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Troposphere delay is one of the important error sources in global positioning system (GPS) positioning. The purpose of this paper is to analyze the accuracy and adaptability of GPS troposphere error correction models, and to provide theoretic foundation for model selection in GPS accurate positioning.

The principle of troposphere delay error effecting on GPS signals is theoretically analyzed. The model peculiarity and modeling method of the four common troposphere delay correction models: Hopfield, Saastamoinen, Black, and Egnos models are discussed detailedly. With the measurement data from Crustal Dynamics Data Information System of the technical support institution for GPS, the accuracy and applicability of the four models are quantificationally studied.

For a low elevation, Hopfield, Saastamoinen, and Black models show great agreement with each other, and have quite high precision. In the zenith direction, the maximal troposphere delay error of three models are all less than 1 dm, but Black and Hopfield models have higher precision than Saastamoinen model. Black model can be regarded as the improved form of Hopfield model: for a high elevation, precision of two models are close, while for a low elevation, Black model shows to be more effective than Hopfield model. The precision of Egnos model is quite lower than that of Black, Hopfield, and Saastamoinen models. However, Egnos model can be a better choice when it is difficult to obtain real‐time meteorological data in certain application environment.

This paper makes thorough research on GPS troposphere delay error correction models. The conclusions are presented for selecting troposphere delay models, which are useful for practical engineering application.

Temperature anomalies in the upper troposphere have become a reality as a result of global warming, which has a noticeable impact on aircraft performance. The purpose of this study is to investigate the total air temperature (TAT) anomaly observed during the cruise level and its impact on engine parameter variations.

Empirical methodology is used in this study, and it is based on measurements and observations of anomalous phenomena on the tropopause. The primary data were taken from the Boeing 747-8F's enhanced flight data recorder, which refers to the quantitative method, while the qualitative method is based on a literature review and interviews. The GEnx Integrated Vehicle Health Management system was used for the study's evaluation of engine performance to support the complete range of operational priorities throughout the entire engine lifecycle.

The study's findings indicate that TAT and SAT anomalies, which occur between 270- and 320-feet flight level, have a substantial impact on aircraft performance at cruise altitude and, as a result, on engine parameters, specifically an increase in fuel consumption and engine exhaust gas temperature values. The TAT and Ram Rise anomalies were the focus of the atmospheric deviations, which were assessed as major departures from the International Civil Aviation Organizations–defined International Standard Atmosphere, which is obvious on a positive tendency and so goes against the norms.

Necessary fixed flight parameters gathered from the aircraft's enhanced airborne flight recorder (EAFR) via Aeronautical Radio Incorporated (ARINC) 664 Part 7 at a certain velocity and altitude interfacing with the diagnostic program direct parameter display (DPD), allow for analysis of aircraft performance in a real-time frame. Thus, processed data transmits to the ground maintenance infrastructure for future evaluation and for proper maintenance solutions.

A real-time analysis of aircraft performance is possible using the diagnostic program DPD in conjunction with necessary fixed flight parameters obtained from the aircraft's EAFR via ARINC 664 Part 7 at a specific speed and altitude. Thus, processed data is transmitted to the ground infrastructure for maintenance to be evaluated in the future and to find the best maintenance fixes.

In operational tropical cyclone (TC) forecasting practice, there are usually many TC track guidances available from various official sources. When they do not converge, the guidances need to be ensembled by systematic approaches to formulate the best possible track as an official local TC track forecasting.

The main approach of the research is focused on finding an atmospheric environment favourable for TC survival (genesis) with the help of commonly accepted knowledge in atmospheric physics that reveals mechanism driving evolution and change of synoptic patterns in the atmosphere, using routinely available observational data, i.e. identification of TCF/TCR areas. The techniques developed are then applied to ensemble the TC track guidances available operationally to formulate an official TC track forecasting.

The results show that TC movement is very dependent on the atmospheric environment surrounding a TC. Whether the environment is favourable (TCF) or resistant (TCR) to survival of a TC system is a vital factor to determine where the TC moving. A systematic approach to the identification of the TCR/TCF areas is a key technique to ensemble available TC track guidances to formulate an official TC track forecasting.

In operational TC forecasting, TC track forecasting is the most important and difficult issue. The results indicate that the systematic approach to TC track forecasting has philosophical justification, solid scientific ground, sound logic and practical viability, and thus, make TC track forecasting easy and effective.

Presents results for April‐September 1996 from the Multi‐layer Atmospheric CHemistry model, Oslo (MACHO), a regional scale photo‐chemistry model, and compares to measurements. Initial and lateral boundary concentrations are provided by a global CTM (chemical tracer model). As a base run, monthly averaged concentrations for June 1996 are used as initial and lateral boundary concentrations. The sensitivity of the interior model domain to the lateral boundaries is analyzed by comparing the base run with a model run with lateral boundary concentrations updated at six‐hour intervals. In the boundary layer over Europe, differences between the two runs are small both for accumulated excesses and for concentrations on individual days, indicating that ozone levels here are determined predominantly by local European scale sources. in the free troposphere, however, the effects of the lateral boundary concentrations are shown to be significant.

IN high‐speed level flight in the compressibility region an entirely new factor makes its appearance, viz: small variations of atmospheric density and speed of sound with height. This factor affects dynamic stability due to continuous changes of height during longitudinal disturbances; there is no effect in lateral disturbances. The affects are very small in low‐speed flight but they increase steadily with Mach number. The short‐period oscillations are not affected but the corrections to phugoid motion become appreciable in high subcritical flight, larger in supercritical (transonic) range, and very important in supersonic flight. The effects of compressibility are of paramount significance but they should be considered in conjunction with varying height effects. Another result of the investigation is the appearance of a new mode of disturbance, due to the stability quartic being converted into a quintic. The fifth (real) root is often small, it may vary in sign according to aerodynamic properties of the aircraft and characteristics of the power unit. The new mode is a subsidence or a divergence, and it determines height stability or instability, hence it may show to what extent an aircraft is able to keep constant altitude over long stretches of time.

The purpose of this paper is to study the implementation of GNSS technique in aviation for recovery of aircraft’s position using Precise Point Positioning (PPP) method.

The aircraft’s coordinates in ellipsoidal frame were obtained based on GPS code and phase observations for PPP method. The numerical computations were executed in post-processing mode in the CSRS-PPP and magicPPP online services. The mathematical scheme of PPP method was development using indifference equations of Ionosphere-Free linear combination. In the experiment, airborne test using Cessna 172 aircraft on June 01, 2010 in the military airport in Deblin was realized. The aircraft’s position was determined using data from GNSS receiver (Topcon HiperPro with interval of 1 s).

In this paper, the accuracy of aircraft’s position is better than 0.07 m for CSRS-PPP service and better than 0.27 m for magicPPP service. In case of the Mean Radial Spherical Error parameter, the average value for CSRS-PPP service equals to 0.01 m, whereas for magicPPP, it is about 0.38 m. The values of vertical coordinate of Cessna 172 aircraft were also checked with results of Real Time Kinematic–On The Fly technique.

In this paper, the analysis of aircraft positioning is focused on the application of the PPP method in post-processing mode. In near real time, the PPP method still has limitations, especially in the area of ambiguity resolution and also instrumental biases (e.g. Narrow Lane Hardware Delays).

The PPP method can be applied in aviation in post-processing mode for verification of true aircraft coordinates and elimination of blunder errors from adjustment processing of GNSS observations. The Zenith Wet Delay term as a product of troposphere delay and receiver clock bias as a product of precise time transfer can be obtained in the PPP method.

The paper presents that the PPP method is an alternative solution for the recovery of aircraft’s position in aviation, and this method can be also applied in the positioning of aircraft based on GLONASS or GPS/GLONASS data.

After many years’ practice and experiments, it was found that quantitative analysis systems with unequal quantitative effect cannot be extended into that with equal quantitative effect. While it is related to such epistemological viewpoints as irregularity and continuity systems, an infrastructural form comparison has shown universally scientific and methodological characteristics. In combination with evolution of weather systems, our infrastructural analysis involves applications of super low temperatures, reversed information order, rolling currents infrastructure in reversal weather change and long‐term weather forecasting.

An earlier paper gave the background to the rôle of chlorofluorocarbons (CFCs) in the observed depletion of the Earth's stratospheric ozone, plus details of the Montreal Protocol that restricts the production and consumption of CFCs. In this paper, recent data on both the ozone depletion and the global greenhouse warming that result from CFC emissions are given. The progress by the chemical companies to identify replacements for CFCs is also discussed.

Urban tropospheric ozone (O₃) concentrations can reach 40 folds its background level due to traffic‐induced emissions and extensive industrial activities. As such, O₃ has become a pervasive air pollution problem in urban areas despite major efforts to control its precursors. In this paper, O₃ formation mechanisms are briefly described, countrywide emissions with emphasis on O₃ precursors are summarized, and field measurements of O₃ background levels and its precursors in an urban area are presented. Simulation results using a photochemical air quality model including a sensitivity analysis with respect to design ratios and mixing heights are then presented. Mitigation alternatives and policies to control O₃ formation are examined in the context of country‐specific characteristics.

The purpose of the study is focused on implementation of Global Navigation Satellite System (GLONASS) technique in civil aviation for recovery of aircraft position using Precise Point Positioning (PPP) method in kinematic mode.

The aircraft coordinates of Cessna 172 plane in XYZ geocentric frame were obtained based on GLONASS code and phase observations for PPP method. The numerical computations were executed in post-processing mode in the RTKPOST module in RTKLIB program. The mathematical scheme of equation observation of PPP method was solved using Kalman filter in stochastic processing.

In paper, the average accuracy of aircraft position is about 0.308 m for X coordinate, 0.274 m for Y coordinate, 0.379 m for Z coordinate. In case of the mean radial spherical error (MRSE) parameter, the average value equals to 0.562 m. In paper, the accuracy of aircraft position in BLh geodesic frame were also showed and described.

The PPP method can be applied for determination the coordinates of receiver, receiver clock bias, Zenith Wet Delay (ZWD) parameter and ambiguity term for each satellite.

The PPP method is a new technique for aircraft positioning in air navigation. The PPP method can be also used in receiver autonomous integrity monitoring (RAIM) module in aircraft-based augmentation system (ABAS) system in air transport. The typical accuracy for recovery the aircraft position is about cm ÷ dm level using the PPP method.

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

The work presents the original research results of implementation the GLONASS satellite technique for recovery the aircraft position in civil aviation. Currently, the presented research PPP method is used in precise positioning of aircraft in air navigation based on global positioning system and GLONASS solutions.