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The purpose of this paper is to discuss and evaluate the performances of the ionospheric delays for spaceborne global positioning system (GPS) receivers with changing altitudes, and to calculate the scale factors and receiver differential code biases (DCBs). Ionospheric delay is one of the major error sources in GPS positioning.

The fractional total electron content (TEC) above the receiver was obtained from the TEC above the Earth and a scale factor. Methods to determine scale factors were implemented and further developed, based on global ionospheric maps (GIM), Klobuchar model and modified Klobuchar model. Receiver DCB values were achieved at the same time. Methods were validated using flight data from the Gravity Recovery and Climate Experiment mission.

Scale factors are influenced by the receiver altitude, TECs along the line of sight and the ionospheric correction method. In a given case, scale factors obtained using GIM are more regular, whereas those obtained using Klobuchar model and modified Klobuchar model are closely related to TECs. DCBs obtained using GIM method are larger than those obtained using Klobuchar model and modified Klobuchar model.

With scale factors and receiver DCBs, accuracy of GPS positioning solutions can be improved, which are useful for spaceborne engineering applications.

The purpose of this paper is to discuss the applicability of Global Positioning System (GPS) ionospheric delay correction models. Ionospheric delay is the most influential error source in GPS positioning, and ionospheric refraction is difficult to be corrected by dual frequency measurement for the common single frequency GPS receivers. Generally, ionospheric models are employed to correct errors. In order to analyze the ionospheric influence to GPS signals and the accuracy and adaptability of GPS ionospheric error correction models a quantificational analysis for ionospheric error correction models is absolutely necessary.

On the base of the mechanism of ionospheric error, the Klobuchar model that is widely used and actual measured correction model (including local and global ionospheric error correction models) are analyzed in detail. With the data about ionosphere obtained from GPS authority Crustal Dynamics Data Information System, the precision and adaptability of two kinds of ionospheric error correction model are validated, and a predigested method of investigating precision of local ionospheric error correction model is presented.

Klobuchar model has higher precision in middle or low latitude than in high latitude, and ionospheric delay fluctuates acutely in a day with a day‐cycle. Ionospheric delay varies as the latitude changes: ionospheric delay is largest around equator and smallest in the areas of two poles, which shows symmetry. The relationship between ionospheric delay and longitude is similar to the relationship between ionospheric delay and latitude. The fitting model has better effect than Klobuchar model.

This paper thoroughly researches GPS ionospheric error correction models. The conclusions are presented for the selection of GPS correction models, that it is useful for practical engineering application and will be the theoretic foundation for the improvement of the GPS accurate positioning.

The purpose of this paper is based on implementation of Global Navigation Satellite System (GNSS) technique in civil aviation for recovery of aircraft position using Single Point Positioning (SPP) method in kinematic mode.

The aircraft coordinates in ellipsoidal frame were obtained based on Global Positioning System (GPS) code observations for SPP method. The numerical computations were executed in post-processing mode in the Aircraft Positioning Software (APS) package. The mathematical scheme of equation observation of SPP method was solved using least square estimation in stochastic processing. In the experiment, airborne test using Cessna 172 aircraft on September 07, 2011 in the civil aerodrome in Mielec was realized. The aircraft position was recovery using observations data from Topcon HiperPro dual-frequency receiver with interval of 1 second.

In this paper, the average value of standard deviation of aircraft position is about 0.8 m for Latitude, 0.7 m for Longitude and 1.5 m for ellipsoidal height, respectively. In case of the Mean Radial Spherical Error (MRSE) parameter, the average value equals to 1.8 m. The standard deviation of receiver clock bias was presented in this paper and the average value amounts to 34.4 ns. In this paper, the safety protection levels of Horizontal Protection Level (HPL) and Vertical Protection Level (VPL) were also showed and described.

In this paper, the analysis of aircraft positioning is focused on application the least square estimation in SPP method. The Kalman filtering operation can be also applied in SPP method for designation the position of the aircraft.

The SPP method can be applied in civil aviation for designation the position of the aircraft in Non-Precision Approach (NPA) GNSS procedure at the landing phase. The typical accuracy of aircraft position is better than 220 m for lateral navigation in NPA GNSS procedure. The limit of accuracy of aircraft position in vertical plane in NPA GNSS procedure is not available.

This paper is destined for people who works in the area of aviation and air transport.

The work presents that SPP method as a universal technique for recovery of aircraft position in civil aviation, and this method can be also used in positioning of aircraft based on Global Navigation Satellite System (GLONASS) code observations.

The purpose of this paper is to present the problem of implementation of the differential global navigation satellite system (DGNSS) differential technique for aircraft accuracy positioning. The paper particularly focuses on identification and an analysis of the accuracy of aircraft positioning for the DGNSS measuring technique.

The investigation uses the DGNSS method of positioning, which is based on using the model of single code differences for global navigation satellite system (GNSS) observations. In the research experiment, the authors used single-frequency code observations in the global positioning system (GPS)/global navigation satellite system (GLONASS) system from the on-board receiver Topcon HiperPro and the reference station REF1 (reference station for the airport military EPDE in Deblin in south-eastern Poland). The geodetic Topcon HiperPro receiver was installed in Cessna 172 plane in the aviation test. The paper presents the new methodology in the DGNSS solution in air navigation. The aircraft position was estimated using a “weighted mean” scheme for differential global positioning system and differential global navigation satellite system solution, respectively. The final resultant position of aircraft was compared with precise real-time kinematic – on the fly solution.

In the investigations it was specified that the average accuracy of positioning the aircraft Cessna 172 in the geocentric coordinates XYZ equals approximately: +0.03 ÷ +0.33 m along the x-axis, −0.02 ÷ +0.14 m along the y-axis and approximately +0.02 ÷ −0.15 m along the z-axis. Moreover, the root mean square errors determining the measure of the accuracy of positioning of the Cessna 172 for the DGNSS differential technique in the geocentric coordinates XYZ, are below 1.2 m.

In research, the data from GNSS onboard receiver and also GNSS reference receiver are needed. In addition, the pseudo-range corrections from the base stations were applied in the observation model of the DGNSS solution.

The presented research method can be used in a ground based augmentation system (GBAS) augmentation system, whereas the GBAS system is still not applied in Polish aviation.

The paper is destined for people who work in the area of aviation and air transport.

The study presents the DGNSS differential technique as a precise method for recovery of aircraft position in civil aviation and this method can be also used in the positioning of aircraft based on GPS and GLONASS code observations.

This paper aims to present the problem of the integration of the global positioning system (GPS)/global navigation satellite system (GLONASS) data for the processing of aircraft position determination.

The aircraft coordinates were obtained based on GPS and GLONASS code observations for the single point positioning (SPP) method. The numerical computations were executed in the aircraft positioning software (APS) package. The mathematical scheme of equation observation of the SPP method was solved using least square estimation in stochastic processing. In the research experiment, the raw global navigation satellite system data from the Topcon HiperPro onboard receiver were applied.

In the paper, the mean errors of an aircraft position from APS were under 3 m. In addition, the accuracy of aircraft positioning was better than 6 m. The integrity term for horizontal protection level and vertical protection level parameters in the flight test was below 16 m.

The paper presents only the application of GPS/GLONASS observations in aviation, without satellite data from other navigation systems.

The presented research method can be used in an aircraft based augmentation system in Polish aviation.

The paper is addressed to persons who work in aviation and air transport.

The paper presents the SPP method as a satellite technique for the recovery of an aircraft position in an aviation test.

The purpose of this paper is to reframe analyses of stadium and arena subsidization policies from perspectives centered upon economic and financial issues toward a perspective focused on broader issues of urban governance and the public purposes of sports facilities. Such assessments would provide a better understanding of whether such use of public resources represents good public policy.

To demonstrate this, the paper uses an integrated literature review to offer a historical analysis of sport facility development within the context of the broader assumptions that shape public policy and how sports have been used toward achieving particular public goals. This history provides a foundation for an analysis of sports facility development within the current moment as cities require team owners to invest in redevelopment activities in the neighborhoods surrounding sports facilities.

This paper asserts that focusing on the economic and financial aspects of sports facility development is a perspective that is too narrow. Instead, this paper shows that a more holistic approach, beginning with the dominant mode of urban governance and how its assumptions underlie the public purposes for which stadiums and arenas are used, provides a better explanatory framework and a deeper understanding of the issue in the contemporary moment.

Moving beyond the question of economic efficacy, the public purpose-centered approach of this paper seeks to place subsidization policies into a broader dialog with other priorities toward maximizing the public good among the broadest population.

Public service announcements (PSAs) are frequently used tools to try to change attitudes and behaviors on social issues, including texting and driving, which has been social problem for over a decade. However, the effectiveness of such PSA campaigns often meet with varying degrees of success, suggesting changes to current anti-texting and driving campaigns are needed. This study aims to examine how to design more effective anti-texting and driving PSA campaigns by identifying the elements of existing campaigns that have the strongest impact on attitude change.

In total, 682 respondents from Amazon’s Mechanical Turk participated in an online study in which they evaluated 162 real-world anti-texting and driving ads. Respondents evaluated the ads on various ad elements (i.e. type of appeal, source of emotion, discrete emotions and perceived creativity), as well as their attitudes toward the issue after seeing the ad.

PSAs that use emotional (vs rational) appeals, evoke emotion through imagery (vs text) and/or use fear (vs disgust, anger or guilt) result in the largest changes in attitude. In addition, more creative PSAs are more effective at changing attitudes.

Overall, the results provide useful information to social marketers on how to design more effective anti-texting and driving campaigns.