Journal articles: 'Dependent surveillance system Multilateration'

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Yaro, Abdulmalik Shehu, Ahmad Zuri Sha'ameri, and Saâ€™id Musa Yarima. "Direct and Indirect TDOA Estimation based Multilateration System Position Estimation Accuracy Comparison." ELEKTRIKA- Journal of Electrical Engineering 20, no. 1 (April 30, 2021): 54–64. http://dx.doi.org/10.11113/elektrika.v20n1.226.

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Multilateration (MLAT) system estimate aircraft position from its electromagnetic emission using time difference of arrival (TDOA) estimated at ground receiving station (GRS)s with a lateration algorithm. The position estimation (PE) accuracy of the MLAT system depends on several factors one of which is the TDOA estimation approach. In this paper, the PE performance of a minimum configuration 3-dimensional (3-D) MLAT system based on the direct and indirect approaches to TDOA estimation is presented. The analysis is carried out using Monte Carlo simulation with the transmitter and receiver parameters based on an actual system used in the civil aviation. Simulation results show that within 150 km radius, the direct TDOA based MLAT system performs better than the indirect TDOA based MLAT system. Beyond 150 km radius, the indirect TDOA based MLAT system has the least PE error compared the direct TDOA based MLAT system. Further comparison of the MLAT system based on the two TDOA estimation approaches with other surveillance systems shows that the direct TDOA based MLAT system has the least PE error within 150 km radius while long-range aircraft PE beyond 150 km, automatic surveillance dependent broadcast (ADS-B) outperformed the MLAT system as it has the least PE error

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Lu, Yu, Rong Shun Huang, and Zi Li Xu. "Multi-Sensor Data Fusion Based on ADS-B and MLAT in Approach." Applied Mechanics and Materials 602-605 (August 2014): 2491–94. http://dx.doi.org/10.4028/www.scientific.net/amm.602-605.2491.

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ADS-B (Automatic Dependent Surveillance - Broadcast) and MLAT (Multilateration) are the main surveillance techniques for ATC (Air Traffic Control), and will play an important role in the future's tracking system. The fusion between ADS-B and MLAT is able to achieve more accurate tracking. In views of the data characters of these two techniques, this paper designs a concrete fusion framework with multi-levels based on federal Kalman filters to fuse ADS-B and MLAT in approach. Under this framework, both ADS-B and MLAT data are processed intensively to achieve high accuracy. Experimental results based on simulation and practical data illustrate the algorithm can achieve high precision.

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Lesturgie, Marc, Hian Lim Chan, and Sylvain Azarian. "GICS, a new concept to enhance in-flight safety and security of commercial aviation." MATEC Web of Conferences 304 (2019): 05002. http://dx.doi.org/10.1051/matecconf/201930405002.

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This paper presents a new concept of aircraft tracking based on a LEO constellation of small satellites, each of them carrying receiving and transmitting devices in order to check the integrity of the ADS-B (Automatic Dependent Surveillance - Broadcast) positioning information and proceed with a non-cooperative independent localization of the aircraft, if a flight anomaly comes out. To do so, on side of the conventional ADS-B processing, authors propose to add a multilateration process and two active radar modes, able to perform a finer and reliable localization of the aircraft, as well as a first information on the nature of the flight anomaly. The paper deals with a preliminary system analysis, although underpinned by some illustrations of existing sensor technologies, already or nearly operational in space. The concept has been patented [1].

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Mantilla-Gaviria, Ivan A., Mauro Leonardi, Gaspare Galati, Juan V. Balbastre-Tejedor, and Elías de Los Reyes Davó. "Efficient location strategy for airport surveillance using Mode-S multilateration systems." International Journal of Microwave and Wireless Technologies 4, no. 2 (February 22, 2012): 209–16. http://dx.doi.org/10.1017/s1759078712000104.

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In this paper, the use of regularization methods to solve the location problem in multilateration systems, using Mode-S signals, is studied, evaluated, and developed. The Tikhonov method has been implemented as a first application to solve the classical system of hyperbolic equations in multilateration systems. Some simulations are obtained and the results are compared with those obtained by the well-established Taylor linearization and with the Cramér–Rao lower bound analysis. Significant improvements, for the accuracy, convergence, and the probability of location, are found for the application of the Tikhonov method.

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Darabseh, Ala’, Evangelos Bitsikas, Brice Tedongmo, and Christina Pöpper. "On ADS-B Sensor Placement for Secure Wide-Area Multilateration." Proceedings 59, no. 1 (December 1, 2020): 3. http://dx.doi.org/10.3390/proceedings2020059003.

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As automatic dependent surveillance–broadcast (ADS-B) becomes more prevalent, the placement of on-ground sensors is vital for Air Traffic Control (ATC) to control the airspace. However, the current sensors are placed in an unstructured way that keeps some areas without coverage, and others are over-densified by sensors. Therefore, areas with coverage anomalies may cause issues that inhibit accurate ADS-B verifications as well as the availability of ADS-B altogether. In this paper, we tackle the ADS-B-specific optimal sensor placement (OSP) problem. Of importance are both the optimal coverage and the secure and accurate verification of received ADS-B messages. Specifically, we take into account the following objectives. First, we determine the minimum required number of sensors in order to cover a certain area like Europe. Second, we produce a better placement of the current sensors with respect to the security and accuracy of geometric dilution of precision (GDOP). Finally, we calculate how far the current sensor setup is from our derived optimal solution as well as the cost to reach the optimality. Our experiments show that the ideal fitness score for solving the OSP is below 0.1, meaning that the mean squared error (MSE) of the required and achieved GDOPs is significantly small, thus accomplishing a near-optimal setup.

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Mantilla-Gaviria, Ivan A., Mauro Leonardi, Gaspare Galati, Juan V. Balbastre-Tejedor, and Elías de los Reyes Davó. "An effective procedure to design the layout of standard and enhanced mode-S multilateration systems for airport surveillance." International Journal of Microwave and Wireless Technologies 4, no. 2 (April 2012): 199–207. http://dx.doi.org/10.1017/s1759078712000219.

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In this paper, an effective procedure to emplace standard and enhanced mode-S multilateration stations for airport surveillance is studied and developed. This procedure is based on meta-heuristic optimization techniques, such as genetic algorithm (GA), and is intended to obtain useful parameters for an optimal system configuration that provides acceptable performance levels. Furthermore, the procedure developed here is able to evaluate and improve previous system designs, as well as possible system enhancements. Additionally, the design strategies to be used along with the procedure proposed here are fully described. Parameters such as the number of stations, the system geometry, the kind of measurements to be used, and the system accuracy are obtained taking into account the basic requirements such as the Line of Sight, the probability of detection, and the accuracy levels.

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SHIOMI, Kakuichi. "A Study on Automatic Dependent Surveillance System." Journal of Japan Institute of Navigation 92 (1995): 113–21. http://dx.doi.org/10.9749/jin.92.113.

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Besada, Juan A., Gonzalo de Miguel, Ana M. Bernardos, and José R. Casar. "Automatic-dependent surveillance–broadcast experimental deployment using system wide information management." International Journal of Microwave and Wireless Technologies 4, no. 2 (April 2012): 187–98. http://dx.doi.org/10.1017/s1759078712000232.

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This paper describes an automatic-dependent surveillance–broadcast (ADS–B) implementation for air-to-air and ground-based experimental surveillance within a prototype of a fully automated air traffic management (ATM) system, under a trajectory-based-operations paradigm. The system is built using an air-inclusive implementation of system wide information management (SWIM). This work describes the relations between airborne and ground surveillance (SURGND), the prototype surveillance systems, and their algorithms. System's performance is analyzed with simulated and real data. Results show that the proposed ADS–B implementation can fulfill the most demanding surveillance accuracy requirements.

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Lande, K. "Modified Automatic Dependent Surveillance System (M-ADS) For North Sea Helicopters." Journal of Navigation 51, no. 3 (September 1998): 304–11. http://dx.doi.org/10.1017/s0373463398007887.

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The helicopter traffic over the North Sea is performed in uncontrolled airspace over international waters. The lack of radar coverage makes the establishment of controlled airspace difficult. The development of Automatic Dependent Surveillance (ADS) and use of satellite technology for Navigation, Communication and Surveillance (NCS) have made it possible to evaluate Modified Automatic Dependent Surveillance (M-ADS) as a basis for establishing controlled airspace over remote areas without radar coverage.

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Ishide, Akira, Mitsuhiro Fujita, Kenji Niimi, Fumitaka Matsuzaki, and Kiyoshi Yukawa. "Development of experimental automatic dependent surveillance system and inflight performances." Electronics and Communications in Japan (Part I: Communications) 79, no. 4 (1996): 35–45. http://dx.doi.org/10.1002/ecja.4410790404.

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Cho, Taehwan, Kanghee Kim, Jinhyuk Kim, and Sangbang Choi. "Design and Implementation of Automatic Dependent Surveillance - Broadcast Server System." Journal of Korea Navigation Institute 19, no. 3 (June 30, 2015): 182–91. http://dx.doi.org/10.12673/jant.2015.19.3.182.

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Ali, Busyairah Syd. "System specifications for developing an Automatic Dependent Surveillance-Broadcast (ADS-B) monitoring system." International Journal of Critical Infrastructure Protection 15 (December 2016): 40–46. http://dx.doi.org/10.1016/j.ijcip.2016.06.004.

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Fadil, Rabie, Badr Abou El Majd, Hassan El Ghazi, and Hicham Rahil. "Optimizing the Multi-Objective Deployment Problem of Mlat System." MATEC Web of Conferences 200 (2018): 00014. http://dx.doi.org/10.1051/matecconf/201820000014.

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Multilateration (MLAT) systems are powerful means for air traffic surveillance. These systems aim to extract, and display to air traffic controllers identification of aircrafts or vehicles equipped with a transponder. They provide an accurate and real-time data without human intervention using a number of ground receiving stations, placed in some strategic locations around the coverage area, and they are connected with a Central Processing Subsystem (CPS) to compute the target (i.e., aircraft or vehicle) position. The MLAT performance strongly depends on system layout design which consists on deploying the minimum number of stations, in order to obtain the requested system coverage and performance, meeting all the regulatory standards with a minimum cost. In general, choosing the number of stations and their locations to cope with all the requirements is not an obvious task and the system designer has to make several attempts, by trial and error, before obtaining a satisfactory spatial distribution of the stations. In this work we propose a new approach to solve the deployment of Mlat stations problem by focusing on the number of deployed stations and the coverage as the main objectives to optimize. The Non-dominated Sorting Genetic Algorithm II(NSGA-II) was used in order to minimize the total number of stations required to identify all targets in a given area, with the aim to minimize the deployment cost, accelerating processes, and achieve high availability and reliability. The proposed approach is more efficient and converge rapidly which makes it ideal for our research involving optimal deployment of Mlat station.

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Monakov, A. A., and A. M. Mirolubov. "Compensation of Positioning Errors Caused by Tropospheric Wave Propagation in Wide-Area Multilateration Systems." Journal of the Russian Universities. Radioelectronics 23, no. 6 (December 29, 2020): 59–69. http://dx.doi.org/10.32603/1993-8985-2020-23-6-59-69.

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Introduction. Wide area multilateration (WAM) systems are the main competitors of secondary surveillance radar (SSR) systems used in air traffic control (ATC). The general principle of WAM operation is based on the assessment of pseudoranges between a signal source (an aircraft airborne transponder) and the ground receivers with precisely known geographical coordinates deployed over the ATC area. The aircraft position is estimated by measuring pseudoranges. A significant factor affecting the accuracy of aircraft positioning is tropospheric refraction, a phenomenon caused by the inhomogeneity of the earth's atmosphere and manifested in a deviation in the direction of the rays along which the signal of an aircraft transponder propagates. Refraction increases the lengths of ray paths, thus increasing the corresponding pseudoranges. As a result, the estimate of the aircraft position receives an additional bias. Altitude estimates produce unreasonably large errors.Aim. To develop a mathematical model for the signals received by a WAM system, which accounts for tropospheric wave propagation, as well as to derive an algorithm for aircraft positioning with compensated tropospheric errors.Materials and methods. Equations for the pseudorange estimation errors caused by wave propagation in a spherically stratified atmosphere were derived using the method of geometrical optics.Results. This paper proposed a mathematical model for pseudorange estimates in WAM systems, which accounts for the bias associated with the phenomenon of tropospheric refraction. An analysis of the proposed model showed that pseudorange errors depend linearly on the distance between the aircraft transponder and the receiver. This conclusion allowed an algorithm for aircraft positioning with compensated tropospheric errors to be developed. The proposed algorithm yields an unbiased estimate of the aircraft position. The standard deviation of altitude estimates increases by 60%, although remaining within the limits permissible for WAM systems.Conclusions. The developed mathematical model of WAM signals, which considers tropospheric propagation errors in pseudorange estimation, as well as the algorithm for aircraft positioning with compensated tropospheric errors, can be used in the development of spatially distributed navigation systems.

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Kaplan, D. H., V. Shankaran, A. S. Dighe, E. Stockert, M. Aguet, L. J. Old, and R. D. Schreiber. "Demonstration of an interferon -dependent tumor surveillance system in immunocompetent mice." Proceedings of the National Academy of Sciences 95, no. 13 (June 23, 1998): 7556–61. http://dx.doi.org/10.1073/pnas.95.13.7556.

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Nurhayati, Yati, and Susanti Susanti. "Implementasi Automatic Dependent Surveillance Broadcast (ADS-B) di Indonesia." WARTA ARDHIA 40, no. 3 (September 30, 2014): 147–62. http://dx.doi.org/10.25104/wa.v40i3.128.147-162.

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Teknlologi ADSB is a new technology in the observation plane which is a combination of global positioning system (GPS), so that the aircraft can be traced to the position, velocity, wind direction, and altitude. This tool can be installed in the aircraft or ground stations and more superior than the radar.ADS-B is indeed a revolutionary look, start with only the antenna and the tool less than for a small refrigerator can detect aircraft and air traffic displays.Automatic Dependent Surveillance- Broadcast (ADS-B) is a detection technology where each plane passing owned transponder emits every two times per second information altitude, position, speed, direction, and other information to ground stations and other aircraft. This information is obtained from the information the Global Positioning System (GPS) or backup Flight Management System (FMS) in each plane. Teknlologi ADSB adalah teknologi baru dalam pengamatan pesawat terbang yang merupakan kombinasi global positioning system (GPS), sehingga pesawat bisa terlacak posisi, kecepatan, arah angin, dan ketinggian. Alat ini bisa dipasang di pesawat atau stasiun darat dan lebih unggul dari radar. ADS-B ini memang terlihat revolusioner, dengan hanya berbekal antenna dan alat kurang dari sebesar lemari es kecil dapat mendeteksi pesawat terbang dan menampilkan lalu lintas udara.Automatic Dependent Surveillance- Broadcast (ADS-B) adalah teknologi pendeteksi dimana setiap pesawat lewat transponder yang dimiliki memancarkan setiap dua kali dalam tiap detik informasi ketinggian, posisi, kecepatan, arah, dan informasi lainnya ke stasiun darat dan pesawat lainnya. Informasi ini didapat dari informasi Global Positioning System (GPS) atau backup Flight Management System (FMS) yang ada di pesawat masing-masing.

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Xiang, Zheng, Wei Jun Pan, and Jun Luo. "Application of Automatic Dependent Surveillance-Broadcast in the Training for Air Traffic Controller." Applied Mechanics and Materials 209-211 (October 2012): 775–78. http://dx.doi.org/10.4028/www.scientific.net/amm.209-211.775.

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The application of Automatic Dependent Surveillance-Broadcast (ADS-B) in the training for air traffic controller is investigated in the presented work. ADS-B is a surveillance technology for tracking aircraft as part of the Next Generation Air Transportation System (NextGen). Compared to radar, ADS-B system has many advantages such as lower deployment cost, higher accuracy and more frequently update. As surveillance method transits from radar surveillance to ADS-B surveillance, the training for air traffic controller should incorporate ADS-B system correspondingly. In the presented work, the features of ADS-B are introduced as well as the structure of ADS-B system is illustrated, and a novel framework for training air traffic controller with ADS-B system is proposed. It is seen that air traffic controller can be trained with lower cost, shorter period and more flexibility compared to that with radar surveillance.

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Sato, Takashi, Yasuhiro Sako, Misato Sho, Mamiko Momohara, Mary Ann Suico, Tsuyoshi Shuto, Hideki Nishitoh, et al. "STT3B-Dependent Posttranslational N-Glycosylation as a Surveillance System for Secretory Protein." Molecular Cell 47, no. 1 (July 2012): 99–110. http://dx.doi.org/10.1016/j.molcel.2012.04.015.

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Syd Ali, Busyairah, Washington Ochieng, Arnab Majumdar, Wolfgang Schuster, and Thiam Kian Chiew. "ADS-B System Failure Modes and Models." Journal of Navigation 67, no. 6 (June 17, 2014): 995–1017. http://dx.doi.org/10.1017/s037346331400037x.

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Automatic Dependent Surveillance Broadcast (ADS-B) is envisioned to support seamless aircraft surveillance and enhanced air-to-air and air-to-ground applications. ADS-B is an integrated system, dependent on on board navigation systems to obtain aircraft state information as well as a communication data link to broadcast this information to Air Traffic Control (ATC) on the ground and other ADS-B equipped aircraft. To quantify system safety, a good understanding of the potential failure modes of the system is vital. ADS-B system failure modes include those from the communication and navigation systems and human and environmental factors, as well as ADS-B-specific components. In this paper, potential failure modes of the ADS-B system are identified using an approach developed in this paper. The end output of the approach is an ADS-B failure mode register. However, the approach is transferable to other ATC surveillance systems. The paper further provides the failure classification and modelling, and also analyses the failure modes' impact on ATC operations and finally proposes potential mitigations. It is important to note that the work carried out in this paper is based on the assumption that the ADS-B operates as the primary surveillance source for the ATC.

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Ali, Busyairah Syd, Washington Yotto Ochieng, Wolfgang Schuster, Arnab Majumdar, and Thiam Kian Chiew. "A safety assessment framework for the Automatic Dependent Surveillance Broadcast (ADS-B) system." Safety Science 78 (October 2015): 91–100. http://dx.doi.org/10.1016/j.ssci.2015.04.011.

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KODO, Takahiro, Sakae NAGAOKA, Osamu AMAI, and Hideo NAKAMURA. "Models for the Along-Track Prediction Errors of an Automatic Dependent Surveillance System." Journal of Japan Institute of Navigation 110 (2004): 37–44. http://dx.doi.org/10.9749/jin.110.37.

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Subramani, Jegadeesan, Azees Maria, Ramesh Babu Neelakandan, and Arun Sekar Rajasekaran. "Efficient anonymous authentication scheme for automatic dependent surveillance‐broadcast system with batch verification." IET Communications 15, no. 9 (March 3, 2021): 1187–97. http://dx.doi.org/10.1049/cmu2.12152.

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Xu, Ya Jun. "Study on Data Fusion Algorithm of TCAS/ADS-B Integrated Surveillance System Based on the Present Statistical Model." Applied Mechanics and Materials 427-429 (September 2013): 1311–14. http://dx.doi.org/10.4028/www.scientific.net/amm.427-429.1311.

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The difference between Traffic Alert and Collision Avoidance System and Automatic Dependent Surveillance Broadcast surveillance principle was compared. A TCAS/ ADS-B integrated surveillance system based on the present statistical model was built. Using the data fusion algorithm, the optimal local track of TCAS and ADS-B ,as well as the optimal fused track of the integrated system were estimated. The simulation results show that the maximum optimal fused estimated position error is 100m, it is certificated that the integrated system can improve track estimates accuracy, improve the surveillance precision of TCAS.

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He, Debiao, Neeraj Kumar, Kim-Kwang Raymond Choo, and Wei Wu. "Efficient Hierarchical Identity-Based Signature With Batch Verification for Automatic Dependent Surveillance-Broadcast System." IEEE Transactions on Information Forensics and Security 12, no. 2 (February 2017): 454–64. http://dx.doi.org/10.1109/tifs.2016.2622682.

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Ali, Busyairah Syd, Wolfgang Schuster, and Washington Yotto Ochieng. "Evaluation of the Capability of Automatic Dependent Surveillance Broadcast to Meet the Requirements of Future Airborne Surveillance Applications." Journal of Navigation 70, no. 1 (July 14, 2016): 49–66. http://dx.doi.org/10.1017/s0373463316000412.

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Automatic Dependent Surveillance Broadcast (ADS-B) Out supports various ground applications including Air Traffic Control (ATC) surveillance in radar airspace, non-radar airspace and on the airport surface. In addition, the capability of aircraft to receive ADS-B Out messages from other aircraft within their coverage (ADS-B In) enables enhanced airborne surveillance applications. The requirements of the application vary depending on its safety-criticality. More stringent applications will require higher levels of performance. It is therefore critical that the ADS-B system performance is measured against the most stringent application it is designed for. This paper reviews the various enhanced airborne surveillance applications and the required ADS-B information to support them. It identifies the ADS-B based applications required for Air Traffic Management (ATM) modernisation under the SESAR/NextGen programs. It discusses existing ADS-B Out versions and their capabilities. A mapping exercise is undertaken to assess the credibility of the ADS-B system performance to support the functionalities and requirements of the various enhanced airborne surveillance applications and establish those that require further research and development, highlighting some of the key challenges.

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Kalintsev, Andrey S., and Evgeny A. Rubtsov. "METHOD OF DETECTING FALSE INTENTIONALLY GENERATED ADS-B SIGNALS." T-Comm 14, no. 11 (2020): 4–13. http://dx.doi.org/10.36724/2072-8735-2020-14-11-4-13.

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The International Civil Aviation Organization recommends to use advanced surveillance systems: multi-sensor surveillance system and automatic dependent surveillance broadcast. Ground stations for automatic dependent surveillance have a relatively low cost and can partially replace secondary surveillance radars in the future. Currently, the development of automatic dependent surveillance has slowed down, because the system has vulnerabilities: the complete openness of the 1090ES data link, the lack of encryption and protection against false intentionally generated signals. There are a large number of equipment on the market for receiving and processing on-board transponder signals; for specialists it's not difficult to assemble transmitting equipment that generates such signals. This poses a serious threat to information security and flight safety. The article proposes a method that allows, through a comprehensive analysis of the aircraft trajectory and the nature of the level of received signals, identify false signals generated intentionally. The proposed technique is based on identification of abnormal characteristics of false signals. To search and identify anomalous characteristics, the Mahalanobis distance is estimated. To increase the distinguishability of data and to detect intentional interference, it is necessary to modernize the antenna system of the ground station by introducing an additional antenna with a different radiation pattern. The false signal generated by the ground source is detected by a constant value of the antenna directivity ratio. The developed technique was implemented in the MATLAB software and applied to evaluate real data received from the ground-based automatic dependent surveillance station located in the Arkhangelsk air traffic management center. The power levels of the received messages of automatic dependent observation received from L-410 aircraft operating in the area of local air lines were used as reference values.

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Ali, Busyairah Syd, Washington Yotto Ochieng, and Arnab Majumdar. "ADS-B: Probabilistic Safety Assessment." Journal of Navigation 70, no. 4 (March 13, 2017): 887–906. http://dx.doi.org/10.1017/s0373463317000054.

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In the effort to quantify Automatic Dependent Surveillance Broadcast (ADS-B) system safety, the authors have identified potential ADS-B failure modes in Syd Ali et al. (2014). Based on the findings, six potential hazards of ADS-B are identified in this paper. The authors then applied the Probabilistic Safety Assessment approach which includes Fault Tree Analysis (FTA) and Importance Analysis methods to quantify the system safety. FTA is applied to measure ADS-B system availability for each identified hazard while Importance Analysis is conducted to identify the most significant failure modes that may lead to the occurrence of the hazards. In addition, risk significance and safety significance of each failure mode are also identified. The result shows that the availability for the ADS-B system as a sole surveillance means is low at 0·898 in comparison to the availability of ADS-B system as supplemental or as primary means of surveillance at 0·95 and 0·999 respectively. The latter availability values are obtained from Minimum Aviation System Performance Standards (MASPS) for Automatic Dependent Surveillance-Broadcast (DO-242A).

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Tang, Xin-min, Ji-da Chen, and Teng Li. "Unmanned aerial vehicle trajectory data fusion based on an active and passive feedback system." Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 234, no. 3 (November 26, 2019): 887–95. http://dx.doi.org/10.1177/0954410019890796.

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The surveillance data obtained from an unmanned aerial vehicle during real-time operation are very important for unmanned aerial vehicle supervision. In this study, in order to obtain more reliable and accurate unmanned aerial vehicle flight paths, we have proposed a trajectory fusion method of unmanned aerial vehicle data based on an active and passive feedback system. The active surveillance data are obtained from automatic dependent surveillance – broadcast and the passive surveillance data are derived from the unmanned aerial vehicle ground control station. The convex combination fusion algorithm is employed to fuse the two sets of data to obtain the accurate flight state and a continuous stable running track for the unmanned aerial vehicle. The simulation results showed that the fusion trajectory obtained using the convex combination fusion algorithm was smoother than the local trajectory obtained by the interacting multiple model algorithm.

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Carrithers, Michael D., Irene Visintin, Christophe Viret, and Charles A. Janeway. "Role of genetic background in P selectin-dependent immune surveillance of the central nervous system." Journal of Neuroimmunology 129, no. 1-2 (August 2002): 51–57. http://dx.doi.org/10.1016/s0165-5728(02)00172-8.

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Zhao, Peng, and Yongming Liu. "Separation Risk Evaluation Considering Positioning Uncertainties from the Automatic Dependent Surveillance-Broadcast (ADS-B) System." Journal of Navigation 72, no. 5 (May 2, 2019): 1179–99. http://dx.doi.org/10.1017/s0373463319000195.

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A probabilistic methodology for separation loss probability assessments is proposed in this paper. The key focus is on the effect of uncertainties from multiple Automatic Dependent Surveillance-Broadcast (ADS-B) systems on the separation loss probability assessment. First, a brief review of the ADS-B system and its associated uncertainty quantification metrics is discussed. It is found that most existing studies focus on the individual ADS-B uncertainty quantification for a single aircraft, which is not sufficient for separation loss probability assessment when two or more aircraft are involved. Next, a probabilistic positioning model with multiple aircraft is proposed and various types of uncertainties are included in the proposed model. Numerical simulations show that a navigation satellite fault can significantly affect separation error when individual aircraft see different satellite sets. Following this, several demonstration examples are illustrated to show the bounds for separation loss probability estimation. Finally, several conclusions and suggestions are discussed based on this study. One major finding is that the separation risk significantly increases when two nearby aircraft use different satellite sets to navigate. Real-time assessment of this risk should be performed.

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Wang, Jian Hui. "Applied Technology in Data Evaluation and Position Quality of ADS-B System." Advanced Materials Research 1022 (August 2014): 333–36. http://dx.doi.org/10.4028/www.scientific.net/amr.1022.333.

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Automatic dependent surveillance-broadcast (ADS-B) is a totally new surveillance method, so before practically applied and operated in China, abundant tests and evaluations are necessary to validate the performance of ADS-B and guarantee the operational security. To solve the asynchronous problem among radar data, ADS-B data and real-time kinematic (RTK) data caused by different update rates, this paper proposes the technique of synchronizing multi-surveillance data by extrapolating from the data of low update rate to high update rate according to velocity and heading. Meanwhile, because radar data, ADS-B data and RTK data are expressed in different coordinates and cannot be compared each other, this article provides a method to unifying the coordinates of multi-surveillance data. By the analysis and evaluation, we can conclude that the performance of ADS-B is better than radar. Addtionally, the paper makes focus study on the position quality indicator and the encoding rules, and puts forward the conversion between the different rules. The paper provides the technical guide for the manufacturers and the airlines.

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Chen, Shiwen, Junjian Yuan, Xiaopeng Xing, and Xin Qin. "Research on emitter individual identification technology based on Automatic Dependent Surveillance–Broadcast signal." International Journal of Distributed Sensor Networks 17, no. 2 (February 2021): 155014772199262. http://dx.doi.org/10.1177/1550147721992626.

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Aiming at the shortcomings of the research on individual identification technology of emitters, which is primarily based on theoretical simulation and lack of verification equipment to conduct external field measurements, an emitter individual identification system based on Automatic Dependent Surveillance–Broadcast is designed. On one hand, the system completes the individual feature extraction of the signal preamble. On the other hand, it realizes decoding of the transmitter’s individual identity information and generates an individual recognition training data set, on which we can train the recognition network to achieve individual signal recognition. For the collected signals, six parameters were extracted as individual features. To reduce the feature dimensions, a Bessel curve fitting method is used for four of the features. The spatial distribution of the Bezier curve control points after fitting is taken as an individual feature. The processed features are classified with multiple classifiers, and the classification results are fused using the improved Dempster–Shafer evidence theory. Field measurements show that the average individual recognition accuracy of the system reaches 88.3%, which essentially meets the requirements.

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Mao, Yi, Yi Yang, and Yuxin Hu. "Research into a Multi-Variate Surveillance Data Fusion Processing Algorithm." Sensors 19, no. 22 (November 15, 2019): 4975. http://dx.doi.org/10.3390/s19224975.

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Targeted information sources include radar and ADS (Automatic Dependent Surveillance) for civil ATM (Air Traffic Management) systems, and the new navigation system based on satellites has the capability of global coverage. In order to solve the surveillance problem in mid-and-high altitude airspace and approaching airspace, this paper proposes a filter-based covariance matrix weighting method, measurement variance weighting method, and measurement-first weighted fusion method weighting integration algorithm to improve the efficiency of data integration calculation under fixed accuracy. Besides this, this paper focuses on the technology of the integration of a multi-radar surveillance system and automated related surveillance system in the ATM system and analyzes the constructional method of a multigeneration surveillance data integration system, as well as establishing the targeted model of sensors and the target track and designing the logical structure of multi-radar and ADS data integration.

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Stojce Ilcev, Dimov. "Implementation of innovative aeronautical communication, navigation and surveillance (CNS) systems." International Journal of Engineering & Technology 8, no. 4 (November 17, 2019): 572. http://dx.doi.org/10.14419/ijet.v8i4.30014.

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This paper introduces implementation of innovative Satellite Communication, Navigation and Surveillance (CNS) systems in function of Global Satellite Augmentation System (GSAS) integrated by the current and new projected Regional Satellite Augmentation System (RSAS) worldwide. The satellite communication and navigation systems are presently in use, however the main aspect of any hypothetical RSAS network is implementation of satellite surveillance system employing previous and new CNS solutions for improved Air Traffic Control (ATC) and Air Traffic Management (ATM) in all phases of flight, approaching to airports and during landing. The CNS network also enhances safety and emergency systems, transport security and control of transportation freight, logistics and the security of the crew and passengers onboard aircraft. The proposals for modern multifunctional space segment, DVB-RCS network, RSAS infrastructure, Satellite Automatic Dependent Surveillance-Broadcast SADS-B system for surveillance and movement guidance and control are also discussed as special solutions in airports environments.

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Barson, John V. "Automatic Dependent Surveillance-Broadcast (ADS-B)–The First Step in the FAA's Next-Generation Air Transportation System." Aviation, Space, and Environmental Medicine 80, no. 4 (April 1, 2009): 422–23. http://dx.doi.org/10.3357/asem.21002.2009.

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Riahi Manesh, Mohsen, and Naima Kaabouch. "Analysis of vulnerabilities, attacks, countermeasures and overall risk of the Automatic Dependent Surveillance-Broadcast (ADS-B) system." International Journal of Critical Infrastructure Protection 19 (December 2017): 16–31. http://dx.doi.org/10.1016/j.ijcip.2017.10.002.

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Kong, Wei, Shutang Tan, Qing Zhao, De-Li Lin, Zhi-Hong Xu, Jiří Friml, and Hong-Wei Xue. "mRNA surveillance complex PELOTA–HBS1 regulates phosphoinositide-dependent protein kinase1 and plant growth." Plant Physiology 186, no. 4 (April 30, 2021): 2003–20. http://dx.doi.org/10.1093/plphys/kiab199.

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Abstract The quality control system for messenger RNA (mRNA) is fundamental for cellular activities in eukaryotes. To elucidate the molecular mechanism of 3′-phosphoinositide-dependent protein kinase1 (PDK1), a master regulator that is essential throughout eukaryotic growth and development, we employed a forward genetic approach to screen for suppressors of the loss-of-function T-DNA insertion double mutant pdk1.1 pdk1.2 in Arabidopsis thaliana. Notably, the severe growth attenuation of pdk1.1 pdk1.2 was rescued by sop21 (suppressor of pdk1.1 pdk1.2), which harbors a loss-of-function mutation in PELOTA1 (PEL1). PEL1 is a homolog of mammalian PELOTA and yeast (Saccharomyces cerevisiae) DOM34p, which each form a heterodimeric complex with the GTPase HBS1 (HSP70 SUBFAMILY B SUPPRESSOR1, also called SUPERKILLER PROTEIN7, SKI7), a protein that is responsible for ribosomal rescue and thereby assures the quality and fidelity of mRNA molecules during translation. Genetic analysis further revealed that a dysfunctional PEL1–HBS1 complex failed to degrade the T-DNA-disrupted PDK1 transcripts, which were truncated but functional, and thus rescued the growth and developmental defects of pdk1.1 pdk1.2. Our studies demonstrated the functionality of a homologous PELOTA–HBS1 complex and identified its essential regulatory role in plants, providing insights into the mechanism of mRNA quality control.

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Guo, Jianming, Lei Yang, Quan Chen, Sunquan Yu, Xiaoqian Chen, and Yong Zhao. "Design of a Low Earth Orbit Satellite Constellation Network for Air Traffic Surveillance." Journal of Navigation 73, no. 6 (May 20, 2020): 1263–83. http://dx.doi.org/10.1017/s0373463320000260.

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The satellite constellation with automatic dependent surveillance-broadcast on-board is of great importance for air traffic surveillance due to its multiple advantages compared with traditional methods. Although some research has been conducted on satellite constellation design based on coverage performance, the findings cannot entirely satisfy all the requirements of air traffic surveillance owing to the lack of analysis on inter-satellite links and network transmission. This paper presents a novel design of a low earth orbit satellite constellation network to solve this problem. Based on the requirements of space-based surveillance, an evaluation model of constellation performance is proposed concerning coverage, link and transmission. The simulation results show that the evaluation model can reflect the performance of a satellite constellation network designed for a space-based surveillance system, and a 55-satellite constellation design scheme with fairly good performance can fulfil the function of global real-time air traffic surveillance.

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Roy, Palash, and Debasis Dawn. "High‐power and high‐efficiency complementary metal–oxide–semiconductor voltage‐controlled oscillator for automatic dependent surveillance‐broadcast system." IET Microwaves, Antennas & Propagation 9, no. 14 (November 2015): 1632–37. http://dx.doi.org/10.1049/iet-map.2014.0803.

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Faieza, Aziz Abdul, S. N. Rashid, and N. Zulkifli. "Communication System Improvement for Air Traffic Service to Provide a Continuous Surveillance over the Oceanic Area." Applied Mechanics and Materials 564 (June 2014): 604–7. http://dx.doi.org/10.4028/www.scientific.net/amm.564.604.

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Air traffic service is an extra-ventricular service which regulates and assists aircraft in real time to ensure their safe operations. The importance of the air traffic service is to prevent collision between aircraft and to expedite and maintain an orderly flow of the air traffic. The objective of this project is to assess the effectiveness of the installed system in assisting the air traffic controller in providing the air traffic service. In order to achieve this objective, the Automatic Dependent Surveillance and Controller Pilot Data Link Communication (ADS/CPDLC) system has been installed and its functionality to provide continuous surveillance and communication has been evaluated. A survey of 35 air traffic controllers had participated to assess the effectiveness of the system to the air traffic controller. The results showed that over 80% of the air traffic controllers agree that the system is able to provide a continuous surveillance and continuous communication over the oceanic area. Apart from that, 60% of the air traffic controllers agree the reduced separation minima can be applies over the oceanic area by using the application of the system. Base on this result, reduced separation minima over the oceanic area can be applied in order to expedite and maintain an orderly flow of air traffic over the oceanic area.

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Lin, Ying-Hong, Chin E. Lin, and Hsu-Chan Chen. "ADS-B Like UTM Surveillance Using APRS Infrastructure." Aerospace 7, no. 7 (July 21, 2020): 100. http://dx.doi.org/10.3390/aerospace7070100.

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Automatic packet reporting system (APRS) is selected as a candidate for automatic dependent surveillance-broadcast (ADS-B) like solution for unmanned aircraft system traffic management (UTM). The APRS on-board unit (OBU) at 0.5 W radio power and a proper ground transceiver station (GTS) deployment together makes up the infrastructure for unmanned aerial vehicle (UAV) surveillance. The airborne APRS OBU, designed and built using an available LightAPRS module, and the GTS to relay received data into the UTM Cloud is developed in this study. By system integration, the APRS OBU reports position data and flight data periodically to UTM Cloud. This paper presents the development of the ADS-B like operation for UTM using APRS. To avoid communication jamming by HAMs, the adopted APRS shifts its carrying frequency from 144.64 MHz to 144.61 MHz. In addition, the data period is tuned to around 10 s to test its functional capability. The APRS OBU downlinks 90 bytes of surveillance data onto the UTM cloud using the Internet, including position and flight data from Pixhawk flight controller (FC). A series of system performance verifications are conducted to examine APRS ADS-B like reliability and continuity with coverage limit. Through 19 flight tests, the GTS collected 1330 packets of data out of 1331 transmitted from the APRS OBU. Each data packet has the complete 90 bytes for surveillance with position and six degree-of-freedom (DoF) flight data on the UTM cloud. The APRS GTS deployment, with a low rate of missing data, covers a 40 km radius at the specific frequency of 144.61 MHz. The test results verify the functional capability of APRS to support an ADS-B like for UTM in Taiwan.

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Leonardi, Mauro, and Gheorghe Sirbu. "ADS-B Crowd-Sensor Network and Two-Step Kalman Filter for GNSS and ADS-B Cyber-Attack Detection." Sensors 21, no. 15 (July 22, 2021): 4992. http://dx.doi.org/10.3390/s21154992.

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Automatic Dependent Surveillance-Broadcast is an Air Traffic Control system in which aircraft transmit their own information (identity, position, velocity, etc.) to ground sensors for surveillance purposes. This system has many advantages compared to the classical surveillance radars: easy and low-cost implementation, high accuracy of data, and low renewal time, but also limitations: dependency on the Global Navigation Satellite System, a simple unencrypted and unauthenticated protocol. For these reasons, the system is exposed to attacks like jamming/spoofing of the on-board GNSS receiver or false ADS-B messages’ injection. After a mathematical model derivation of different types of attacks, we propose the use of a crowd sensor network capable of estimating the Time Difference Of Arrival of the ADS-B messages together with a two-step Kalman filter to detect these attacks (on-board GNSS/ADS-B tampering, false ADS-B message injection, GNSS Spoofing/Jamming). Tests with real data and simulations showed that the algorithm can detect all these attacks with a very high probability of detection and low probability of false alarm.

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Grossman, Nina T., Cau D. Pham, Angela A. Cleveland, and Shawn R. Lockhart. "Molecular Mechanisms of Fluconazole Resistance in Candida parapsilosis Isolates from a U.S. Surveillance System." Antimicrobial Agents and Chemotherapy 59, no. 2 (December 1, 2014): 1030–37. http://dx.doi.org/10.1128/aac.04613-14.

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ABSTRACTCandida parapsilosisis the second or third most common cause of candidemia in many countries. The Infectious Diseases Society of America recommends fluconazole as the primary therapy forC. parapsilosiscandidemia. Although the rate of fluconazole resistance amongC. parapsilosisisolates is low in most U.S. institutions, the resistance rate can be as high as 7.5%. This study was designed to assess the mechanisms of fluconazole resistance in 706 incident bloodstream isolates from U.S. hospitals. We sequenced theERG11andMRR1genes of 122C. parapsilosisisolates with resistant (30 isolates; 4.2%), susceptible dose-dependent (37 isolates; 5.2%), and susceptible (55 isolates) fluconazole MIC values and used real-time PCR of RNA from 17 isolates to investigate the regulation ofMDR1. By comparing these isolates to fully fluconazole-susceptible isolates, we detected at least two mechanisms of fluconazole resistance: an amino acid substitution in the 14-α-demethylase geneERG11and overexpression of the efflux pumpMDR1, possibly due to point mutations in theMRR1transcription factor that regulatesMDR1. TheERG11single nucleotide polymorphism (SNP) was found in 57% of the fluconazole-resistant isolates and in no susceptible isolates. TheMRR1SNPs were more difficult to characterize, as not all resulted in overexpression ofMDR1and not allMDR1overexpression was associated with an SNP inMRR1. Further work to characterize theMRR1SNPs and search for overexpression of other efflux pumps is needed.

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Ali, Busyairah Syd, and Nur Asheila Taib. "A Study on Geometric and Barometric Altitude Data in Automatic Dependent Surveillance Broadcast (ADS-B) Messages." Journal of Navigation 72, no. 5 (May 8, 2019): 1140–58. http://dx.doi.org/10.1017/s0373463319000201.

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In Air Traffic Control (ATC), aircraft altitude data is used to keep an aircraft within a specified minimum distance vertically from other aircraft, terrain and obstacles to reduce the risk of collision. Two types of altitude data are downlinked by radar; actual flight level (Mode C) and selected altitude (Mode S). Flight level indicates pressure altitude, also known as barometric altitude used by controllers for aircraft vertical separation. ‘Selected altitude’ presents intent only, and hence cannot be used for separation purposes. The emergence of Global Navigation Satellite Systems (GNSSs) has enabled geometric altitude on board and to the controllers via the Automatic Dependent Surveillance-Broadcast (ADS-B) system. In addition, ADS-B provides quality indicator parameters for both geometric and barometric altitudes. Availability of this information will enhance Air Traffic Management (ATM) safety. For example, incidents due to Altimetry System Error (ASE) may potentially be avoided with this information. This work investigates the use and availability of these parameters and studies the characteristics of geometric and barometric data and other data that complement the use of these altitude data in the ADS-B messages. Findings show that only 8·7% of the altitude deviation is < 245 feet (which is a requirement of the International Civil Aviation Organization (ICAO) to operate in Reduced Vertical Separation Minimum (RVSM) airspace). This work provides an alert/guidance for future ground or airborne applications that may utilise geometric/barometric altitude data from ADS-B, to include safety barriers that can be found or analysed from the ADS-B messages itself to ensure ATM safety.

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van den Hurk, Andrew F., Sonja Hall-Mendelin, Cheryl A. Johansen, David Warrilow, and Scott A. Ritchie. "Evolution of Mosquito-Based Arbovirus Surveillance Systems in Australia." Journal of Biomedicine and Biotechnology 2012 (2012): 1–8. http://dx.doi.org/10.1155/2012/325659.

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Control of arboviral disease is dependent on the sensitive and timely detection of elevated virus activity or the identification of emergent or exotic viruses. The emergence of Japanese encephalitis virus (JEV) in northern Australia revealed numerous problems with performing arbovirus surveillance in remote locations. A sentinel pig programme detected JEV activity, although there were a number of financial, logistical, diagnostic and ethical limitations. A system was developed which detected viral RNA in mosquitoes collected by solar or propane powered CO2-baited traps. However, this method was hampered by trap-component malfunction, microbial contamination and large mosquito numbers which overwhelmed diagnostic capabilities. A novel approach involves allowing mosquitoes within a box trap to probe a sugar-baited nucleic-acid preservation card that is processed for expectorated arboviruses. In a longitudinal field trial, both Ross River and Barmah Forest viruses were detected numerous times from multiple traps over different weeks. Further refinements, including the development of unpowered traps and use of yeast-generated CO2, could enhance the applicability of this system to remote locations. New diagnostic technology, such as next generation sequencing and biosensors, will increase the capacity for recognizing emergent or exotic viruses, while cloud computing platforms will facilitate rapid dissemination of data.

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Nishimoto, Rei, Sandra Derouiche, Kei Eto, Aykut Deveci, Makiko Kashio, Yoshitaka Kimori, Yoshikazu Matsuoka, Hiroshi Morimatsu, Junichi Nabekura, and Makoto Tominaga. "Thermosensitive TRPV4 channels mediate temperature-dependent microglia movement." Proceedings of the National Academy of Sciences 118, no. 17 (April 22, 2021): e2012894118. http://dx.doi.org/10.1073/pnas.2012894118.

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Microglia maintain central nervous system homeostasis by monitoring changes in their environment (resting state) and by taking protective actions to equilibrate such changes (activated state). These surveillance and protective roles both require constant movement of microglia. Interestingly, induced hypothermia can reduce microglia migration caused by ischemia, suggesting that microglia movement can be modulated by temperature. Although several ion channels and transporters are known to support microglia movement, the precise molecular mechanism that regulates temperature-dependent movement of microglia remains unclear. Some members of the transient receptor potential (TRP) channel superfamily exhibit thermosensitivity and thus are strong candidates for mediation of this phenomenon. Here, we demonstrate that mouse microglia exhibit temperature-dependent movement in vitro and in vivo that is mediated by TRPV4 channels within the physiological range of body temperature. Our findings may provide a basis for future research into the potential clinical application of temperature regulation to preserve cell function via manipulation of ion channel activity.

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Van Der Pryt, Richard, and Ron Vincent. "A Simulation of the Reception of Automatic Dependent Surveillance-Broadcast Signals in Low Earth Orbit." International Journal of Navigation and Observation 2015 (August 23, 2015): 1–11. http://dx.doi.org/10.1155/2015/567604.

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Automatic Dependent Surveillance-Broadcast (ADS-B) is an air traffic surveillance technology in which aircraft transmit position and identification. The development of space-based ADS-B will allow precise control of aircraft in areas that are not covered by radar, such as oceanic regions and high latitudes. The Royal Military College of Canada has developed a spaceborne ADS-B receiver scheduled to fly on the Canadian Advanced Nanospace eXperiment-7 (CanX-7) satellite. The payload is planned to collect data over the North Atlantic region, which will then be compared to truth data provided by air traffic services. A model was created to determine power levels arriving at the satellite to provide confidence in the ADS-B receiver and antenna proposed for CanX-7. The model takes into account neutral atmosphere and ionospheric effects, aircraft-satellite geometry, and antenna radiation patterns. A simulation was run by inserting real aircraft data from the North Atlantic Track System into the model and placing the satellite at altitudes of 400, 600, and 800 km. Results of the simulation indicate that power received at the satellite, ranging between −98.5 dBm and −103 dBm for the selected altitudes, will be sufficient to successfully conduct the mission.

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Leonardi, Mauro, and Fabrizio Gerardi. "Aircraft Mode S Transponder Fingerprinting for Intrusion Detection." Aerospace 7, no. 3 (March 18, 2020): 30. http://dx.doi.org/10.3390/aerospace7030030.

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Nowadays, aircraft safety is based on different systems and four of them share the same data-link protocol: Secondary Surveillance Radar, Automatic Dependent Surveillance System, Traffic Collision Avoidance System, and Traffic Information System use the Mode S protocol to send and receive information. This protocol does not provide any kind of authentication, making some of these applications vulnerable to cyberattacks. In this paper, an intrusion detection mechanism based on transmitter Radio Frequency (RF) fingerprinting is proposed to distinguish between legitimate messages and fake ones. The proposed transmitter signature is described and an intrusion detection algorithm is developed and evaluated in case of different intrusion configurations, also with the use of real recorded data. The results show that it is possible to detect the presence of fake messages with a high probability of detection and very low probability of false alarm.

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Degeling, Chris, Gang Chen, Gwendolyn L. Gilbert, Victoria Brookes, Thi Thai, Andrew Wilson, and Jane Johnson. "Changes in public preferences for technologically enhanced surveillance following the COVID-19 pandemic: a discrete choice experiment." BMJ Open 10, no. 11 (November 2020): e041592. http://dx.doi.org/10.1136/bmjopen-2020-041592.

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ObjectivesAs governments attempt to navigate a path out of COVID-19 restrictions, robust evidence is essential to inform requirements for public acceptance of technologically enhanced communicable disease surveillance systems. We examined the value of core surveillance system attributes to the Australian public, before and during the early stages of the current pandemic.DesignA discrete choice experiment was conducted in Australia with a representative group of respondents, before and after the WHO declared COVID-19 a Public Health Emergency of International Concern. We identified and investigated the relative importance of seven attributes associated with technologically enhanced disease surveillance: respect for personal autonomy; privacy/confidentiality; data certainty/confidence; data security; infectious disease mortality prevention; infectious disease morbidity prevention; and attribution of (causal) responsibility. Specifically, we explored how the onset of the COVID-19 outbreak influenced participant responses.Setting and participants2008 Australians (general public) completed the experiment: 793 before COVID-19 outbreak onset (mean age 45.9 years, 50.2% male) and 1215 after onset (mean age 47.2 years, 49% male).ResultsAll seven attributes significantly influenced respondents’ preferences for communicable disease surveillance systems. After onset, participants demonstrated greater preference for a surveillance system that could prevent a higher number of illnesses and deaths, and were less concerned about their personal autonomy. However, they also increased their preference for a system with high data security.ConclusionsPublic acceptance of technology-based communicable disease surveillance is situation dependent. During an epidemic, there is likely to be greater tolerance of technologically enhanced disease surveillance systems that result in restrictions on personal activity if such systems can prevent high morbidity and mortality. However, this acceptance of lower personal autonomy comes with an increased requirement to ensure data security. These findings merit further research as the pandemic unfolds and strategies are put in place that enable individuals and societies to live with SARS-CoV-2 endemicity.

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Karki, Saugat, Adam Weiss, Jina Dcruz, Dorothy Hunt, Brandon Haigood, Philip Tchindebet Ouakou, Elisabeth Chop, et al. "Assessment of the Chad guinea worm surveillance information system: A pivotal foundation for eradication." PLOS Neglected Tropical Diseases 15, no. 8 (August 9, 2021): e0009675. http://dx.doi.org/10.1371/journal.pntd.0009675.

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Background In the absence of a vaccine or pharmacological treatment, prevention and control of Guinea worm disease is dependent on timely identification and containment of cases to interrupt transmission. The Chad Guinea Worm Eradication Program (CGWEP) surveillance system detects and monitors Guinea worm disease in both humans and animals. Although Guinea worm cases in humans has declined, the discovery of canine infections in dogs in Chad has posed a significant challenge to eradication efforts. A foundational information system that supports the surveillance activities with modern data management practices is needed to support continued program efficacy. Methods We sought to assess the current CGWEP surveillance and information system to identify gaps and redundancies and propose system improvements. We reviewed documentation, consulted with subject matter experts and stakeholders, inventoried datasets to map data elements and information flow, and mapped data management processes. We used the Information Value Cycle (IVC) and Data-Information System-Context (DISC) frameworks to help understand the information generated and identify gaps. Results Findings from this study identified areas for improvement, including the need for consolidation of forms that capture the same demographic variables, which could be accomplished with an electronic data capture system. Further, the mental models (conceptual frameworks) IVC and DISC highlighted the need for more detailed, standardized workflows specifically related to information management. Conclusions Based on these findings, we proposed a four-phased roadmap for centralizing data systems and transitioning to an electronic data capture system. These included: development of a data governance plan, transition to electronic data entry and centralized data storage, transition to a relational database, and cloud-based integration. The method and outcome of this assessment could be used by other neglected tropical disease programs looking to transition to modern electronic data capture systems.

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Journal articles on the topic 'Dependent surveillance system Multilateration'

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