scholarly journals Wasserstein Metric-Based Location Spoofing Attack Detection in WiFi Positioning Systems

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Yinghua Tian ◽  
Nae Zheng ◽  
Xiang Chen ◽  
Liuyang Gao
Keyword(s):  
Urban Areas ◽  
Experimental Tests ◽  
Attack Detection ◽  
Wasserstein Metric ◽  
Detection Scheme ◽  
Location Services ◽  
Positioning Systems ◽  
Distribution Features ◽  
Set Up ◽  
Location Spoofing

WiFi positioning systems (WPS) have been introduced as parts of 5G location services (LCS) to provide fast positioning results of user devices in urban areas. However, they are prominently threatened by location spoofing attacks. To end this, we present a Wasserstein metric-based attack detection scheme to counter the location spoofing attacks in the WPS. The Wasserstein metric is used to measure the similarity of each two hotspots by their signal’s frequency offset distribution features. Then, we apply the clustering method to find the fake hotspots which are generated by the same device. When applied with WPS, the proposed method can prevent location spoofing by filtering out the fake hotspots set by attackers. We set up experimental tests by commercial WiFi devices, which show that our method can detect fake devices with 99% accuracy. Finally, the real-world test shows our method can effectively secure the positioning results against location spoofing attacks.

scholarly journals Evaluation of Multi-Sensor Fusion Methods for Ultrasonic Indoor Positioning

2021 ◽  
Vol 11 (15) ◽  
pp. 6805
Author(s):  
Khaoula Mannay ◽  
Jesús Ureña ◽  
Álvaro Hernández ◽  
José M. Villadangos ◽  
Mohsen Machhout ◽  
...  
Keyword(s):  
Kalman Filter ◽  
Experimental Tests ◽  
Indoor Positioning ◽  
Location Based Services ◽  
Smart Devices ◽  
Final Position ◽  
Positioning Systems ◽  
Local Positioning System ◽  
Tightly Coupled ◽  
Position Estimate

Indoor positioning systems have become a feasible solution for the current development of multiple location-based services and applications. They often consist of deploying a certain set of beacons in the environment to create a coverage volume, wherein some receivers, such as robots, drones or smart devices, can move while estimating their own position. Their final accuracy and performance mainly depend on several factors: the workspace size and its nature, the technologies involved (Wi-Fi, ultrasound, light, RF), etc. This work evaluates a 3D ultrasonic local positioning system (3D-ULPS) based on three independent ULPSs installed at specific positions to cover almost all the workspace and position mobile ultrasonic receivers in the environment. Because the proposal deals with numerous ultrasonic emitters, it is possible to determine different time differences of arrival (TDOA) between them and the receiver. In that context, the selection of a suitable fusion method to merge all this information into a final position estimate is a key aspect of the proposal. A linear Kalman filter (LKF) and an adaptive Kalman filter (AKF) are proposed in that regard for a loosely coupled approach, where the positions obtained from each ULPS are merged together. On the other hand, as a tightly coupled method, an extended Kalman filter (EKF) is also applied to merge the raw measurements from all the ULPSs into a final position estimate. Simulations and experimental tests were carried out and validated both approaches, thus providing average errors in the centimetre range for the EKF version, in contrast to errors up to the meter range from the independent (not merged) ULPSs.

scholarly journals Concept for controlled adjustment of residual stress states in semi-finished products by gradation extrusion

2021 ◽  
Author(s):  
René Selbmann ◽  
Markus Baumann ◽  
Mateus Dobecki ◽  
Markus Bergmann ◽  
Verena Kräusel ◽  
...  
Keyword(s):  
Residual Stress ◽  
Stress Distribution ◽  
Experimental Tests ◽  
Residual Stress Distribution ◽  
Forming Process ◽  
Compressive Stresses ◽  
Energy Consuming ◽  
Stress States ◽  
Set Up ◽  
Time And Energy

AbstractThe residual stress distribution in extruded components and wires after a conventional forming process is frequently unfavourable for subsequent processes, such as bending operations. High tensile residual stresses typically occur near the surface of the wire and thus limit further processability of the material. Additional heat treatment operations or shot peening are often inserted to influence the residual stress distribution in the material after conventional manufacturing. This is time and energy consuming. The research presented in this paper contains an approach to influence the residual stress distribution by modifying the forming process for wire-like applications. The aim of this process is to lower the resulting tensile stress levels near the surface or even to generate compressive stresses. To achieve these residual compressive stresses, special forming elements are integrated in the dies. These modifications in the forming zone have a significant influence on process properties, such as degree of deformation and deformation direction, but typically have no influence on the diameter of the product geometry. In the present paper, the theoretical approach is described, as well as the model set-up, the FE-simulation and the results of the experimental tests. The characterization of the residual stress states in the specimen was carried out by X-ray diffraction using the sin2Ψ method.

scholarly journals A cooperative DDoS attack detection scheme based on entropy and ensemble learning in SDN

2021 ◽  
Vol 2021 (1) ◽  
Author(s):  
Shanshan Yu ◽  
Jicheng Zhang ◽  
Ju Liu ◽  
Xiaoqing Zhang ◽  
Yafeng Li ◽  
...  
Keyword(s):  
Ensemble Learning ◽  
Denial Of Service ◽  
Attack Detection ◽  
Coarse Grained ◽  
Communication Overhead ◽  
Detection Scheme ◽  
Fine Grained ◽  
Ddos Attack ◽  
Network Status ◽  
Ddos Attack Detection

AbstractIn order to solve the problem of distributed denial of service (DDoS) attack detection in software-defined network, we proposed a cooperative DDoS attack detection scheme based on entropy and ensemble learning. This method sets up a coarse-grained preliminary detection module based on entropy in the edge switch to monitor the network status in real time and report to the controller if any abnormality is found. Simultaneously, a fine-grained precise attack detection module is designed in the controller, and a ensemble learning-based algorithm is utilized to further identify abnormal traffic accurately. In this framework, the idle computing capability of edge switches is fully utilized with the design idea of edge computing to offload part of the detection task from the control plane to the data plane innovatively. Simulation results of two common DDoS attack methods, ICMP and SYN, show that the system can effectively detect DDoS attacks and greatly reduce the southbound communication overhead and the burden of the controller as well as the detection delay of the attacks.

scholarly journals GPS Signal Detection under Multiplicative and Additive Noise

2012 ◽  
Vol 66 (4) ◽  
pp. 479-500 ◽  
Author(s):  
P. Huang ◽  
Y. Pi ◽  
I. Progri
Keyword(s):  
Signal Detection ◽  
Urban Areas ◽  
Multiplicative Noise ◽  
Additive Noise ◽  
Power Level ◽  
Signal Propagation ◽  
Signal Acquisition ◽  
Detection Scheme ◽  
Additive And Multiplicative Noise ◽  
Gps Signal Acquisition

In some Global Positioning System (GPS) signal propagation environments, especially in the ionosphere and urban areas with heavy multipath, GPS signal encounters not only additive noise but also multiplicative noise. In this paper we compare and contrast the conventional GPS signal acquisition method which focuses on handling GPS signal acquisition with additive noise, with the enhanced GPS signal processing under multiplicative noise by proposing an extension of the GPS detection mechanism, to include the GPS detection model that explains detection of the GPS signal under additive and multiplicative noise. For this purpose, a novel GPS signal detection scheme based on high order cyclostationarity is proposed. The principle is introduced, the GPS signal detection structure is described, the ambiguity of initial PseudoRandom Noise (PRN) code phase and Doppler shift of GPS signal is analysed. From the simulation results, the received GPS signal at low power level, which is degraded by additive and multiplicative noise, can be detected under the condition that the received block of GPS data length is at least 1·6 ms and sampling frequency is at least 5 MHz.

scholarly journals A Narrative Review of Libidibia ferrea: Botanical Aspects, Ethnopharmacological Properties, Phytochemical Characteristics, Toxicity, and Experimental Tests

2021 ◽  
pp. 16-30
Author(s):  
Nayanne C. O. da S. Almeida ◽  
Silvania da C. Furtado ◽  
José F. M. Barcellos
Keyword(s):  
Urban Areas ◽  
Folk Medicine ◽  
Experimental Studies ◽  
Experimental Tests ◽  
Stem Bark ◽  
Experimental Models ◽  
Narrative Review ◽  
In Vivo Models ◽  
Methodological Guidelines

Introduction: Jucá or pau-ferro (Libidibia ferrea) is an arboreal plant from the Fabaceae family. It is commonly used in traditional medicine in the treatment of various diseases, including inflammatory process. Aims: The objective of this narrative review is to present botanical aspects, ethnopharmacological properties, phytochemical characteristics, toxicity highlighting, and experimental models with L. ferrea. Results: Botanical Aspects: Jucá has several uses such as in landscaping (stem and canopy), in arborization of urban areas. Ethnopharmacological Properties: It is used in the treatment of various diseases such as diabetes, flu, asthma and, inflammatory processes of which different parts are used (root, stem bark, leaves, fruits, seeds). Phytochemical Characteristics: Phenolic compounds, fatty acids, and terpenoids are among the compounds monthly used. Toxicity: In vivo models have been used to verify toxicity and in most studies the plant presented no toxicity in its use. Experimental studies: Animals, such as mice, dogs, rats, etc. and different models of studies to analyze the action of the plant were used. Conclusions: Such low toxicity, associated with its widespread use in folk medicine and its various effects demonstrated in the studies included in this Review have corroborated for the continuity of the research with L. ferrea. New studies, however, ought to follow methodological guidelines, such as the Animal Research: reporting in vivo Experiments (ARRIVE) so that, a methodological design secures more homogeneous studies capable of quantifying the actual size of the effect in the plant may have in clinical studies.  

scholarly journals Experimental tests for characterization of GPR antenna patterns

1994 ◽  
Vol 37 (5 Sup.) ◽  
Author(s):  
E. Pettinelli ◽  
N. Pierdicca ◽  
S. Piro ◽  
L. Versino
Keyword(s):  
Radiation Pattern ◽  
National Research Council ◽  
Experimental Tests ◽  
Radar Signal ◽  
Antenna Radiation ◽  
Buried Structures ◽  
Antenna Radiation Pattern ◽  
The Difference ◽  
Set Up

Detection and location of buried structures using the electromagnetic impulsive methodologies (GPR) require the study of the spatial distribution of energy irradiated by an antenna into the ground and the mechanisms of wave propagation and scattering from relevant targets. Evaluation of the difference in wave field distribution in the ground with respect to free space can provide some useful indications on the propagation of the Geo-radar signal in the ground and the spatial resolution capability of the GPR method. For this reason, a research group, involving “La Sapienza” University, Rome and the National Research Council began, during 1992, to perform studies on antenna radiation pattern, the propagation and scattering phenomena of GPR. This paper presents the experimental set up and the obtained results on the antenna radiation pattern.

scholarly journals Integrated Passenger Transport System in Rural Areas – A Literature Review

2020 ◽  
Vol 32 (6) ◽  
pp. 863-873
Author(s):  
Branimir Maretić ◽  
Borna Abramović
Keyword(s):  
Literature Review ◽  
Transport System ◽  
Rural Areas ◽  
Urban Areas ◽  
Planning System ◽  
Passenger Transport ◽  
Public Transport System ◽  
Urban And Rural Areas ◽  
Set Up ◽  
The Impact

The planning and organisation of public passenger transport in rural areas is a complex process. The transport demand in rural areas is often low, which makes it hard to establish and run a financially sustainable public transport system. A solution is integrated passenger transport that eliminates deficiencies and provides benefits for all participants in the public passenger transport process. This paper describes the impact of integrated passenger transport on mobility in rural areas and critically evaluates different literature sources. Integration of passenger transport in urban areas has been described in the context of rural areas, and the challenges of integration of public passenger transport specific to rural areas have been analysed. Through the application in urban and rural areas, the planning of integrated and non-integrated passenger transport has been functionally analysed. The analysis found an increase in the degree of mobility in the areas that use integrated passenger transport compared to the non-integrated one. This research of the literature review has identified the rural areas of mobility as under-researched. The mobility research can set up a more efficient passenger transport planning system in rural areas.

scholarly journals Float: Designing for the Rise in Sea Level

2019 ◽  
Author(s):  
Camilo Cerro ◽  
Keyword(s):  
Sea Level ◽  
Urban Areas ◽  
Healthcare Education ◽  
American University ◽  
Real Possibility ◽  
Urban Problem ◽  
Will Force ◽  
Complex Relationships ◽  
Set Up ◽  
Floating Systems

According to the United Nations, presently, about 54% of the world’s population lives in urban areas, with the number expected to increase to 66% by 2050. Urban areas which are ill prepared to deal with their present population needs will have to develop and manage; housing, healthcare, education, transportation, infrastructure and food pro-duction for an additional 2.5 billion people. With three-quarters of the world’s megalopolis by the sea and 80% of people living within 60 miles of the coast, sea level rise will force a new way of thinking about urban development. Managing urban areas has become one of the most important development challenges of the 21st century. In the UAE specifically, there are nearly 1,300 kilometers of coast-line. Approximately 85% of the population and over 90% of the infra-structure are located within several meters of sea level in low-lying coastal areas. This poses a very specific urban problem of relocation. But not all relocation will need to be done inland. The potential for floating architecture is a very real possibility to help solve some of the problems brought on by the rise in sea level. This is why at the American University of Sharjah, we have been studying this issue and other sustainability related opportunities in a series of courses that started in 2014 with a summer studio course set in Cambodia. Students lived with a floating community in the Tong le Sap lake for a month, studying vernacular floatation systems to inform the development of proposals for floating dwelling studies. This semester (Spring 2018), a fifth year architecture studio set up to transfer specific urban functions to the water within protected areas in the UAE. The aim of the studio was to start looking at possible implementation of floating systems within everyday functions to start a discussion of the potential of this technologies and the feasibility of its use at both an industrial and commercial level. The idea was to develop a series systemic interdependent sustainable designs based on the idea of third nature, hybridizing complex relationships between distinct functions in environments above and below water. This paper will cover the methodology implemented to start tackling these subjects in the studio environment with the aim to create awareness for designers and the general public.

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