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Tarik Kazaz, M. Coutiño, G. Janssen, G. Leus, A. V. D. Veen

Synchronization and ranging in internet of things $(IoT)$ networks are challenging due to the narrowband nature of signals used for communication between IoT nodes. Recently, several estimators for range estimation using phase difference of arrival $(PDoA)$ measurements of narrowband signals have been proposed. However, these estimators are based on data models which do not consider the impact of clock-skew on the range estimation. In this paper, clock-skew and range estimation are studied under a unified framework. We derive a novel and precise data model for PDoA measurements which incorporates the unknown clock-skew effects. We then formulate joint estimation of the clock-skew and range as a two-dimensional (2-D) frequency estimation problem of a single complex sinusoid. Furthermore, we propose: (i) a two-way communication protocol for collecting PDoA measurements and (ii) a weighted least squares (WLS) algorithm for joint estimation of clock-skew and range leveraging the shift invariance property of the measurement data. Finally, through numerical experiments, the performance of the proposed protocol and estimator is compared against the Cramér Rao lower bound demonstrating that the proposed estimator is asymptotically efficient.

Fault location estimation is a very important question in electric power system, in order to isolate the fault as soon as possible, and to recover the system with minimal interruptions. In that way, electric equipment is less stressed, and buyers more satisfied. Electric power lines are exposed to environment and probability of line failure is generally higher than other system element failure. Current electric power systems are equipped with high sampling rate power quality meters that are installed in the places of common coupling with distribution systems or high voltage consumers. Data obtained by these power quality meters, especially the voltage and current harmonics present a valuable information about system behavior, even in the faulty conditions. In this paper fault location and fault resistance is estimated by using a combination of artificial neural networks and voltage and current harmonics measured by power quality meters installed only in important system busbars. Results obtained from the real 110 kV transmission system show that a proposed algorithm can be used successfully in fault location and fault resistance estimation in one part of the electric power system. This paper makes a contribution to the existing body of knowledge by developing and testing a new method whose application represents a natural and a feasible upgrade using the existing measurement and communication equipment.

J. Gainer, M. González-Alonso, A. Greljo, Senad Isaković, G. Isidori, A. Korytov, J. Lykken, D. Marzocca et al.

The “golden” channel, in which the newly-discovered Higgs boson decays to four leptons by means of intermediate vector bosons, is important for determining the properties of the Higgs boson and for searching for subtle new physics effects. Different approaches exist for parametrizing the relevant Higgs couplings in this channel; here we relate the use of pseudo-observables to methods based on specifying the most general amplitude or Lagrangian terms for the HVV interactions. We also provide projections for sensitivity in this channel in several novel scenarios, illustrating the use of pseudo-observables, and analyze the role of kinematic distributions and (ratios of) rates in such H → 4ℓ studies.

N. Papac-Miličević, L. Alic, D. Czamara, Michael Gurbisz, M. Ozsvár-Kozma, Stefanie Haslinger-Hutter, G. Hoermann, C. Skerka et al.

M. Rao, Admir Kaknjo, E. Omerdic, D. Toal, T. Newe

The LabVIEW FPGA platform is based on graphical programming approach, which makes easy the FPGA programming and the I/O interfacing. The LabVIEW FPGA significantly improves the design productivity and helps to reduce the time to market. On the other hand, traditional FPGA platform is helpful to get an efficient/optimized design by providing control over each bit using HDL programming languages. This work utilized traditional as well as LabVIEW FPGA platforms to get an optimized high speed design of AES (Advanced Encryption Standard). The AES is considered to be a secure and reliable cryptographic algorithm that is used worldwide to provide encryption services, which hide the information during communication over untrusted networks, like Internet. Here, AES core is proposed to secure the communication between ROV (Remotely Operated Vehicle) and control station in a marine environment; but this core can be fit in any other high speed electronic communications. This work provides encryption of 128-bytes, 256-bytes and 512-bytes set of inputs (individually and simultaneously) using a 128-bit key. In case of simultaneous implementation, all the above mentioned set of inputs is encrypted in parallel. This simultaneous implementation is resulted in throughput of Gbps range.

Burak Oztoprak, Eray A. Baran, A. Sabanoviç

This paper proposes a method for the scaled bilateral teleoperation with continuously variable position and force scaling. In the proposed method, the controller is reformulated to synchronize the forces and velocities which provides the operator with the ability to change the scaling gains during operation. For the derivation of the controller, exponentially decaying error dynamics are preferred over the assumption of disturbance compensation with Disturbance Observers (DOB). Following the mathematical derivation, the algorithm is tested on a setup containing single DOF master and slave robots with the ability of giving force feedback to the operator. In order to provide a complete analysis, several different sets of experiments are made with sinusoidal velocity and force scales having different amplitudes and frequencies. Experiment results illustrate the successful tracking responses and stable operation of the proposed control scheme for the continuously varying velocity and force scales.

B. Muslu, Burak Oztoprak, Eray A. Baran, A. Sabanoviç

This paper presents a controller structure for the continuous and robust modification of motion for multi body systems encountering contact with an environment during free motion. The presented algorithm relies on the reformulation of the position tracking error with a term proportional to the reaction force. With the proposed method, fusion of the position and the force controllers can be achieved which provide the robot with certain level of compliance. The derivation of the proposed method is followed by experiments made on a pantograph mechanism actuated by direct drive linear motors. The results obtained from the experiments illustrate the success of the proposed control architecture in providing a natural behavior for the robotic systems working in constrained environments.

E. Lambert, H. Morais, F. Reis, R. Alves, G. Taylor, A. Souvent, N. Suljanovic

This article gives an overview of TSO-DSO data exchanges when face the challenges posed by distributed energy resources and flexibility services in the distribution grid. Roles of TSOs and DSOs in the coordinated power system architecture are explained and use cases for TSO-DSO data exchange are provided. ICT architecture that supports data exchange in the coordinated power system is presented, with commonly used protocols. Additionally, the application of Internet of Things architecture is presented as a technology enabler for TSO-DSO data exchange in the near future. This paper is based on the H2020 TDX-ASSIST (www.tdx-assist.eu) deliverable D1.1 “TSO-DSO state of the art”.

K. Anoh, D. Bajović, D. Vukobratović, B. Adebisi, D. Jakovetić, M. Cosovic

Distributed energy trading among energy prosumers (i.e., energy producers that also consume energy) is expected to bring significant cost benefits for the participating actors. In terms of the system architecture, physical grouping into microgrids (MG) can be further enhanced by communication infrastructure that provides support for flexible organization of prosumers into virtual MGs. However, how to manage prosumers using communication infrastructure is not widely investigated. In this paper, we propose a virtual MG architecture induced by communication constraints and consider its impact on total costs of energy trading. More precisely, we refine the distributed energy trading model considered in the recent literature with additional communication constraints and investigate impact of the resulting virtualized MG architecture on the overall energy trading costs. We show by simulations that there indeed exists an optimal energy trading architecture that achieves minimum possible energy trading cost, for any given model parameters.

Roberta Perković, Ana Sučić, I. Vasilj, B. Krišto

Introduction: The most common mental disorders in elderly, beside dementia, are depression and anxiety, which are important public health problem, although they are diagnosed and treated in under 20% of the population. Mental health care for elderly is one of the indicators of quality or omissions in the health system of a country. Aim: The aim of the study was to examine the incidence of depression and anxiety among the elderly in the Livno area. Material and methods: Across-sectional study was carried out in the Livno area through June 2017 on a sample of 100 respondents (N=100). Inclusion criteria: age over 65 years. Exclusion criteria: persons with malignancy, persons with psychiatric diagnosis or dementia. Research tools used: Questionnaire on sociodemographic status and Hospital Anxiety and Depression Self Evaluation Scale (HAD). Results: More than 90% of the respondents of both genders were estimated to be borderline depressed or depressed. There was a higher incidence of depression among male respondents, and anxiety among female respondents. Probably and borderline anxiety is recorded in 84% of respondents, which exceed the results of all available literature data. Religious habits have no influence on the occurrence of depression but there is a connection between prayer and anxiety occurrence. Conclusion: This research has established an extremely high incidence of depression and anxiety among the elderly in the Livno area. The results of the available studies indicate significantly lower rates of occurrence than in the tested sample. Socioeconomic status did not prove to be a significant predictor of the occurrence of these disorders.

A fuzzy formula does not necessarily follow from a set of fuzzy formulas. In the case when fuzzy formulas and fuzzy dependencies are mutually identified, the corresponding equivalent statement has an obvious meaning. An affirmative statement, however, rises the question of automatization. In our earlier research, we offered an efficient algorithm based on application of selected fuzzy logic operators and resolution principle. In this paper we prove that those ingredients of the algorithm that explicitly depend on the choice of fuzzy implication operator, hold also true for the class of g-generated fuzzy implications.

A. Martini, A. Ravelli, T. Avčin, M. Beresford, R. Burgos-Vargas, R. Cuttica, N. Ilowite, R. Khubchandani et al.

Objective. To revise the current juvenile idiopathic arthritis (JIA) International League of Associations for Rheumatology (ILAR) classification criteria with an evidence-based approach, using clinical and routine laboratory measures available worldwide, to identify homogeneous clinical groups and to distinguish those forms of chronic arthritis typically seen only in children from the childhood counterpart of adult diseases. Methods. The overall project consists of 4 steps. This work represents Step 1, a Delphi Web-based consensus and Step 2, an international nominal group technique (NGT) consensus conference for the new provisional Pediatric Rheumatology International Trials Organization JIA classification criteria. A future large data collection of at least 1000 new-onset JIA patients (Step 3) followed by analysis and NGT consensus (Step 4) will provide data for the evidence-based validation of the JIA classification criteria. Results. In Step 1, three Delphi rounds of interactions were implemented to revise the 7 ILAR JIA categories. In Step 2, forty-seven questions with electronic voting were implemented to derive the new proposed criteria. Four disorders were proposed: (a) systemic JIA; (b) rheumatoid factor–positive JIA; (c) enthesitis/spondylitis-related JIA; and (d) early-onset antinuclear antibody–positive JIA. The other forms were gathered under the term “others.” These will be analyzed during the prospective data collection using a list of descriptors to see whether the clustering of some of them could identify homogeneous entities. Conclusion. An international consensus was reached to identify different proposed homogeneous chronic disorders that fall under the historical term JIA. These preliminary criteria will be formally validated with a dedicated project.

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