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In parachute equipment where in a stabilizing parachute stabilizes an aviator during a free fall, a barometric device, armed by the same act as the release of the stabilizing…
Abstract
In parachute equipment where in a stabilizing parachute stabilizes an aviator during a free fall, a barometric device, armed by the same act as the release of the stabilizing parachute, is provided which at a predetermined altitude, frees a main parachute for withdrawal by the stabilizer. A pack 10 formed with harness 12 and waist belt 13 comprises a front flap 14 and top and side flaps 15 and 16 interconnected by cones 17 locked by pins 18. The interior of the pack is divided into two compartments 23 and 24 by flaps 19 and 20 secured together by loops 21 engaged by a lazy line 43 secured to the crown of the main parachute, the stabilizing parachute being housed in the compartment 23 and the main parachute in the compartment 24. The main lift webs 26 of the harness are provided with releasable attachments 27 for two straps 28 secured to the lines of the stabilizing parachute 44 and to the lazy line 43, the attachments 27 being controlled by rip cords 29 operated by a barometric device 25, and is housed in the compartment 24. The locking pins 18 may be released by a static line 33 secured either to an ejection seat or the aircraft or by a manually operated release 34 and the static line 33 is connected also to barometric device 25. In operation when the aviator leaves the aircraft, the static line 33 will withdraw pins 18 to free flap 15 to release the stabilizing parachute from compartment 23 and at the same time will arm device 25, which at a pre‐determined altitude will free attachments 27 to enable the parachute 44 to run free and tension line 43 to free loops 21 and withdraw the main parachute 48. A drogue parachute 46 is attached to stabilizing parachute 44.
Rafael Wittek, Marijtje A.J van Duijn and Tom A.B Snijders
In a study of conflict in organizations, Lindenberg’s relational signaling theory is used to develop hypotheses on the impact of relationship strength, network embeddedness, and…
Abstract
In a study of conflict in organizations, Lindenberg’s relational signaling theory is used to develop hypotheses on the impact of relationship strength, network embeddedness, and organizational change on social escalation. Social escalation is defined as the involvement of one or more third parties in a conflict. An empirical test is conducted with data on 67 conflicts involving 22 managers, gathered during three years of ethnographic fieldwork and a longitudinal network study in a management team of a German paper factory. Multilevel analysis indicates that strong ties between conflicting parties decrease the level of social escalation, whereas informal power advantage of one party increases the chances for social escalation. Both effects disappear over time. It is argued that the dissolving impact of relationships and networks is due to the disappearance of so-called solidarity frame-stabilizing activities in the firm. The results highlight the context-dependence of network effects and escalation processes.
Per Johan Carlborg, Nina Hasche and Johan Kask
The purpose of this paper is to extend the knowledge on business model transformation (BMT) by developing an integrative framework for BMT dilemmas, including strategies for…
Abstract
Purpose
The purpose of this paper is to extend the knowledge on business model transformation (BMT) by developing an integrative framework for BMT dilemmas, including strategies for shaping and stabilizing market structures.
Design/methodology/approach
The study uses a case-based approach, with data from the Swedish electric utility industry.
Findings
The findings uncover practices related to both shaping and stabilizing market structure. The study contributes with insights for firms to overcome the BMT dilemma. Shaping strategies involve disruptive innovations while stabilizing strategies concerns incremental improvements in existing structures; by balancing these efforts, firms can find ways toward successful BMT.
Originality/value
With a focus on incumbent firms and the balancing act of BMT in a network, the study covers areas that have scarcely been addressed in the existing literature. Even though most business model literature has focused on shaping consumer markets, the need to consider BMT as a dual-directional process in an industrial context is emphasized in this study.
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W. Stanly and R. Vasanthakumari
The purpose of this paper is used to study the combined effect of solute gradient and magnetic field on dusty couple-stress fluid in the presence of rotation through a porous…
Abstract
Purpose
The purpose of this paper is used to study the combined effect of solute gradient and magnetic field on dusty couple-stress fluid in the presence of rotation through a porous medium.
Design/methodology/approach
The perturbation technique (experimental method) is applied in this study.
Findings
For the case of stationary convection, solute gradient and rotation have stabilizing effect, whereas destabilizing effect is found in dust particles in the system. Couple stress and medium permeability both have dual character to its stabilizing effect in the absence of magnetic field and rotation. Magnetic field succeeded in establishing a stabilizing effect in the absence of rotation.
Originality/value
The results are discussed by allowing one variable to vary and keeping other variables constant, as well as by drawing graphs.
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Pavel Pakshin and Sergey Soloviev
The purpose of this paper is to provide a parametric description (parametrization) of all static output feedback stabilizing controllers for linear stochastic discrete‐time…
Abstract
Purpose
The purpose of this paper is to provide a parametric description (parametrization) of all static output feedback stabilizing controllers for linear stochastic discrete‐time systems with Markovian switching, applications of this result to simultaneous and robust stabilization problems and obtaining of algorithms for computing stabilizing gains.
Design/methodology/approach
The proposed approach presents parameterization in terms of coupled linear matrix equations and quadratic matrix inequalities which depend on parameter matrices similar to weight matrices in linear quadratic regulator (LQR) theory. To avoid implementation problems, a convex approximation technique is used and linear matrix inequalities (LMI)‐based algorithms are obtained for computing of stabilizing gain.
Findings
The algorithms obtained in this paper are non‐iterative and used computationally efficient LMI technique. Moreover, it is possible to use well‐known LQR methodology in the process of controller design.
Originality/value
As a result of this paper, a new unified approach to design of static output feedback stabilizing control is developed. This approach leads to efficient stabilizing gain computation algorithms for both stochastic systems with Markovian switching and deterministic systems with polytopic uncertainty.
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This chapter estimates a regime switching Taylor Rule for the European Central Bank (ECB) in order to investigate some potential nonlinearities in the forward-looking policy…
Abstract
This chapter estimates a regime switching Taylor Rule for the European Central Bank (ECB) in order to investigate some potential nonlinearities in the forward-looking policy reaction function within a real-time framework. In order to compare observed and predicted policy behavior, the chapter estimates Actual and Perceived regime switching Taylor Rules for the ECB. The former is based on the refi rate set by the Governing Council while the latter relies on the professional point forecasts of the refi rate performed by a large investment bank before the upcoming policy rate decision. The empirical evidence shows that the Central Bank’s main policy rate has switched between two regimes: in the first one the Taylor Principle is satisfied and the ECB stabilizes the economic outlook, while in the second regime the Central Bank cuts rates more aggressively and puts a higher emphasis on stabilizing real output growth expectations. Second, the results point out that the professional forecasters have broadly well predicted the actual policy regimes. The estimation results are also robust to using consensus forecasts of inflation and real output growth. The empirical evidence from the augmented Taylor Rules shows that the Central Bank has most likely not responded to the growth rates of M3 and the nominal effective exchange rate and the estimated regimes are robust to including these additional variables in the regressions. Finally, after the bankruptcy of Lehman Brothers the policy rate has switched to a crisis regime as the ECB has focused on preventing a further decline in economic activity and on securing the stability of the financial system.
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Kamila Cábová, Marsel Garifullin, Ashkan Shoushtarian Mofrad, František Wald, Kristo Mela and Yvonne Ciupack
Sandwich construction has developed and has become an integral part of lightweight construction. In the recent projects, it has been shown that by using sandwich panels as…
Abstract
Purpose
Sandwich construction has developed and has become an integral part of lightweight construction. In the recent projects, it has been shown that by using sandwich panels as stabilizing members, a considerable amount of savings of steel can be achieved for structural members at ambient temperature. These stabilizing effects may also help to achieve similar savings in case of fire.
Design/methodology/approach
The response of a sandwich single panel as well as the behaviour of the whole structure at ambient temperature and in case of fire is influenced by joints between the sandwich panels and the sub-structure. The fastenings used to fix the sandwich panels to a sub-structure may be loaded by shear forces caused by self-weight, live loads or diaphragm action. Therefore, an experimental investigation was conducted to investigate the shear behaviour of sandwich panel joints in fire.
Findings
This paper summarized briefly the experimental results, numerical simulations and analytical models on the shear behaviour of sandwich panel joints at ambient and elevated temperatures.
Research limitations/implications
The work is limited to studied types of screws and sandwich panels which are generally used in current sandwich construction.
Practical implications
These stabilizing effects in sandwich construction help to achieve savings in case of fire.
Social implications
Sandwich construction has developed and has become an integral part of lightweight construction. In the recent projects, it has been shown that by using sandwich panels as stabilizing members, a considerable amount of savings of steel can be achieved for structural members at ambient temperature. These stabilizing effects help to achieve similar savings in case of fire.
Originality/value
This paper summarized briefly the experimental results, numerical simulations and analytical models on the shear behaviour of sandwich panel joints at ambient and elevated temperatures, which were not published yet.
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Michal Sobolewski, Norbert Grzesik, Zbigniew Koruba and Michal Nowicki
Nowadays, various methods of observation from unmanned aerial vehicles (UAV) are being widely developed. There are many ways of increasing the amount of information retrieved from…
Abstract
Purpose
Nowadays, various methods of observation from unmanned aerial vehicles (UAV) are being widely developed. There are many ways of increasing the amount of information retrieved from captured material. Unfortunately, hardware solutions consume a lot of energy, which is unacceptable in UAV applications, as it can have direct impact on the observing time on UAV. Those kinds of problems have been identified during the development phase of stabilizing platform in Polish Research Space Centre in Warsaw. As a result of that fact, energy saving control methods have been implemented, which estimates quality of stabilization process for the observation-tracking device (OTD).
Design/methodology/approach
Mathematical model has been designed and validated with real-life experiments for the purpose of optimization of stabilization and control process. Two types of controlling algorithms have been implemented: linear quadratic regulator and proportional derivative method for driving the mechanism. Based on numerical simulations of the mechanical model being controlled by the mentioned driver, it was possible to define membership functions. After the process of defuzzification, the controller predicts quality of stabilization under defined environmental working conditions.
Findings
An autonomous energy saving system has been created that can be implemented in many applications, where environmental conditions may change significantly.
Practical implications
To test the proposed fuzzy controller, OTD has been chosen as an example object of application. It is a mechanical platform which houses the optical observation system. It is designed to provide the best working conditions during flight.
Originality/value
That kind of decision-making unit has never been implemented before during observations which were carried out during flying of an object. That innovative controller should bring significant energy consumption savings.
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Runping Guo, Li Cai and Weiyong Zhang
Research on new internet venture growth is lacking. The purpose of this paper is to address the gap by developing and testing a theoretical model that links venturing principles…
Abstract
Purpose
Research on new internet venture growth is lacking. The purpose of this paper is to address the gap by developing and testing a theoretical model that links venturing principles (effectuation or causation) to new internet venture growth through resource bundling (pioneering or stabilizing).
Design/methodology/approach
The proposed theoretical model is developed upon the entrepreneurship literature and resource-based view. Empirical data are collected from entrepreneurs and top executives in China via a survey. The Baron and Kenny (1986) mediation model assessment procedure is used to analyze the data.
Findings
Both effectuation and causation are positively associated with new internet venture growth. Effectuation leads to pioneering resource bundling, which in turn contributes to new internet venture growth. Causation also contributes to new internet venture growth, but through stabilizing resource bundling.
Research limitations/implications
This research helps link the theory of effectuation to resource-based theory by revealing resource bundling as the mediator between effectuation, causation, and new venture growth. Moreover, the authors provide empirical evidence of the importance of resource bundling with entrepreneurial strategic decision logics to the growth of new internet ventures in transitional economies.
Practical implications
Entrepreneurs and managers of new internet ventures should leverage both venturing principles to support growth. Internet ventures generally are creative and innovative in nature, hence favor effectuation. But it will be unwise to ignore causation, which also leads to growth.
Originality/value
This is an original empirical research guided by theories. It is a novel insight to identify the mediating effect of resource bundling. This study likely will inspire more scholarly research on the subject. It also lays a solid foundation for further inquiry such as complementarities between effectuation and causation.
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In an aeroplane having a shiftable stabilizing surface, an “elevator” hinged horizontally to the said stabilizing surface, means for swinging said elevator about said horizontal…
Abstract
In an aeroplane having a shiftable stabilizing surface, an “elevator” hinged horizontally to the said stabilizing surface, means for swinging said elevator about said horizontal hinge, and means responsive to operation of said last‐named means to swing said stabilizing surface about said horizontal hinge, said last‐named means including an electric motor, an energizing circuit for said motor, means for closing said circuit, and means movable with said stabilizing surface to open said energizing circuit.