Visible to the public Biblio

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2019-09-30
Liu, Y., Li, L., Gao, Q., Cao, J., Wang, R., Sun, Z..  2019.  Analytical Model of Torque-Prediction for a Novel Hybrid Rotor Permanent Magnet Machines. IEEE Access. 7:109528–109538.

This paper presents an analytical method for predicting the electromagnetic performance in permanent magnet (PM) machine with the spoke-type rotor (STR) and a proposed hybrid rotor structure (HRS), respectively. The key of this method is to combine magnetic field analysis model (MFAM) with the magnetic equivalent circuit model. The influence of the irregular PM shape is considered by the segmentation calculation. To obtain the boundary condition in the MFAM, respectively, two equivalent methods on the rotor side are proposed. In the STR, the average flux density of the rotor core outer-surface is calculated to solve the Laplace's equation with considering for the rotor core outer-surface eccentric. In the HRS, based on the Thevenin's theorem, the equivalent parameters of PM remanence BreB and thickness hpme are obtained as a given condition, which can be utilized to compute the air-gap flux density by conventional classic magnetic field analysis model of surface-mounted PMs with air-gap region. Finally, the proposed analytical models are verified by the finite element analysis (FEA) with comparisons of the air-gap flux density, flux linkage, back-EMF and electromagnetic torque, respectively. Furthermore, the performance that the machine with the proposed hybrid structure rotor can improve the torque density as explained.

2018-11-14
Pavlenko, P., Tavrov, D., Temnikov, V., Zavgorodniy, S., Temnikov, A..  2018.  The Method of Expert Evaluation of Airports Aviation Security Using Perceptual Calculations. 2018 IEEE 9th International Conference on Dependable Systems, Services and Technologies (DESSERT). :406–410.
One of the effective ways to improve the quality of airport security (AS) is to improve the quality of management of the state of the system for countering acts of unlawful interference by intruders into the airports (SCAUI), which is a set of AS employees, technical systems and devices used for passenger screening, luggage, other operational procedures, as well as to protect the restricted areas of the airports. Proactive control of the SCAUI state includes ongoing conducting assessment of airport AS quality by experts, identification of SCAUI elements (functional state of AS employees, characteristics of technical systems and devices) that have a predominant influence on AS, and improvement of their performance. This article presents principles of the model and the method for conducting expert quality assessment of airport AS, whose application allows to increase the efficiency and quality of AS assessment by experts, and, consequently, the quality of SCAUI state control.
2018-09-05
Pasareanu, C..  2017.  Symbolic execution and probabilistic reasoning. 2017 32nd Annual ACM/IEEE Symposium on Logic in Computer Science (LICS). :1–1.
Summary form only given. Symbolic execution is a systematic program analysis technique which explores multiple program behaviors all at once by collecting and solving symbolic path conditions over program paths. The technique has been recently extended with probabilistic reasoning. This approach computes the conditions to reach target program events of interest and uses model counting to quantify the fraction of the input domain satisfying these conditions thus computing the probability of event occurrence. This probabilistic information can be used for example to compute the reliability of an aircraft controller under different wind conditions (modeled probabilistically) or to quantify the leakage of sensitive data in a software system, using information theory metrics such as Shannon entropy. In this talk we review recent advances in symbolic execution and probabilistic reasoning and we discuss how they can be used to ensure the safety and security of software systems.
2018-02-06
Brust, M. R., Zurad, M., Hentges, L., Gomes, L., Danoy, G., Bouvry, P..  2017.  Target Tracking Optimization of UAV Swarms Based on Dual-Pheromone Clustering. 2017 3rd IEEE International Conference on Cybernetics (CYBCONF). :1–8.

Unmanned Aerial Vehicles (UAVs) are autonomous aircraft that, when equipped with wireless communication interfaces, can share data among themselves when in communication range. Compared to single UAVs, using multiple UAVs as a collaborative swarm is considerably more effective for target tracking, reconnaissance, and surveillance missions because of their capacity to tackle complex problems synergistically. Success rates in target detection and tracking depend on map coverage performance, which in turn relies on network connectivity between UAVs to propagate surveillance results to avoid revisiting already observed areas. In this paper, we consider the problem of optimizing three objectives for a swarm of UAVs: (a) target detection and tracking, (b) map coverage, and (c) network connectivity. Our approach, Dual-Pheromone Clustering Hybrid Approach (DPCHA), incorporates a multi-hop clustering and a dual-pheromone ant-colony model to optimize these three objectives. Clustering keeps stable overlay networks, while attractive and repulsive pheromones mark areas of detected targets and visited areas. Additionally, DPCHA introduces a disappearing target model for dealing with temporarily invisible targets. Extensive simulations show that DPCHA produces significant improvements in the assessment of coverage fairness, cluster stability, and connection volatility. We compared our approach with a pure dual- pheromone approach and a no-base model, which removes the base station from the model. Results show an approximately 50% improvement in map coverage compared to the pure dual-pheromone approach.

2017-12-28
Mailloux, L. O., Sargeant, B. N., Hodson, D. D., Grimaila, M. R..  2017.  System-level considerations for modeling space-based quantum key distribution architectures. 2017 Annual IEEE International Systems Conference (SysCon). :1–6.

Quantum Key Distribution (QKD) is a revolutionary technology which leverages the laws of quantum mechanics to distribute cryptographic keying material between two parties with theoretically unconditional security. Terrestrial QKD systems are limited to distances of \textbackslashtextless;200 km in both optical fiber and line-of-sight free-space configurations due to severe losses during single photon propagation and the curvature of the Earth. Thus, the feasibility of fielding a low Earth orbit (LEO) QKD satellite to overcome this limitation is being explored. Moreover, in August 2016, the Chinese Academy of Sciences successfully launched the world's first QKD satellite. However, many of the practical engineering performance and security tradeoffs associated with space-based QKD are not well understood for global secure key distribution. This paper presents several system-level considerations for modeling and studying space-based QKD architectures and systems. More specifically, this paper explores the behaviors and requirements that researchers must examine to develop a model for studying the effectiveness of QKD between LEO satellites and ground stations.

2017-12-20
Mishra, S. K., Patel, A..  2017.  Wells turbine modeling and PI control scheme for OWC plant using Xilinx system generator. 2017 4th International Conference on Power, Control Embedded Systems (ICPCES). :1–6.

This paper develops a model for Wells turbine using Xilinx system generator (XSG)toolbox of Matlab. The Wells turbine is very popular in oscillating water column (OWC) wave energy converters. Mostly, the turbine behavior is emulated in a controlled DC or AC motor coupled with a generator. Therefore, it is required to model the OWC and Wells turbine in real time software like XSG. It generates the OWC turbine behavior in real time. Next, a PI control scheme is suggested for controlling the DC motor so as to emulate the Wells turbine efficiently. The overall performance of the system is tested with asquirrel cage induction generator (SCIG). The Pierson-Moskowitz and JONSWAP irregular wave models have been applied to validate the OWC model. Finally, the simulation results for Wells turbine and PI controller have beendiscussed.

2017-12-12
Stephan, E., Raju, B., Elsethagen, T., Pouchard, L., Gamboa, C..  2017.  A scientific data provenance harvester for distributed applications. 2017 New York Scientific Data Summit (NYSDS). :1–9.

Data provenance provides a way for scientists to observe how experimental data originates, conveys process history, and explains influential factors such as experimental rationale and associated environmental factors from system metrics measured at runtime. The US Department of Energy Office of Science Integrated end-to-end Performance Prediction and Diagnosis for Extreme Scientific Workflows (IPPD) project has developed a provenance harvester that is capable of collecting observations from file based evidence typically produced by distributed applications. To achieve this, file based evidence is extracted and transformed into an intermediate data format inspired in part by W3C CSV on the Web recommendations, called the Harvester Provenance Application Interface (HAPI) syntax. This syntax provides a general means to pre-stage provenance into messages that are both human readable and capable of being written to a provenance store, Provenance Environment (ProvEn). HAPI is being applied to harvest provenance from climate ensemble runs for Accelerated Climate Modeling for Energy (ACME) project funded under the U.S. Department of Energy's Office of Biological and Environmental Research (BER) Earth System Modeling (ESM) program. ACME informally provides provenance in a native form through configuration files, directory structures, and log files that contain success/failure indicators, code traces, and performance measurements. Because of its generic format, HAPI is also being applied to harvest tabular job management provenance from Belle II DIRAC scheduler relational database tables as well as other scientific applications that log provenance related information.

2017-03-08
Finn, J., Nuzzo, P., Sangiovanni-Vincentelli, A..  2015.  A mixed discrete-continuous optimization scheme for Cyber-Physical System architecture exploration. 2015 IEEE/ACM International Conference on Computer-Aided Design (ICCAD). :216–223.

We propose a methodology for architecture exploration for Cyber-Physical Systems (CPS) based on an iterative, optimization-based approach, where a discrete architecture selection engine is placed in a loop with a continuous sizing engine. The discrete optimization routine proposes a candidate architecture to the sizing engine. The sizing routine optimizes over the continuous parameters using simulation to evaluate the physical models and to monitor the requirements. To decrease the number of simulations, we show how balance equations and conservation laws can be leveraged to prune the discrete space, thus achieving significant reduction in the overall runtime. We demonstrate the effectiveness of our methodology on an industrial case study, namely an aircraft environmental control system, showing more than one order of magnitude reduction in optimization time.

2017-03-07
Ugwoke, F. N., Okafor, K. C., Chijindu, V. C..  2015.  Security QoS profiling against cyber terrorism in airport network systems. 2015 International Conference on Cyberspace (CYBER-Abuja). :241–251.

Attacks on airport information network services in the form of Denial of Service (DoS), Distributed DoS (DDoS), and hijacking are the most effective schemes mostly explored by cyber terrorists in the aviation industry running Mission Critical Services (MCSs). This work presents a case for Airport Information Resource Management Systems (AIRMS) which is a cloud based platform proposed for the Nigerian aviation industry. Granting that AIRMS is susceptible to DoS attacks, there is need to develop a robust counter security network model aimed at pre-empting such attacks and subsequently mitigating the vulnerability in such networks. Existing works in literature regarding cyber security DoS and other schemes have not explored embedded Stateful Packet Inspection (SPI) based on OpenFlow Application Centric Infrastructure (OACI) for securing critical network assets. As such, SPI-OACI was proposed to address the challenge of Vulnerability Bandwidth Depletion DDoS Attacks (VBDDA). A characterization of the Cisco 9000 router firewall as an embedded network device with support for Virtual DDoS protection was carried out in the AIRMS threat mitigation design. Afterwards, the mitigation procedure and the initial phase of the design with Riverbed modeler software were realized. For the security Quality of Service (QoS) profiling, the system response metrics (i.e. SPI-OACI delay, throughput and utilization) in cloud based network were analyzed only for normal traffic flows. The work concludes by offering practical suggestion for securing similar enterprise management systems running on cloud infrastructure against cyber terrorists.

2015-05-06
Musgrove, J., Cukic, B., Cortellessa, V..  2014.  Proactive Model-Based Performance Analysis and Security Tradeoffs in a Complex System. High-Assurance Systems Engineering (HASE), 2014 IEEE 15th International Symposium on. :211-215.

Application domains in which early performance evaluation is needed are becoming more complex. In addition to traditional measures of complexity due, for example, to the number of components, their interactions, complicated control coordination and schemes, emerging applications may require adaptive response and reconfiguration the impact of externally observable (security) parameters. In this paper we introduce an approach for effective modeling and analysis of performance and security tradeoffs. The approach identifies a suitable allocation of resources that meet performance requirements, while maximizing measurable security effects. We demonstrate this approach through the analysis of performance sensitivity of a Border Inspection Management System (BIMS) with changing security mechanisms (e.g. biometric system parameters for passenger identification). The final result is a model-based approach that allows us to take decisions about BIMS performance and security mechanisms on the basis of rates of traveler arrivals and traveler identification security guarantees. We describe the experience gained when applying this approach to daily flight arrival schedule of a real airport.

2015-05-05
Amin, S., Clark, T., Offutt, R., Serenko, K..  2014.  Design of a cyber security framework for ADS-B based surveillance systems. Systems and Information Engineering Design Symposium (SIEDS), 2014. :304-309.

The need for increased surveillance due to increase in flight volume in remote or oceanic regions outside the range of traditional radar coverage has been fulfilled by the advent of space-based Automatic Dependent Surveillance — Broadcast (ADS-B) Surveillance systems. ADS-B systems have the capability of providing air traffic controllers with highly accurate real-time flight data. ADS-B is dependent on digital communications between aircraft and ground stations of the air route traffic control center (ARTCC); however these communications are not secured. Anyone with the appropriate capabilities and equipment can interrogate the signal and transmit their own false data; this is known as spoofing. The possibility of this type of attacks decreases the situational awareness of United States airspace. The purpose of this project is to design a secure transmission framework that prevents ADS-B signals from being spoofed. Three alternative methods of securing ADS-B signals are evaluated: hashing, symmetric encryption, and asymmetric encryption. Security strength of the design alternatives is determined from research. Feasibility criteria are determined by comparative analysis of alternatives. Economic implications and possible collision risk is determined from simulations that model the United State airspace over the Gulf of Mexico and part of the airspace under attack respectively. The ultimate goal of the project is to show that if ADS-B signals can be secured, the situational awareness can improve and the ARTCC can use information from this surveillance system to decrease the separation between aircraft and ultimately maximize the use of the United States airspace.

Ponti, C., Pajewski, L., Schettini, G..  2014.  Simulation of scattering by cylindrical targets hidden behind a layer. Ground Penetrating Radar (GPR), 2014 15th International Conference on. :560-564.

Through-wall sensing of hidden objects is a topic that is receiving a wide interest in several application contexts, especially in the field of security. The success of the object retrieval relies on accurate scattering models as well as on reliable inversion algorithms. In this paper, a contribution to the modeling of direct scattering for Through-Wall Imaging applications is given. The approach deals with hidden scatterers that are circular cross-section metallic cylinders placed below a dielectric layer, and it is based on an analytical-numerical technique implementing Cylindrical Wave Approach. As the burial medium of the scatterers may be a dielectric of arbitrary permittivity, general problems of scattering by hidden objects may be considered.When the burial medium is filled with air, the technique can simulate objects concealed in a building interior. Otherwise, simulation of geophysical problems of targets buried in a layered soil can be performed. Numerical results of practical cases are reported in the paper, showing the potentialities of the technique for its use in inversion algorithms.
 

2015-05-01
Lichen Zhang.  2014.  Convergence of physical system and cyber system modeling methods for aviation cyber physical control system. Information and Automation (ICIA), 2014 IEEE International Conference on. :542-547.

Recent attention to aviation cyber physical systems (ACPS) is driven by the need for seamless integration of design disciplines that dominate physical world and cyber world convergence. System convergence is a big obstacle to good aviation cyber-physical system (ACPS) design, which is due to a lack of an adequate scientific theoretical foundation for the subject. The absence of a good understanding of the science of aviation system convergence is not due to neglect, but rather due to its difficulty. Most complex aviation system builders have abandoned any science or engineering discipline for system convergence they simply treat it as a management problem. Aviation System convergence is almost totally absent from software engineering and engineering curricula. Hence, system convergence is particularly challenging in ACPS where fundamentally different physical and computational design concerns intersect. In this paper, we propose an integrated approach to handle System convergence of aviation cyber physical systems based on multi-dimensions, multi-views, multi-paradigm and multiple tools. This model-integrated development approach addresses the development needs of cyber physical systems through the pervasive use of models, and physical world, cyber world can be specified and modeled together, cyber world and physical world can be converged entirely, and cyber world models and physical world model can be integrated seamlessly. The effectiveness of the approach is illustrated by means of one practical case study: specifying and modeling Aircraft Systems. In this paper, We specify and model Aviation Cyber-Physical Systems with integrating Modelica, Modelicaml and Architecture Analysis & Design Language (AADL), the physical world is modeled by Modelica and Modelicaml, the cyber part is modeled by AADL and Modelicaml.

2015-04-30
Di Benedetto, M.D., D'Innocenzo, A., Smarra, F..  2014.  Fault-tolerant control of a wireless HVAC control system. Communications, Control and Signal Processing (ISCCSP), 2014 6th International Symposium on. :235-238.

In this paper we address the problem of designing a fault tolerant control scheme for an HVAC control system where sensing and actuation data are exchanged with a centralized controller via a wireless sensors and actuators network where the communication nodes are subject to permanent failures and malicious intrusions.