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1 – 9 of 9Irfan Sayim and Dan Zhang
The purpose of this work is to obtain an overbounded broadcast sigma from actual (non-Gaussian) correction error distribution under the stringent navigation integrity requirements…
Abstract
Purpose
The purpose of this work is to obtain an overbounded broadcast sigma from actual (non-Gaussian) correction error distribution under the stringent navigation integrity requirements for aircraft precision approach and landing.
Design/methodology/approach
Approach is statistically to overbound satellite pseudorange correction error distribution with the use of numerical solution of Fisher-Z transformation. Inflation factors for overbounding broadcast sigma are extracted from Fisher-Z transformation based on measured correlation and counted independent identically distributed (iid) sample sizes of true empirical data.
Findings
New overbounded broadcast sigma values for eight long-pass satellites were obtained based on measured actual empirical data and ensured integrity risk at 10−8 probability level. Proposed methodology successfully overbounds ground reflection multipath-type systematic and temporal errors sources.
Originality/value
This paper introduced a new method of accounting for ground reflection multipath for local area augmentation system/ground-based augmentation system navigation integrity. The method is also applicable to statistically overbound any other serially correlated temporal variation in measured data if both correlation values and finite iid sample sizes are known.
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Meaghan Botterill and Barbara de la Harpe
Working in interdisciplinary teams is recognised as fundamental to contemporary workplaces in the knowledge economy. Current research across the disciplines clearly shows that…
Abstract
Working in interdisciplinary teams is recognised as fundamental to contemporary workplaces in the knowledge economy. Current research across the disciplines clearly shows that working successfully in interdisciplinary teams is associated with increased productivity, improved outcomes, higher levels of creativity and enhanced personal fulfilment. But why is there a perception that it is hard to work in such teams in higher education contexts, and what does it take to work successfully in an interdisciplinary team? In this chapter we use embedded intergroup relations theory as a way of conceptualising the tensions and complexities that exist within interdisciplinary teams in universities. We draw on the constructs of group membership, parallel processes, group boundaries, power differences, affective patterns, cognitive formations and leadership behaviours to deconstruct why working in interdisciplinary teams often challenges academic identities, cultures and contexts. We then consider the core factors that underpin successful interdisciplinary teams, based on a synthesis of the work in the fields of social sciences, organisational behaviour, education, health and psychology. Understanding the complexities of working in interdisciplinary teams within universities provides insights into how to facilitate positive outcomes for all involved in interdisciplinary teamwork.
Michael Felux, Thomas Dautermann and Hayung Becker
The purpose of this paper is to show the performance during flight tests of the proposed GBAS Approach Service Type D navigation – intended to support autoland operations – in…
Abstract
Purpose
The purpose of this paper is to show the performance during flight tests of the proposed GBAS Approach Service Type D navigation – intended to support autoland operations – in comparison to ILS.
Design/methodology/approach
An experimental GBAS station was installed at the research airport in Braunschweig. Data processing complied with the currently proposed requirements to support automatic landings. Corrections for GPS measurements and integrity parameters were sent to a research aircraft which was equipped with an experimental GPS receiver providing raw measurement data. The received data and measurements were then processed on board in real‐time and provide approach guidance information to the experimental pilot in form of a flight director indication. To evaluate system performance the authors create a truth reference track from a post processed carrier phase solution. Finally, the GBAS outputs and the received ILS signals are compared to the truth reference.
Findings
The system performed well within all specifications and showed full availability at all times during the flight. Compared to ILS, GBAS is significantly more precise and shows almost no noise.
Research limitations/implications
The navigation solution was flown manually according to flight director displays, therefore no automatic approaches and landings could be performed.
Practical implications
It has been demonstrated that GBAS can support the intended operations under nominal conditions.
Originality/value
This work is part of the ongoing validation of the proposed standards for a satellite based landing system. It compares GBAS and ILS data from flight tests carried out with a representative aircraft.
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Mary Zellmer-Bruhn, Mary J Waller and Deborah Ancona
This chapter examines the relationship between team routines and temporal entrainment. While the process of entrainment generally reinforces the routines that teams follow…
Abstract
This chapter examines the relationship between team routines and temporal entrainment. While the process of entrainment generally reinforces the routines that teams follow temporal entrainment also creates opportunities for externally focused teams to change their routines. Entrainment creates team rhythms that include pauses in activity that can act as triggers to change. These pauses alone are not enough to impel teams to change; managers must also employ temporal design to make use of these opportunities for change. Both the rhythms of temporal entrainment and the pauses that accompany them are part of a team’s task environment. By uncovering key rhythms, as well as by managing the pauses, managers can both reinforce desired routines and change problematic ones.
This issue's Stack attacks the question of how leaders can move from what they want to achieve to actually achieving it through themselves, teams, peers, and their organizations…
Abstract
This issue's Stack attacks the question of how leaders can move from what they want to achieve to actually achieving it through themselves, teams, peers, and their organizations. The most successful are Execution, First Among Equals, and The Leadership Secrets of Colin Powell. All three can manage to satisfy strategy's old hands and newcomers alike.
Jacqueline Reed and Maria Vakola
This research sets out to examine how the process for developing a training needs analysis tool could influence organisational change.
Abstract
Purpose
This research sets out to examine how the process for developing a training needs analysis tool could influence organisational change.
Design/methodology/approach
The organisation that is the subject of this research is a large, complex health system which is in transition from a traditional bureaucratic, hierarchy with a command and control management style to a more participative, people centred approach. A processual, organisation development, action research‐based approach to the development of a training needs analysis process was taken in the study so that the changes desired in the organisation could be modelled in the first instance and secondly, in order to learn and understand more about what works and does not in order to continuously develop and progress the change agenda. In order to do this a parallel structure was established through which to progress the process which was tracked in an action research process. In addition, a series of interviews were conducted with top and senior management in order to ascertain their views about the process, its necessity, roles in relation to it, its potential benefits and how to introduce the process across the organisation.
Findings
A number of key points emerged from the research: first, the culture and change issues arising during the development of the learning and development needs analysis process were very significant. Second, the development and piloting of the needs analysis process needed to be approached as a change management process. Third, linking the needs analysis process with existing organisational processes was a key factor in the success of the process and created a strategic dimension. Finally, in a large, complex organisation a balance must be struck between standardisation and customisation of the needs analysis process to allow for the different structures, subcultures and levels of readiness in the organisation.
Originality/value
This research highlighted the significant impact the dynamics of hierarchy and the legacy of a bureaucratic, autocratic system has on the way a system operates and how people react to change and participation.
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Ali Fazli and Mohammad Hosein Kazemi
This paper aims to propose a new linear parameter varying (LPV) controller for the robot tracking control problem. Using the identification of the robot dynamics in different work…
Abstract
Purpose
This paper aims to propose a new linear parameter varying (LPV) controller for the robot tracking control problem. Using the identification of the robot dynamics in different work space points about modeling trajectory based on the least square of error algorithm, an LPV model for the robotic arm is extracted.
Design/methodology/approach
Parameter set mapping based on parameter component analysis results in a reduced polytopic LPV model that reduces the complexity of the implementation. An approximation of the required torque is computed based on the reduced LPV models. The state-feedback gain of each zone is computed by solving some linear matrix inequalities (LMIs) to sufficiently decrease the time derivative of a Lyapunov function. A novel smoothing method is used for the proposed controller to switch properly in the borders of the zones.
Findings
The polytopic set of the resulting gains creates the smooth switching polytopic LPV (SS-LPV) controller which is applied to the trajectory tracking problem of the six-degree-of-freedom PUMA 560 robotic arm. A sufficient condition ensures that the proposed controller stabilizes the polytopic LPV system against the torque estimation error.
Practical implications
Smoothing of the switching LPV controller is performed by defining some tolerances and creating some quasi-zones in the borders of the main zones leading to the compressed main zones. The proposed torque estimation is not a model-based technique; so the model variation and other disturbances cannot destroy the performance of the suggested controller. The proposed control scheme does not have any considerable computational load, because the control gains are obtained offline by solving some LMIs, and the torque computation is done online by a simple polytopic-based equation.
Originality/value
In this paper, a new SS-LPV controller is addressed for the trajectory tracking problem of robotic arms. Robot workspace is zoned into some main zones in such a way that the number of models in each zone is almost equal. Data obtained from the modeling trajectory is used to design the state-feedback control gain.
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