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The main aim of this study is to elaborately examine the error correction technology for global navigation satellite system (GNSS) navigation messages and to draw a conceptual decision support framework related to the modernization of the GNSS and other systems.

The extensive simulation model developed in Matrix Laboratory (MATLAB) is used to evaluate the performance of forward error correction (FEC) codes such as Hamming, Bose–Chaudhuri–Hocquenghem, convolutional, turbo, low-density parity check (LDPC) and polar codes under different levels of noise.

The performance and robustness of the aforementioned algorithms are compared based on the bit length, complexity and execution time of the GNSS navigation message. In terms of bit error rate, LDPC coding exhibits more ability in the robustness of the navigation message, while polar code gives better results according to the execution time.

In view of future new GNSS signals and message design, the findings of this paper may provide significant insight into navigation message modernization and design as an important part of GNSS modernization.

To the best of the authors’ knowledge, this is the first study that conducts a direct comparison of various FEC algorithms on GNSS navigation message performance against noise, taking into consideration turbo and newly developed polar codes.

The purpose of this paper is to show the performance during flight tests of the proposed GBAS Approach Service Type D navigation – intended to support autoland operations – in comparison to ILS.

An experimental GBAS station was installed at the research airport in Braunschweig. Data processing complied with the currently proposed requirements to support automatic landings. Corrections for GPS measurements and integrity parameters were sent to a research aircraft which was equipped with an experimental GPS receiver providing raw measurement data. The received data and measurements were then processed on board in real‐time and provide approach guidance information to the experimental pilot in form of a flight director indication. To evaluate system performance the authors create a truth reference track from a post processed carrier phase solution. Finally, the GBAS outputs and the received ILS signals are compared to the truth reference.

The system performed well within all specifications and showed full availability at all times during the flight. Compared to ILS, GBAS is significantly more precise and shows almost no noise.

The navigation solution was flown manually according to flight director displays, therefore no automatic approaches and landings could be performed.

It has been demonstrated that GBAS can support the intended operations under nominal conditions.

This work is part of the ongoing validation of the proposed standards for a satellite based landing system. It compares GBAS and ILS data from flight tests carried out with a representative aircraft.

Motivated by the problems that the positioning error of strap-down inertial navigation system (SINS) accumulates over time and few sensors are available for midwater navigation, this paper aims to propose a self-aided SINS scheme for the spiral-diving human-occupied vehicle (HOV) based on the characteristics of maneuvering pattern and SINS error propagation.

First, the navigation equations of SINS are simultaneously executed twice with the same inertial measurement unit (IMU) data as input to obtain two sets of SINS. Then, to deal with the horizontal velocity provided by one SINS, a delay-correction high-pass filter without phase shift and amplitude attenuation is designed. Finally, the horizontal velocity after processing is used to integrate with other SINS.

Simulation results indicate that the horizontal positioning error of the proposed scheme is less than 0.1 m when an HOV executes spiral diving to 7,000 meters under the sea and it is inherently able to estimate significant sensors biases.

The proposed scheme can provide a precise navigation solution without error growth for spiral-diving HOV on the condition that only IMU is required as a navigation sensor.

The current study aimed to develop and validate Mobile Information Security Awareness Scale (MISAS) based on the prototype model for measuring information security awareness and the relevant literature.

The scale was developed and validated with the participation of 562 students from four universities. The construct validity of the scale was tested through exploratory factor analysis and confirmatory factor analysis.

The reliability of the scale was tested through corrected item-total correlations and Cronbach alpha. The MISAS includes six factors and 17 items. The identified factors were labeled as backup, instant messaging and navigation, password protection, update, access permission and using others' devices.

The scale included only the human aspects of mobile information security. The technical aspects are not within the scope of this study. For this reason, future studies might develop and validate a different scale focusing on the technical aspects of mobile information security.

The developed scale contributes to the literature on the human aspects of mobile information security.

Describes the future air navigation system known as the Communication, Navigation and Surveillance/Air Traffic Management System, which is to be used throughout the world to organize better the increasing volume of air traffic. Details, in particular, automatic dependent surveillance, the facility used to optimize flight paths; and the Aeronautical Telecommunications Network.

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.

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 add to the knowledge about how to design websites that are stress-free, easy to navigate and relevant to children’s learning needs.

This paper involves an observational study that reports the results of website usability among sixth-grade students in a private foreign school in Kuwait. The observation pertained to search performance, usability and navigation to find the needed information using the WebPath Express database.

Most of the children navigated and searched the system without much prompting; they found the search box easily, as it was positioned at the top-centre of the page, and without keywords. Of the eight students, none used the narrow-down search option; they commonly performed searches using phrases, and consistency and simplicity aided the search process. Some gender differences were found. The boys got side-tracked easily and took a longer time to find the information they sought than the girls. User behaviour, generally, was influenced by the interface design.

Research about usability with different grade levels, with different languages and between genders needs to be conducted to provide more definitive conclusions. Sample size in observations can bring to light details that large samples cannot. The goal in observation is not statistical significance but small things that observations can bring to light.

Web designers need to take into consideration the research results in the areas of user interaction with computers and software. In designing educational tools for the young, several elements that research in general, including this one, emphasizes have to do with the location of search boxes, navigation interface and design elements, all of which can aid the learning process while providing a rewarding and fruitful educational experience.

These findings shed light on implications for cooperation between librarians and teachers and on design elements for sites tailored to school children.