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1 – 10 of 701Nai-ming Qi, Qilong Sun and Yong Yang
The purpose of this paper is to study the effect of J3 perturbation of the Earth’s oblateness on satellite orbit compared with J2 perturbation.
Abstract
Purpose
The purpose of this paper is to study the effect of J3 perturbation of the Earth’s oblateness on satellite orbit compared with J2 perturbation.
Design/methodology/approach
Based on the parametric variation method in the time domain, considering more accurate Earth potential function by considering J3-perturbation effect, the perturbation equations about satellite’s six orbital elements (including semi-major axis, orbit inclination, right ascension of the ascending node, true anomaly, eccentricity and argument of perigee) has been deduced theoretically. The disturbance effects of J2 and J3 perturbations on the satellite orbit with different orbit inclinations have been studied numerically.
Findings
With the inclination increasing, the maximum of the semi-major axis increases weakly. The difference of inclination disturbed by the J2 and J3 perturbation is relative to orbit inclinations. J3 perturbation has weak effect on the right ascension and argument of perigee. The critical angle of the right ascension and argument of perigee which decides the precession direction is 90° and 63.43°, respectively. The disturbance effects of J2 and J3 perturbations on the argument of perigee, right ascension and eccentricity are weakened when the eccentricity increases, simultaneously, the difference of J2 and J3 perturbations on argument of perigee, right ascension and argument of perigee decreases with eccentricity increasing, respectively.
Practical implications
In the future, satellites need to orbit the Earth much more precisely for a long period. The J3 perturbation effect and the weight compared to J2 perturbation in LEO can provide a theoretical reference for researchers who want to improve the control accuracy of satellite. On the other hand, the theoretical analysis and simulation results can help people to design the satellite orbit to avoid or diminish the disturbance effect of the Earth’s oblateness.
Originality/value
The J3 perturbation equations of satellite orbit elements are deduced theoretically by using parametric variation method in this paper. Additionally, the comparison studies of J2 perturbation and J3 perturbation of the Earth’s oblateness on the satellite orbit with different initial conditions are presented.
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Bill Brinkmann and Dan O'Brien
Ascension Health has developed a leadership formation program and decision‐making process specifically designed to tap into the inner spiritual strengths of its religiously…
Abstract
Purpose
Ascension Health has developed a leadership formation program and decision‐making process specifically designed to tap into the inner spiritual strengths of its religiously pluralistic workforce in order to foster leadership that is more effective in initiating organizational cultural changes necessary for making successful quality improvements vital for the transformation of healthcare. This paper aims to focus on this initiative.
Design/methodology/approach
The paper is a case study, describing how Ascension Health designed a quantified measurement tool used to test the degree to which key characteristics of its mission, vision and values are implemented in its policies, practices and outcomes. Applying principles of decision‐making theory from Lonergan, Harrison and Nutt, Ascension Health also created an organizational discernment process designed to habitualize best practices of decision making that support the organization's mission and transformational goals.
Findings
The authors describe how their organization's interventions have strengthened the practical wisdom of its leaders, helping it to improve on its faith‐based mission and transformational goals. Case examples are included to illustrate the transformational effects of these interventions.
Practical implications
Applying formation practices that engage a spiritually diverse workforce and adopting disciplined processes of decision making can be adapted to any complex organization willing to dedicate itself to the inner transformation, participation and empowerment of its leaders and associates.
Originality/value
The formation program, decision‐making approach and measurement tool are all original. Business leaders and leadership development programs will find the experience of Ascension Health to be a valuable reference for their own organizational change initiatives.
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This study examines the effects of foreign branch activity on commercial banks in the Central, Eastern, and Southeastern European countries for the period 1995–2015. The author…
Abstract
This study examines the effects of foreign branch activity on commercial banks in the Central, Eastern, and Southeastern European countries for the period 1995–2015. The author shows that more foreign bank branches are present in countries that have higher taxes and regulatory restrictions on bank activity. The increased activity of foreign bank branches adversely affects lending by foreign banks, and to a lesser extent, that of state-owned banks. The author attributes this finding to the fact that foreign bank branches and foreign banks compete for the same type of clients, namely, multinational corporations.
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Accounting research has mirrored the annual report in its eclecticism. There remain, however, notable gaps in the research profile, including theological perspectives and the…
Abstract
Accounting research has mirrored the annual report in its eclecticism. There remain, however, notable gaps in the research profile, including theological perspectives and the analysis of visual images. The contribution of this present study is twofold: to advance a general philosophical reading of sacred vestiges within financial reporting, and to add to the interpretation of visual images within financial reporting. The examination takes as its primary guide the philosopher and religious historian, Mircea Eliade, and also draws on the work of C.G. Jung. The paper first suggests that archaic traces of a sacred concept of cyclical and repeatable time may be perceived in the periodic preparation of financial statements and associated ritual. It is further contended that the visual space of financial reporting may bear traces of archaic religious attitudes; specific images are analysed and illuminated by religious and cultural associations with ascension.
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Oana Cătălina Iederan, Petru Lucian Curşeu, Patrick A.M. Vermeulen and Jac L.A. Geurts
The purpose of this paper is to examine the cognitive factors explaining how exogenous institutional change (IC) impacts on organizational actions.
Abstract
Purpose
The purpose of this paper is to examine the cognitive factors explaining how exogenous institutional change (IC) impacts on organizational actions.
Design/methodology/approach
The authors interviewed 121 Romanian entrepreneurs, 69 before and 52 after Romania's ascension to the EU and used cognitive mapping to elicit their cognitive schemas about this macro‐IC. Similarities and differences between cognitive structures are explored and the aggregated cognitive maps before and after the IC are created, in order to understand how managerial cognition changed following IC.
Findings
The results show that the richness of the cognitive schemas before the IC is lower than after the IC took place. Furthermore, the entrepreneurs who framed the IC as a threat adopted isomorphic actions and reported less positive organizational outcomes as compared to the entrepreneurs that represented the IC as an opportunity.
Research limitations/implications
The research described is exploratory in nature and opens new interesting research directions in the cognitive pillar of institutional theory. Moreover, a cognitive mapping technique is used to elicit and represent managerial cognition and in this way adds to the methods used in institutional research.
Practical implications
The results presented in this paper help policy makers to understand that the impact of exogenous IC on organizational actions is not direct, but mediated by the cognitive representations developed by strategic decision makers.
Originality/value
The paper integrates institutional theory with the work on cognition and explores how cognitive representations affect the relation between environmental pressures and organizational responses.
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Abstract
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María Ascensión Molina Huertas, Francisco J. Del Campo Gomis, David Bernardo López Lluch and Asunción María Agulló Torres
The aim of this article is to analyse the opinions (and the differences among them) of golf players, golf courses managers and the general population about the economic and social…
Abstract
The aim of this article is to analyse the opinions (and the differences among them) of golf players, golf courses managers and the general population about the economic and social impact of golf courses in a tourist destination (Alicante province, in Spain) from the data collected in three surveys. Golf players and golf courses managers have a more positive opinion about this economic and social impact than the population in the province. This is due to the knowledge of the first group about golf industry benefits. Therefore, communication about these social and economic benefits of golf courses has to be increased with the population in the area in order to improve their opinion about them.
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Looks at changes in the human‐computer interface, particularly in the field of using computers for applications which require an accurate registration from an input device in “six…
Abstract
Looks at changes in the human‐computer interface, particularly in the field of using computers for applications which require an accurate registration from an input device in “six degrees of freedom”, including robotics, CAD, anthropometric/biomechanic analysis, military, digital antique cataloguing and archaeological site surveys.
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The purpose of this paper is to design free return trajectories launching at lower-latitude launch site Wenchang and landing at relatively high-latitude landing site Siziwang…
Abstract
Purpose
The purpose of this paper is to design free return trajectories launching at lower-latitude launch site Wenchang and landing at relatively high-latitude landing site Siziwang Banner tailored to human lunar missions for China, and in general demonstrate the feasibility of high-latitude landings with acceptable entry range.
Design/methodology/approach
Free return trajectories satisfying all basic constraints were generated directly by a high-fidelity model with multiple differential corrections. Suitable initial assumptions, control parameters, constraints and stopping conditions were set. Method was developed to automatically converge unlimited trajectories accurately to the same constraints, and their characteristics affected by the ephemeris were analyzed.
Findings
Launching into lower Earth inclination plus high-latitude landing with acceptable entry range requires asymmetric trajectories with high inclination Earth entry only from the south. Periodic trends of parameters at launch, injection and entry were found and analyzed. Nominal trajectory covering phases from launch to landing for China human moon flight with minimum entry range were designed.
Practical implications
Such trajectories can be used by China’s future manned lunar missions. Spacecraft capability and ground station distribution shall adjust accordingly.
Originality/value
Previous studies mainly concentrated on symmetric free returns using low-fidelity models first. This paper investigates asymmetric free returns skipping simplified gravity model approximation to simultaneously achieve high-latitude landing and acceptable entry range, and accurate automated generation of feasible trajectories daily across 19-year lunar nodal cycle within every monthly launch window without trial and error to reflect the actual effect by the ephemeris only. Others include landing accurately by controlling entry direction and range (and altitude), minimizing entry range and designing an effective scheme of differential correction for full convergence.
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