Study of Self-Similar Traffic Control of Campus Network

The lack of effectiveness of the use of models of self-similar processes to the analysis of queues telecommunications systems is presented. The evolution of the flow models managed by Markovs chain is considered. The specifics of the use of Markovs flows as models of telecommunications traffic systems are considered. Models of single-channel queueing systems with input flows that have an arbitrary correlation are presented. Generalizations of the Khinchin-Pollaczek formula are given for these systems. The perspective of the application of interval methods developed by the author for queue analysis in queueing systems with correlated input flows is shown. It is suggested to use the group Poisson extraordinary flow as a model of telecommunication traffic. Interval characteristics of the given flows are reviewed and the prospects of their application are shown. The issues of multiplexing these flows during processing in queueing systems are considered. It is demonstrated that the resulting flow is also a group Poisson flow when summing up several group Poisson flows. The conclusions are confirmed by the simulation modeling results. The examples show the validity of such models to the characteristics of real video traffic flows.

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Workload Perception of Air Traffic Control Officers and Pilots During Continuous Descent Operations Approach Procedures

Aviation Psychology and Applied Human Factors ◽

10.1027/2192-0923/a000154 ◽

2019 ◽

Vol 9 (1) ◽

pp. 2-11

Author(s):

Marina Efthymiou ◽

Frank Fichert ◽

Olaf Lantzsch

Keyword(s):

Fuel Consumption ◽

Traffic Control ◽

Air Traffic Control ◽

Negative Impact ◽

Air Traffic ◽

Reduce Fuel Consumption ◽

Total Load ◽

Open Path

Abstract. The paper examines the workload perceived by air traffic control officers (ATCOs) and pilots during continuous descent operations (CDOs), applying closed- and open-path procedures. CDOs reduce fuel consumption and noise emissions. Therefore, they are supported by airports as well as airlines. However, their use often depends on pilots asking for CDOs and controllers giving approval and directions. An adapted NASA Total Load Index (TLX) was used to measure the workload perception of ATCOs and pilots when applying CDOs at selected European airports. The main finding is that ATCOs’ workload increased when giving both closed- and open-path CDOs, which may have a negative impact on their willingness to apply CDOs. The main problem reported by pilots was insufficient distance-to-go information provided by ATCOs. The workload change is important when considering the use of CDOs.

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How to Evaluate Remote Tower Metrics in Connection With Weather Observations

Aviation Psychology and Applied Human Factors ◽

10.1027/2192-0923/a000142 ◽

2018 ◽

Vol 8 (2) ◽

pp. 100-111 ◽

Cited By ~ 1

Author(s):

Maik Friedrich ◽

Christoph Möhlenbrink

Keyword(s):

Traffic Control ◽

Air Traffic Control ◽

Influential Factors ◽

Air Traffic ◽

Weather Event ◽

Evaluation Of Performance ◽

Weather Events ◽

Weather Observations ◽

Validation Experiment ◽

Remote Controller

Abstract. Owing to the different approaches for remote tower operation, a standardized set of indicators is needed to evaluate the technical implementations at a task performance level. One of the most influential factors for air traffic control is weather. This article describes the influence of weather metrics on remote tower operations and how to validate them against each other. Weather metrics are essential to the evaluation of different remote controller working positions. Therefore, weather metrics were identified as part of a validation at the Erfurt-Weimar Airport. Air traffic control officers observed weather events at the tower control working position and the remote control working position. The eight participating air traffic control officers answered time-synchronized questionnaires at both workplaces. The questionnaires addressed operationally relevant weather events in the aerodrome. The validation experiment targeted the air traffic control officer’s ability to categorize and judge the same weather event at different workplaces. The results show the potential of standardized indicators for the evaluation of performance and the importance of weather metrics in relation to other evaluation metrics.

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