Dual-Satellite Lunar Global Navigation Systems." Aerospace 8, no. 7 (July 15, 2021): 191. http://dx.doi.org/10.3390/aerospace8070191.

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In this study, dual-satellite lunar global navigation systems that consist of a constellation of two navigation satellites providing geo-spatial positioning on the lunar surface were compared. In our previous work, we proposed a new dual-satellite relative-positioning navigation method called multi-epoch double-differenced pseudorange observation (MDPO). While the mathematical model of the MDPO and its behavior under specific conditions were studied, we did not compare its performance with other dual-satellite relative-positioning navigation systems. In this paper, we performed a comparative analysis between the MDPO and other two dual-satellite navigation methods. Based on the difference in their mathematical models, as well as numerical simulation results, we developed useful insights on the system design of dual-satellite lunar global navigation systems.
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Pitchumani, S. Naveen, S. Arun Sundar, T. Srinivasan, and S. Savithri. "Mathematical Modelling of Indian Regional Navigation Satellite System Receiver." Defence Science Journal 67, no. 4 (June 30, 2017): 443. http://dx.doi.org/10.14429/dsj.67.11547.

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<p class="p1">At present the armoured fighting vehicles are equipped with either global positioning system (GPS) receivers or integrated inertial navigation system (INS)/GPS navigation systems. During hostile situations, the denial/degradation of the GPS satellite signals may happen. This results in the requirement of an indigenous satellite based navigation system. Indian Space Research Organisation has developed an indigenous Indian regional navigation satellite system (IRNSS), with a seven satellite constellation to provide independent position, navigation and timing services over India and its neighbouring regions. In this paper, the development of IRNSS receiver using MATLAB as per IRNSS signal in space interface control document for standard positioning service is discussed. A method for faster IRNSS signal acquisition in frequency domain and delay locked loop code tracking for the acquired satellite signals are used. Models for navigation message decoding and pseudo range/user position calculations are developed using the algorithms provided in IRNSS ICD.</p>
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Nawaz, Asif, Huang Zhiqiu, Wang Senzhang, Yasir Hussain, Amara Naseer, Muhammad Izhar, and Zaheer Khan. "Mode Inference using enhanced Segmentation and Pre-processing on raw Global Positioning System data." Measurement and Control 53, no. 7-8 (May 27, 2020): 1144–58. http://dx.doi.org/10.1177/0020294020918324.

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Many applications use the Global Positioning System data that provide rich context information for multiple purposes. Easier availability and access of Global Positioning System data can facilitate various mobile applications, and one of such applications is to infer the mobility of a user. Most existing works for inferring users’ transportation modes need the combination of Global Positioning System data and other types of data such as accelerometer and Global System for Mobile Communications. However, the dependency of the applications to use data sources other than the Global Positioning System makes the use of application difficult if peer data source is not available. In this paper, we introduce a new generic framework for the inference of transportation mode by only using the Global Positioning System data. Our contribution is threefold. First, we propose a new method for Global Positioning System trajectory data preprocessing using grid probability distribution function. Second, we introduce an algorithm for the change point–based trajectory segmentation, to more effectively identify the single-mode segments from Global Positioning System trajectories. Third, we introduce new statistical-based topographic features that are more discriminative for transportation mode detection. Through extensive evaluation on the large trajectory data GeoLife, our approach shows significant performance improvement in terms of accuracy over state-of-the-art baseline models.
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Ordóñez, Celestino, Marta Sestelo, Javier Roca-Pardiñas, and Enrique Covián. "Variable selection in regression models used to analyse Global Positioning System accuracy in forest environments." Applied Mathematics and Computation 219, no. 4 (November 2012): 2220–30. http://dx.doi.org/10.1016/j.amc.2012.08.069.

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Lucjan Setlak and Rafał Kowalik. "RTK Kinematic Positioning Accuracy with Double Phase Difference of SIS GNSS Signals." Communications - Scientific letters of the University of Zilina 23, no. 3 (July 1, 2021): E35—E45. http://dx.doi.org/10.26552/com.c.2021.3.e35-e45.

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The article presents results of verification of the kinematic measurements usefulness for precise real-time positioning RTK in the local reference system. These measurements allow for continuous RTK measurements in the event of temporary interruptions in radio or internet connections, which are the main reason for interruptions in RTK kinematic measurements and cause a decrease in the reliability and efficiency of this positioning method. Short interruptions communication are allowed during the loss of the key correction stream from the local RTK support network, so the global corrections obtained from the geostationary satellite are used. The aim of the article was to analyze the accuracy of measuring the position of moving objects. Practical conclusions were formulated according to the research subject, the presented mathematical models, the experiment and the analysis of the obtained results.
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Tiano, A., A. Zirilli, M. Cuneo, and S. Pagnan. "Multisensor Data Fusion Applied to Marine Integrated Navigation Systems." Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment 219, no. 3 (September 1, 2005): 121–30. http://dx.doi.org/10.1243/147509005x10512.

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This paper deals with the problem of designing a flexible and accurate integrated navigation system (INS) for marine craft. The proposed INS is based on the integration of a global positioning system (GPS) with a compass and a speed log. After introducing the scopes and functions of the proposed INS, mathematical models of its main components are presented. Then the development of a new multisensor data fusion algorithm for carrying out an accurate estimation of the main state variables is presented. The theoretical background for the sensor fusion is based on the classical Kalman filter theory, which allows to update an a priori position estimate, given by a dead-reckoning system, with the information supplied by a GPS positioning system. Finally the filtering algorithm is extended in the framework of interval analysis and fuzzy set theory in order to improve the reliability and robustness of the estimation algorithm. The validity of the proposed approach is demonstrated by simulation examples applied to a container ship navigating in realistic conditions.
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Prochniewicz, Dominik, Kinga Wezka, and Joanna Kozuchowska. "Empirical Stochastic Model of Multi-GNSS Measurements." Sensors 21, no. 13 (July 3, 2021): 4566. http://dx.doi.org/10.3390/s21134566.

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The stochastic model, together with the functional model, form the mathematical model of observation that enables the estimation of the unknown parameters. In Global Navigation Satellite Systems (GNSS), the stochastic model is an especially important element as it affects not only the accuracy of the positioning model solution, but also the reliability of the carrier-phase ambiguity resolution (AR). In this paper, we study in detail the stochastic modeling problem for Multi-GNSS positioning models, for which the standard approach used so far was to adopt stochastic parameters from the Global Positioning System (GPS). The aim of this work is to develop an individual, empirical stochastic model for each signal and each satellite block for GPS, GLONASS, Galileo and BeiDou systems. The realistic stochastic model is created in the form of a fully populated variance-covariance (VC) matrix that takes into account, in addition to the Carrier-to-Noise density Ratio (C/N0)-dependent variance function, also the cross- and time-correlations between the observations. The weekly measurements from a zero-length and very short baseline are utilized to derive stochastic parameters. The impact on the AR and solution accuracy is analyzed for different positioning scenarios using the modified Kalman Filter. Comparing the positioning results obtained for the created model with respect to the results for the standard elevation-dependent model allows to conclude that the individual empirical stochastic model increases the accuracy of positioning solution and the efficiency of AR. The optimal solution is achieved for four-system Multi-GNSS solution using fully populated empirical model individual for satellite blocks, which provides a 2% increase in the effectiveness of the AR (up to 100%), an increase in the number of solutions with errors below 5 mm by 37% and a reduction in the maximum error by 6 mm compared to the Multi-GNSS solution using the elevation-dependent model with neglected measurements correlations.
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Vavilova, N. B., A. A. Golovan, A. V. Kozlov, I. A. Papusha, O. A. Zorina, E. A. Izmailov, S. E. Kukhtevich, and A. V. Fomichev. "INS/GNSS Integration with Account for Timing Skew and Displacement of GNSS Antenna. Experience of Practical Realization." Giroskopiya i Navigatsiya 29, no. 3 (2021): 52–68. http://dx.doi.org/10.17285/0869-7035.0070.

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We examine two aspects specific to complex data fusion algorithms in integrated strapdown inertial navigation systems aided by global positioning systems, with their inherent spatial separation between the GNSS antenna phase center and the inertial measurement unit, as well as with the timing skew between their measurements. The first aspect refers to modifications of mathematical models used in INS/GNSS integration. The second one relates to our experience in their application in onboard airborne navigation algorithms developed by Moscow Institute of Electromechanics and Automatics.
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Budzynski, Marcin, Kazimierz Jamroz, Jerzy Pyrchla, Wojciech Kustra, Adam Inglot, and Krzysztof Pyrchla. "Automated Parameter Determination for Horizontal Curves for the Purposes of Road Safety Models with the Use of the Global Positioning System." Geosciences 9, no. 9 (September 12, 2019): 397. http://dx.doi.org/10.3390/geosciences9090397.

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This paper presents the results of research conducted to develop an automated system capable of determining parameters for horizontal curves. The system presented in this article could calculate the actual course of a road by means of a two-stage positioning of recorded points along the road. In the first stage, measurements were taken with a Real-Time Network (RTN) receiver installed in a research vehicle. In the second stage, pictures from three cameras, also installed in the vehicle, were analyzed in order to correct the accuracy of the location of the measurement points along the road. The RTN messages and the pictures from the cameras were sent to a mobile workstation which integrated the received signals in an ArcGIS (Esri) environment. The system provides a way to quickly accumulate highly accurate data on the actual geometric parameters of a road. The computer scripts developed by the authors on the basis of the acquired data could automatically determine the parameters of the horizontal curves. The solution was tested in the field and some comments on its advantages and disadvantages are presented in this paper. The automation of data acquisition with regards to the run of a road provides effective data input for mathematical models that include the effect of horizontal curve parameters on road safety. These could be used to implement more effective ways of improving road safety.
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Dissertations / Theses on the topic "Global Positioning System – Mathematical models"

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Aloi, Daniel Nicholas. "Development and verification of a mathematical model to investigate the effects of earth-surface-based multipath reflections at a differential global positioning system ground reference site." Ohio : Ohio University, 1999. http://www.ohiolink.edu/etd/view.cgi?ohiou1175264170.

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Habarulema, John Bosco. "A contribution to TEC modelling over Southern Africa using GPS data." Thesis, Rhodes University, 2010. http://hdl.handle.net/10962/d1005241.

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Modelling ionospheric total electron content (TEC) is an important area of interest for radio wave propagation, geodesy, surveying, the understanding of space weather dynamics and error correction in relation to Global Navigation Satellite Systems (GNNS) applications. With the utilisation of improved ionosonde technology coupled with the use of GNSS, the response of technological systems due to changes in the ionosphere during both quiet and disturbed conditions can be historically inferred. TEC values are usually derived from GNSS measurements using mathematically intensive algorithms. However, the techniques used to estimate these TEC values depend heavily on the availability of near-real time GNSS data, and therefore, are sometimes unable to generate complete datasets. This thesis investigated possibilities for the modelling of TEC values derived from the South African Global Positioning System (GPS)receiver network using linear regression methods and artificial neural networks (NNs). GPS TEC values were derived using the Adjusted Spherical Harmonic Analysis (ASHA) algorithm. Considering TEC and the factors that influence its variability as “dependent and independent variables” respectively, the capabilities of linear regression methods and NNs for TEC modelling were first investigated using a small dataset from two GPS receiver stations. NN and regression models were separately developed and used to reproduce TEC fluctuations at different stations not included in the models’ development. For this purpose, TEC was modelled as a function of diurnal variation, seasonal variation, solar and magnetic activities. Comparative analysis showed that NN models provide predictions of GPS TEC that were an improvement on those predicted by the regression models developed. A separate study to empirically investigate the effects of solar wind on GPS TEC was carried out. Quantitative results indicated that solar wind does not have a significant influence on TEC variability. The final TEC simulation model developed makes use of the NN technique to find the relationship between historical TEC data variations and factors that are known to influence TEC variability (such as solar and magnetic activities, diurnal and seasonal variations and the geographical locations of the respective GPS stations) for the purposes of regional TEC modelling and mapping. The NN technique in conjunction with interpolation and extrapolation methods makes it possible to construct ionospheric TEC maps and to analyse the spatial and temporal TEC behaviour over Southern Africa. For independent validation, modelled TEC values were compared to ionosonde TEC and the International Reference Ionosphere (IRI) generated TEC values during both quiet and disturbed conditions. This thesis provides a comprehensive guide on the development of TEC models for predicting ionospheric variability over the South African region, and forms a significant contribution to ionospheric modelling efforts in Africa.
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Mama, Mounchili. "Mathematical Modelling of The Global Positioning System Tracking Signals." Thesis, Blekinge Tekniska Högskola, Avdelningen för matematik och naturvetenskap, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-4313.

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Recently, there has been increasing interest within the potential user community of Global Positioning System (GPS) for high precision navigation problems such as aircraft non precision approach, river and harbor navigation, real-time or kinematic surveying. In view of more and more GPS applications, the reliability of GPS is at this issue. The Global Positioning System (GPS) is a space-based radio navigation system that provides consistent positioning, navigation, and timing services to civilian users on a continuous worldwide basis. The GPS system receiver provides exact location and time information for an unlimited number of users in all weather, day and night, anywhere in the world. The work in this thesis will mainly focuss on how to model a Mathematical expression for tracking GPS Signal using Phase Locked Loop filter receiver. Mathematical formulation of the filter are of two types: the first order and the second order loops are tested successively in order to find out a compromised on which one best provide a zero steady state error that will likely minimize noise bandwidth to tracks frequency modulated signal and returns the phase comparator characteristic to the null point. Then the Z-transform is used to build a phase-locked loop in software for digitized data. Finally, a Numerical Methods approach is developed using either MATLAB or Mathematica containing the package for Gaussian elimination to provide the exact location or the tracking of a GPS in the space for a given a coarse/acquisition (C/A) code.
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Chadwell, C. David. "Investigation of stochastic models to improve the global positioning system satellite orbits /." The Ohio State University, 1995. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487861796818699.

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Wang, Jun. "Operating speed models for low speed urban environments based on in-vehicle GPS." Available online, Georgia Institute of Technology, 2006, 2006. http://etd.gatech.edu/theses/available/etd-03292006-111130/.

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Bruggemann, Troy Sterling. "Investigation of MEMS inertial sensors and aircraft dynamic models in global positioning system integrity monitoring for approaches with vertical guidance." Thesis, Queensland University of Technology, 2009. https://eprints.qut.edu.au/32050/1/Troy_Bruggemann_Thesis.pdf.

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An Approach with Vertical Guidance (APV) is an instrument approach procedure which provides horizontal and vertical guidance to a pilot on approach to landing in reduced visibility conditions. APV approaches can greatly reduce the safety risk to general aviation by improving the pilot’s situational awareness. In particular the incidence of Controlled Flight Into Terrain (CFIT) which has occurred in a number of fatal air crashes in general aviation over the past decade in Australia, can be reduced. APV approaches can also improve general aviation operations. If implemented at Australian airports, APV approach procedures are expected to bring a cost saving of millions of dollars to the economy due to fewer missed approaches, diversions and an increased safety benefit. The provision of accurate horizontal and vertical guidance is achievable using the Global Positioning System (GPS). Because aviation is a safety of life application, an aviation-certified GPS receiver must have integrity monitoring or augmentation to ensure that its navigation solution can be trusted. However, the difficulty with the current GPS satellite constellation alone meeting APV integrity requirements, the susceptibility of GPS to jamming or interference and the potential shortcomings of proposed augmentation solutions for Australia such as the Ground-based Regional Augmentation System (GRAS) justifies the investigation of Aircraft Based Augmentation Systems (ABAS) as an alternative integrity solution for general aviation. ABAS augments GPS with other sensors at the aircraft to help it meet the integrity requirements. Typical ABAS designs assume high quality inertial sensors to provide an accurate reference trajectory for Kalman filters. Unfortunately high-quality inertial sensors are too expensive for general aviation. In contrast to these approaches the purpose of this research is to investigate fusing GPS with lower-cost Micro-Electro-Mechanical System (MEMS) Inertial Measurement Units (IMU) and a mathematical model of aircraft dynamics, referred to as an Aircraft Dynamic Model (ADM) in this thesis. Using a model of aircraft dynamics in navigation systems has been studied before in the available literature and shown to be useful particularly for aiding inertial coasting or attitude determination. In contrast to these applications, this thesis investigates its use in ABAS. This thesis presents an ABAS architecture concept which makes use of a MEMS IMU and ADM, named the General Aviation GPS Integrity System (GAGIS) for convenience. GAGIS includes a GPS, MEMS IMU, ADM, a bank of Extended Kalman Filters (EKF) and uses the Normalized Solution Separation (NSS) method for fault detection. The GPS, IMU and ADM information is fused together in a tightly-coupled configuration, with frequent GPS updates applied to correct the IMU and ADM. The use of both IMU and ADM allows for a number of different possible configurations. Three are investigated in this thesis; a GPS-IMU EKF, a GPS-ADM EKF and a GPS-IMU-ADM EKF. The integrity monitoring performance of the GPS-IMU EKF, GPS-ADM EKF and GPS-IMU-ADM EKF architectures are compared against each other and against a stand-alone GPS architecture in a series of computer simulation tests of an APV approach. Typical GPS, IMU, ADM and environmental errors are simulated. The simulation results show the GPS integrity monitoring performance achievable by augmenting GPS with an ADM and low-cost IMU for a general aviation aircraft on an APV approach. A contribution to research is made in determining whether a low-cost IMU or ADM can provide improved integrity monitoring performance over stand-alone GPS. It is found that a reduction of approximately 50% in protection levels is possible using the GPS-IMU EKF or GPS-ADM EKF as well as faster detection of a slowly growing ramp fault on a GPS pseudorange measurement. A second contribution is made in determining how augmenting GPS with an ADM compares to using a low-cost IMU. By comparing the results for the GPS-ADM EKF against the GPS-IMU EKF it is found that protection levels for the GPS-ADM EKF were only approximately 2% higher. This indicates that the GPS-ADM EKF may potentially replace the GPS-IMU EKF for integrity monitoring should the IMU ever fail. In this way the ADM may contribute to the navigation system robustness and redundancy. To investigate this further, a third contribution is made in determining whether or not the ADM can function as an IMU replacement to improve navigation system redundancy by investigating the case of three IMU accelerometers failing. It is found that the failed IMU measurements may be supplemented by the ADM and adequate integrity monitoring performance achieved. Besides treating the IMU and ADM separately as in the GPS-IMU EKF and GPS-ADM EKF, a fourth contribution is made in investigating the possibility of fusing the IMU and ADM information together to achieve greater performance than either alone. This is investigated using the GPS-IMU-ADM EKF. It is found that the GPS-IMU-ADM EKF can achieve protection levels approximately 3% lower in the horizontal and 6% lower in the vertical than a GPS-IMU EKF. However this small improvement may not justify the complexity of fusing the IMU with an ADM in practical systems. Affordable ABAS in general aviation may enhance existing GPS-only fault detection solutions or help overcome any outages in augmentation systems such as the Ground-based Regional Augmentation System (GRAS). Countries such as Australia which currently do not have an augmentation solution for general aviation could especially benefit from the economic savings and safety benefits of satellite navigation-based APV approaches.
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Wang, Jun. "Operating Speed Models for Low Speed Urban Enviroments based on In-Vehcile GPS." Diss., Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/10508.

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Low speed urban streets are designed to provide both access and mobility, and accommodate multiple road users, such as bicyclists and pedestrians. However, speeds on these facilities often exceed the intended operating speeds as well as their design speeds. Several studies have indicated that the design speed concept, as implemented in the roadway design process in the United States, does not guarantee a consistent alignment that promotes uniform operating speeds less than design speeds. To overcome these apparent shortfalls of the design speed approach, a promising design approach is a performance-based design procedure with the incorporation of operating speeds. Under this procedure, the geometric parameters of the roadways are selected based on their influences on the desired operating speeds. However, this approach requires a clear understanding of the relationships between operating speeds and various road environments. Although numerous studies have developed operating speed models, most of these previous studies have concentrated on high speed rural two-lane highways. In contrast, highway designers and planners have very little information regarding the influence of low speed urban street environments on drivers' speeds. This dissertation investigated the relationship between drivers' speed choices and their associated low speed urban roadway environments by analyzing second-by-second in-vehicle GPS data from over 200 randomly selected vehicles in the Atlanta, Georgia area. The author developed operating speed models for low speed urban street segments based on roadway alignment, cross-section characteristics, roadside features, and adjacent land uses. The author found the number of lanes per direction of travel had the most significant influence on drivers' speeds on urban streets. Other significant variables include on-street parking, sidewalk presence, roadside object density and offset, T-intersection and driveway density, raised curb, and adjacent land use. The results of this research effort can help highway designers and planners better understand expected operating speeds when they design and evaluate low speed urban roadways.
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Chandler, Shawn Aaron. "Global Time-Independent Agent-Based Simulation for Transactive Energy System Dispatch and Schedule Forecasting." PDXScholar, 2015. https://pdxscholar.library.pdx.edu/open_access_etds/2212.

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Electricity service providers (ESP) worldwide have increased their interest in the use of electrical distribution, transmission, generation, storage, and responsive load resources as integrated systems. Referred to commonly as "smart grid," their interest is driven by widespread goals to improve the operations, management and control of large-scale power systems. In this thesis I provide research into a novel agent-based simulation (ABS) approach for exploring smart grid system (SGS) dispatch, schedule forecasting and resource coordination. I model an electrical grid and its assets as an adaptive ABS, assigning an agent construct to every SGS resource including demand response, energy storage, and distributed generation assets. Importantly, real time is represented as an environment variable within the simulation, such that each resource is characterized temporally by multiple agents that reside in different times. The simulation contains at least as many agents per resource as there are time intervals being investigated. These agents may communicate with each other during the simulation, but only agents assigned to represent the same unique resource may exchange information between time periods. Thus, confined within each time interval, each resource agent may also interact with other resource agents. As with any agent-based model, the agents may also interact with the environment, in this case, containing forecasted environment, load and price information specific to each time interval. The resulting model is a time-independent global approach capable of: (1) capturing time-variant local grid conditions and distribution grid load balancing constraints; (2) capturing time-variant resource availability and price constraints, and finally, (3) simulating efficient unit-commitment real-time dispatches and schedule forecasts considering time-variant forecasted transactive market prices. This thesis details the need for such a system, discusses the form of the ABS, and analyzes the predictive behavior of the model through a critical lens by applying the resulting proof-of-concept simulation to a set of comprehensive validation scenarios. The resulting analysis demonstrates ABS as an effective tool for real-time dispatch and SGS schedule forecasting as applied to research, short-term economic operations planning and transactive systems alike. The model is shown to converge on economic opportunities regardless of the price or load-forecast shape and to correctly perform least-cost dispatch and schedule forecasting functionality.
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Feng, Lujia. "Investigations of volcanic and earthquake-related deformation: observations and models from Long Valley Caldera, Northwestern Peloponnese, and Northwestern Costa Rica." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/41220.

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The advent of Global Positioning System (GPS) has revolutionized geodesy with high accuracy, fast speed, simple use, and low cost. This dissertation investigates three topics on volcano and earthquake-related deformation using GPS measurements and models to demonstrate the power of the new generation of geodetic methods. The three topics include the 2002-2003 continued episodic inflation at Long Valley Caldera in eastern California, the coseismic and postseismic response of the energetic 2008 MW 6.4 Achaia-Elia Earthquake in northwest Peloponnese, Greece, and the interseismic megathrust coupling and forearc sliver transport near the Nicoya Peninsula in northwest Costa Rica.
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Ahmed, Hasim Abdalla Obaid. "Construction and analysis of efficient numerical methods to solve Mathematical models of TB and HIV co-infection." Thesis, University of the Western Cape, 2011. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_3704_1325661141.

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In this thesis, we study these models and design and analyze robust numerical methods to solve them. To proceed in this direction, first we study the sub-models and then the full model. The first sub-model describes the transmission dynamics of HIV that accounts for behavior change. The impact of HIV educational campaigns is also studied. Further, we explore the effects of behavior change and different responses of individuals to educational campaigns in a situation where individuals may not react immediately to these campaigns. This is done by considering a distributed time delay in the HIV sub-model. This leads to Hopf bifurcations around the endemic equilibria of the model. These bifurcations correspond to the existence of periodic solutions that oscillate around the equilibria at given thresholds. Further, we show how the delay can result in more HIV infections causing more increase in the HIV prevalence. Part of this study is then extended to study a co-infection model of HIV-TB. A thorough bifurcation analysis is carried out for this model. Robust numerical methods are then designed and analyzed for these models. Comparative numerical results are also provided for each model.
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Books on the topic "Global Positioning System – Mathematical models"

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Melbourne, William G. A fully redundant double difference algorithm for obtaining minimum variance estimates from GPS observations. Pasadena, Calif: National Aeronautics and Space Administration, Jet Propulsion Laboratory, California Institute of Technology, 1986.

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Han, Shaowei. Carrier phase-based long-range GPS kinematic positioning. Sydney, NSW, Australia: University of New South Wales, 1997.

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Landau, Herbert. Zur Nutzung des Global Positioning Systems in Geodäsie und Geodynamik: Modellbildung, Software-Entwicklung und Analyse. Neubiberg: Studiengang Vermessungswesen, Universität der Bundeswehr München, 1988.

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Günther, Klein. Arbeiten zum Thema 'Inertialschwere'. München: Verlag der Bayerischen Akademie der Wissenschaften, 1990.

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Amiri-Simkooei, AliReza. Variance Component Estimation In Linear Models: Theoretical And Practical Aspects On Global Positioning System. Saarbrücken , Germany: VDM Verlag Dr. Müller, 2010.

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Shmaliy, Yuriy S. GPS-based optimal FIR filtering of clock models. New York: Nova Science Publishers, 2009.

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Shmaliy, Yuriy S. GPS-based optimal FIR filtering of clock models. Hauppauge, NY, USA: Nova Science Publishers, 2009.

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Memarzadeh, Y. Ionospheric modeling for precise GNSS applications. Delft: Nederlandse Commissie voor Geodesie = Netherlands Geodetic Commission, 2009.

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Kleijer, Frank. Troposphere modeling and filtering for precise GPS leveling. Delft: Nederlandse Comissie voor Geodesie, 2004.

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Canada, Canada Environment. Modelling the global climate system. Ottawa: Environment Canada, 1994.

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Book chapters on the topic "Global Positioning System – Mathematical models"

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Hofmann-Wellenhof, Bernhard, Herbert Lichtenegger, and James Collins. "Mathematical models for positioning." In Global Positioning System, 159–77. Vienna: Springer Vienna, 1992. http://dx.doi.org/10.1007/978-3-7091-5126-6_8.

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Hofmann-Wellenhof, Bernhard, Herbert Lichtenegger, and James Collins. "Mathematical models for positioning." In Global Positioning System, 181–200. Vienna: Springer Vienna, 1997. http://dx.doi.org/10.1007/978-3-7091-3297-5_8.

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Hofmann-Wellenhof, Bernhard, Herbert Lichtenegger, and James Collins. "Mathematical models for positioning." In Global Positioning System, 179–97. Vienna: Springer Vienna, 1994. http://dx.doi.org/10.1007/978-3-7091-3311-8_8.

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Hofmann-Wellenhof, Bernhard, Herbert Lichtenegger, and James Collins. "Mathematical models for positioning." In Global Positioning System, 181–202. Vienna: Springer Vienna, 2001. http://dx.doi.org/10.1007/978-3-7091-6199-9_8.

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Wei, M., and K. P. Schwarz. "A Discussion of Models for GPS/INS Integration." In Global Positioning System: An Overview, 316–27. New York, NY: Springer New York, 1990. http://dx.doi.org/10.1007/978-1-4615-7111-7_30.

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Woodhouse, Stephen, and Mostyn Brown. "The Impact of Digitalization." In The Palgrave Handbook of International Energy Economics, 613–27. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-86884-0_30.

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AbstractPrevious energy transformations have been driven by the exploitation of a new energy resource. In contrast, although the digitalization of energy is delivering cost reductions in the supply and transportation of energy; digitalization is truly transformational because it brings the demand side into play, facilitating the move to a more integrated, highly flexible and customer-centric energy system which will ultimately unlock deep decarbonization of our societies. This fertile new energy landscape will be dominated by data-rich organizations able to establish direct relationships with consumers, resulting in the provision of new services which enable the integration of energy consumption with weather-dependent renewable production. Much of the focus is on the intelligent management of demand and supply from connected buildings and electric vehicles, leading to a proliferation of new business models. This increased connectivity comes with risks: increased danger of cybersecurity attacks and disruption of existing business relationships, staffing and organizational structures and a re-positioning of the role of the customer at the heart of the system. This commercial disruption is inherent to the digital transformation of the energy sector: an essential step in the transition to a carbon-neutral global economy.
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"Appendix B: Global Positioning System Position Velocity and Acceleration Filter Error Model." In Applied Mathematics in Integrated Navigation Systems, Third Edition, 313–14. Reston ,VA: American Institute of Aeronautics and Astronautics, 2007. http://dx.doi.org/10.2514/5.9781600861598.0313.0314.

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Adamchuk, Viacheslav, Bradley S. Barker, Gwen Nugent, Neal Grandgenett, Megan Patent-Nygren, Collin Lutz, and Kathy Morgan. "Learning Geospatial Concepts as Part of a Non-Formal Education Robotics Experience." In Geographic Information Systems, 1368–84. IGI Global, 2013. http://dx.doi.org/10.4018/978-1-4666-2038-4.ch082.

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In the increasingly modern and technological world, it has become common to use global navigation satellite system (GNSS), such as Global Positioning System (GPS), receivers, and Geographic Information Systems (GIS) in everyday life. GPS-equipped mobile devices and various Web services help users worldwide to determine their locations in real-time and to explore unfamiliar land areas using virtual tools. From the beginning, geospatial technologies have been driven by the need to make efficient use of natural resources. More recently, GPS-equipped autonomous vehicles and aircraft have been under development to facilitate technological processes, such as agricultural operations, transportation, or scouting, with limited or virtual human control. As outdoor robotics relies upon a number of principles related to science, technology, engineering, and mathematics (STEM), using such an instructional context for non-formal education has been promising. As a result, the Geospatial and Robotics Technologies for the 21st Century program discussed in this chapter integrates educational robotics and GPS/GIS technologies to provide educational experiences through summer camps, 4-H clubs, and afterschool programs. The project’s impact was assessed in terms of: a) youth learning of computer programming, mathematics, geospatial and engineering/robotics concepts as well as b) youth attitudes and motivation towards STEM-related disciplines. An increase in robotics, GPS, and GIS learning questionnaire scores and a stronger self-efficacy in relevant STEM areas have been found through a set of project-related assessment instruments.
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"An Applied Mathematical Model for Business Transformation and Enterprise Architecture." In Using Applied Mathematical Models for Business Transformation, 340–76. IGI Global, 2020. http://dx.doi.org/10.4018/978-1-7998-1009-4.ch010.

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The business and societal transformation project (B&STP) of a modern business and global environment needs a well-designed holistic global security management system (HGSMS) that, in turn, depends on measurable success factors; these factors are used for the evolution of the transformation process. During the last decade, due to the global insecurity and financial crisis, the security strategies were not efficient. That is mainly due to the fact that businesses depend on security standards, law, cyber and information technology evolution, enterprise architecture, business engineering, and multilevel interoperability. They are restricted to blindfolded infrastructure security operations and/or martial like legal cases. Major B&STPs are brutally wrecked by various security violations that may cause a no-go decision. Most of such security misfits are used for internal politics, while highly important issues and teams' problems are simply ignored.
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"An Applied Mathematical Model for Business Transformation and Enterprise Architecture." In Using Applied Mathematical Models for Business Transformation, 172–210. IGI Global, 2020. http://dx.doi.org/10.4018/978-1-7998-1009-4.ch006.

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This chapter proposes a cross-business domain holistic mathematical model (HMM) that is the result of a lifetime of research on business transformations, applied mathematics, software modelling, business engineering, financial analysis, and global enterprise architecture. This research is based on an authentic and proprietary mixed research method that is supported by an underlining mainly qualitative holistic reasoning model module. The proposed HMM formalism attempts to mimic some functions of the human brain, which uses empirical processes that are mainly based on the beam-search, like heuristic decision-making process. The HMM can be used to implement a decision-making system or an expert system that can integrate the enterprise's business, information, and communication technology environments.
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Conference papers on the topic "Global Positioning System – Mathematical models"

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Pai, B. Voon, W. A. W. Z. Abidin, H. Zen, T. Masri, and M. Abdullah. "Open space mathematical model for the mobile satellite L-band signal in Sarawak using Global Positioning System technology." In 2011 International Conference on Space Science and Communication (IconSpace). IEEE, 2011. http://dx.doi.org/10.1109/iconspace.2011.6015885.

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Ranganathan, Jaganathan, and William H. Semke. "Three-Axis Gimbal Surveillance Algorithms for Use in Small UAS." In ASME 2008 International Mechanical Engineering Congress and Exposition. ASMEDC, 2008. http://dx.doi.org/10.1115/imece2008-67667.

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An active three-axis gimbal system is developed to allow small fixed wing Unmanned Aircraft Systems (UAS) platforms to estimate accurate position information by pointing at a target and also to track a known target location. Specific targets vary from a stationary point on the ground to aircraft in the national airspace. The payload developed to accomplish this at the University of North Dakota is the Surveillance by University of North Dakota Observational Gimbal (SUNDOG). This paper will focus on a novel, nonlinear closed form analytical algorithm developed to calculate the exact rotation angles for a three-axis gimbal system to point a digital imaging sensor at a target, as well as how to estimate accurate position of a target by using the pointing angles of a three-axis gimbal system. A kinematic analysis is done on a three-axis gimbal system to get the appropriate model of gimbal rotations in order to point at a certain location on the ground. The mathematical model includes an inertial coordinate system that has coordinates fixed to the Earth, a coordinate system that is body-fixed to the aircraft, and a third coordinate system that is fixed to the gimbal. Therefore, multiple three-dimensional transformations are required to accurately provide the necessary pointing angles to the gimbal system. The autonomous control system uses Global Positioning System (GPS), Inertial Measurement Unit (IMU), and other sensor data to estimate position and attitude during flight. Since the algorithm is entirely based on Inertial Measurement Unit (IMU) and Global Positioning System (GPS) device inputs, any error from these devices cause offset in the target location. Hence, an error analysis is carried out to find the offset distance and the operating range of the algorithm. The main advantage obtained in the three-axis gimbal system is that the orientation of the image will always be aligned in a specified direction for effective interpretation. The closed form expressions to the non-linear transformations provide simple solutions easily programmed without large computational expense. Experimental work will be carried out in a controlled environment and in flight testing to show the autonomous tracking ability of the gimbal system. Simulation and experimental data illustrating the effectiveness of the surveillance algorithms is presented.
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Sahoo, Shubhashisa, Shankar C. Subramanian, and Suresh Srivastava. "Sensitivity Analysis of Vehicle Parameters for Heading Angle Control of an Unmanned Ground Vehicle." In ASME 2014 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/imece2014-39685.

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Even if there are many software and mathematical models available in the literature to analyze the dynamic performance of Unmanned Ground Vehicles (UGVs), it is always difficult to identify or collect the required vehicle parameters from the vehicle manufacturer for simulation. In analyzing the vehicle handling performance, a difficult and complex task is to use an appropriate tire model that can accurately characterize the ground-wheel interaction. Though, the well-known ‘Magic Formula’ is widely used for this purpose, it requires expensive test equipment to estimate the Magic Formula coefficients. The design of longitudinal and lateral controllers plays a significant role in path tracking of an UGV. Though the speed of the vehicle may remain almost constant in most of the maneuvers such as lane change, Double Lane Change (DLC), step steer, cornering, etc., design of the lateral controller is always a challenging task as it depends on the vehicle parameters, road information and also on the steering actuator dynamics. Although a mathematical model is an abstraction of the actual system, the controller is designed based on this model and then deployed on the real system. In this paper, a realistic mathematical model of the vehicle considering the steering actuator dynamics has been developed by calculating the cornering stiffnesses from the basic tire information and the vertical load on each tire. A heading angle controller of the UGV has been considered using the Point-to-Point navigation algorithm. Then, these controllers have been implemented on a test platform equipped with an Inertial Measurement Unit (IMU) and a Global Positioning System (GPS). A wide range of experiments such as J-Turn, lane change and DLC have also been conducted for comparison with the simulation results. Sensitivity analysis has been carried out to check the robustness and stability of the controller by varying the cornering stiffness of tires, the most uncertain parameter. The longitudinal speed of the vehicle is assumed to vary between a minimum value of 1.4 m/s and a maximum value of 20 m/s. It has been found that when the vehicle is moving at a constant velocity of 3.2 m/s, a heading angle change of 20 degrees can be achieved within 3 seconds with 2% steady state error using a proportional controller. It was observed that at lower speeds, the controller is more sensitive to the steering actuator dynamics and at higher speeds, the controller is more sensitive to the cornering stiffness of tires.
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Prescott, Jonathan, Curtis Patterson, and Arfeen Najeeb. "Use of Inertial Measurement Unit In-Line Inspection Data to Support Code Stress Compliance and Integrity Evaluations." In 2022 14th International Pipeline Conference. American Society of Mechanical Engineers, 2022. http://dx.doi.org/10.1115/ipc2022-87046.

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Abstract Pipelines are an essential segment of infrastructure required to transport a variety of products to markets in our economies. The integrity and safe operation of those pipeline necessitates that pipeline operators have a thorough understanding of their pipeline systems, their configuration, and the changing operating condition within their pipeline networks. Inertial measurement unit (IMU), a technology that can measure the angular rate and acceleration and when combined with global positioning and navigation equipment such as pipeline above ground markers, can calculate position and orientation with 6 degrees of freedom: x, y, z, and pitch, roll, and yaw. IMU launched within the pipeline via in-line inspection tool trains, can be used to develop accurate three-dimensional geometry of the pipelines they inspect. This information can be used to confirm the geometry of the pipeline (i.e. degree of roping, bend angle, bend radius, and other abnormalities observed within the generated centerline from the inspection based on conventional construction practices). Therefore, the application of IMU technology within pipeline design and integrity work can be a useful tool in providing the necessary input information which can support ongoing studies such as verification of maximum operating thermal differentials which can be imposed on a pipeline to remain compliant with governing pipeline codes, and/or the information can be used to perform gap analysis studies with other integrity records (alignment sheets, as-built pipe tallies), or to support other pipeline integrity evaluations. When IMU data is processed with mathematical techniques essential information from IMU data can be obtained such as bend angle, bend radius, and degree of installed curvature. A case study showing the results of the application of processed IMU data for as-built evaluation is presented and its use to help support a variety of decision making is discussed. The IMU data is a key data input when constructing detailed finite element models for on-going stress analysis studies.
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Gullicks, Jason G., and William H. Semke. "Analytical and Experimental Analysis of a Precision Positioning Actuator System." In ASME 2004 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2004. http://dx.doi.org/10.1115/detc2004-57325.

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An innovative flexure design concept is developed that involves the use of composite materials with bonded piezoelectric actuators to create a “smart actuator” for nanometer scale positioning both in and out of plane. The utilization of smart actuators/sensors will have many benefits over current positioning stages including the utilization of advantageous composite properties, the increase of the resonant frequency of the stage system, the simplification of the manufacturing procedure, and possible increased range of motion. Enhanced mechanical response is made possible by using composite materials and proper layer orientation. This work is a “proof of concept” design for the ultra-precision smart actuator. Analytical and numerical models were developed to determine the response of the composite material and piezoelectric actuator system. Experimentation was performed on the system to verify the results of the mathematical and numerical models. Good correlation between mathematical, numerical, and experimental data was seen in axial and bending modes of operation. Results from the parametric and experimental verification studies are presented to illustrate the efficacy of the design concept.
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Han, Y., and H. S. Tzou. "Nano-and Micro-Actuations of Hard Disk’s Head Positioning System: Actuator Design and Evaluation of Performance." In ASME 2006 International Mechanical Engineering Congress and Exposition. ASMEDC, 2006. http://dx.doi.org/10.1115/imece2006-14724.

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High-density magnetic hard disks are key components in information storage. In high-density hard disk drives (HDD), both super fast track seeking and extremely accurate positioning of the read/write head are required. A new multiDOF piezoelectric micro-actuator with nano-transverse and micro-lateral control of the head positioning system for highdensity hard disk drives is proposed. For the track following control of a head positioning system in the HDD, proper modeling of the system including the voice coil motor (VCM), suspension, slider, and gimbal system is very important. Before further comprehensive analysis of the whole assembly, the design concept and the evaluation of the micro-actuator are focused on in this paper. First, design of the new piezoelectric micro-actuator is illustrated. The design of the new micro-actuator is based on the axial deformation of piezoelectric elements for lateral motion control and the bimorph actuation of piezoelectric elements for transverse nm motion control. Next, mathematical models of the micro-actuator system are defined. Lastly, the micro-actuator system is modeled using the commercial finite element package ANSYS. The results from analytical analysis and FE analysis are compared. Static response of the micro-actuator system is evaluated first, followed by analysis of dynamic response analysis. Static actuations of the new actuator system satisfy both lateral (±0.1μm) and transverse (15nm) specifications. Dynamic analysis of the ultra-precision system suggests that the new piezoelectric micro-actuator improves performance of highdensity hard disk drives by increasing servo bandwidth and decreasing flying height.
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Misankova, Maria, Jana Kliestikova, Anna Krizanova, and Tatiana Corejova. "Brand Value Assessment in Terms of Contemporary Global Challenges." In Contemporary Issues in Business, Management and Education. Vilnius Gediminas Technical University, 2017. http://dx.doi.org/10.3846/cbme.2017.065.

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Brand represents one of the most important assets of the company. Brand-managing activities are typically related to brand positioning and integration with marketing campaigns, and can involve complex decisions. The branding of an organization is indeed a dynamic system with many cause-effect relationships as well as intangible and heterogeneous variables. In order to assess the value of individual brands can be used various models developed worldwide, based on different input data and valuation methodologies. We assume that individual environment in which company operates and consumers’ perceptions in different countries influence the ability and usability of these models in other countries. Therefore, we applied chosen well-known brand value models on the set of Slovak companies and validated their assessment ability in specific condition of the Slovak Republic. This was provided by the critical comparison of calculated values with the official values of brands of these companies listed in the Slovak journal. Through this, we pointed out the importance of the development of unique brand value model, which will be constructed in the specific condition of individual countries and highlight the weak assessment ability of foreign models.
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Nakao, Yohichi, Hajime Niimiya, and Takuya Obayashi. "Design of Rotary-Type Flow Control Valve for Control of Water-Driven Spindle." In ASME 2010 International Mechanical Engineering Congress and Exposition. ASMEDC, 2010. http://dx.doi.org/10.1115/imece2010-37830.

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Water-driven spindle was developed for producing small and precise parts by the diamond turning processes. Rotational speed of the spindle can be controlled by the flowrate supplied to the spindle. The paper describes a newly developed rotary-type flow control valve that is designed for controlling rotational speed of the water-driven spindle. In particular, the paper focuses on the establishment of the mathematical model capable of representing the characteristics of the open loop control system composed of the pump, flow control valve and spindle. Mathematical models are then derived so that a feedback control system can be designed using the models. Performances of the flow control valve and the spindle are examined through simulation as well as experiments. It is then verified that the derived mathematical models are capable of representing the performance of the system. In addition, the required positioning accuracy of valve rotation for achieving desired control of the rotational speed of the spindle is considered based on the derived linearized mathematical model.
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Tannuri, Eduardo A., Helio M. Morishita, Vinicius L. M. Veras, and Glenan A. Lago. "Critical Analysis of Control and Filtering Algorithms Used in Real Dynamic Positioning Systems." In ASME 2005 24th International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2005. http://dx.doi.org/10.1115/omae2005-67137.

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Dynamic positioning systems (DPS) comprise the utilization of active propulsion to maintain the position and heading of a vessel. Sensors are used to measure the actual position of the floating body, and a control algorithm is responsible for the calculation of forces to be applied to each propeller, in order to counteract all environmental forces, including wind, waves and current loads. The controller cannot directly compensate motions in the sea waves frequency range, since they would require an enormous power to be attenuated, possibly causing damage to the propeller system. A filtering algorithm is then used to separate high frequency components from the low frequency ones, which are indeed controlled. Usual commercial systems apply Kalman filtering technique to perform such task, which includes a full model of the system. Furthermore, an adaptive on-line estimation algorithm is also used to evaluate the wave peak frequency, since the model in Kalman Filter depends on such parameter. The controller itself is based on a simple proportional-derivative (PD) actions. This paper presents all the mathematical formulation of the Kalman Filter, adaptive algorithm and the controller used in commercial DPS and performs a critical analysis of those models. Some illustrative results of a dynamic positioned shuttle vessel are presented, considering the incidence of waves, current and winds.
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Ballarini, Roberto, and Shamim Ahmed. "Local-Global Analysis of Crack Growth in Continuously Reinforced Ceramic Matrix Composites." In ASME 1989 International Gas Turbine and Aeroengine Congress and Exposition. American Society of Mechanical Engineers, 1989. http://dx.doi.org/10.1115/89-gt-138.

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This paper describes the development of a mathematical model for predicting the strength and micro-mechanical failure characteristics of continuously reinforced ceramic matrix composites. The local-global analysis models the vicinity of a propagating crack tip as a local heterogeneous region (LHR) consisting of spring-like representation of the matrix, fibers and interfaces. This region is embedded in an anisotropic continuum (representing the bulk composite) which is modeled by conventional finite elements. Parametric studies are conducted to investigate the effects of LHR size, component properties, interface conditions, etc. on the strength and sequence of the failure processes in the unidirectional composite system. The results are compared with those predicted by the models developed by Marshall et al. (1985) and by Budiansky et al. (1986).
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