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Article
Publication date: 21 February 2019

Liang Zhang, Changzhu Wei, Yin Diao and Naigang Cui

This paper aims to investigate the problem of on-line orbit planning and guidance for an advanced upper stage.

Abstract

Purpose

This paper aims to investigate the problem of on-line orbit planning and guidance for an advanced upper stage.

Design/methodology/approach

The double impulse optimal transfer orbit is planned by the Lambert algorithm and the improved particle swarm optimization (IPSO) method, which can reduce the total velocity increment of the transfer orbit. More specially, a simplified formula is developed to obtain the working time of the main engine for two phases of flight based on the theorem of impulse. Subsequently, the true anomalies of the start position and the end position for both two phases are planned by the Newton iterative algorithm and the Kepler equation. Finally, the first phase of flight is guided by a novel iterative guidance (NIG) law based on the true anomaly update with respect to the geometrical relationship. Also, a completely analytical powered explicit guidance (APEG) law is presented to realize orbital injection for the second phase of flight.

Findings

Simulations including Monte Carlo and three typical orbit transfer missions are carried out to demonstrate the efficiency of the proposed scheme.

Originality/value

A novel on-line orbit planning algorithm is developed based on the Lambert problem, IPSO optimization method and Newton iterative algorithm. The NIG and APEG are presented to realize the designed transfer orbit for the first and second phases of flight. Both two guidance laws achieve higher orbit injection accuracies than traditional guidance laws.

Details

Aircraft Engineering and Aerospace Technology, vol. 91 no. 4
Type: Research Article
ISSN: 1748-8842

Keywords

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Article
Publication date: 1 September 2006

Chaoyong Li, Wuxing Jing, Hui Wang and Zhiguo Qi

To study the application of three‐dimensional differential geometric (DG) guidance commands to a realistic missile defense engagement, and the application of the Newton's…

Abstract

Purpose

To study the application of three‐dimensional differential geometric (DG) guidance commands to a realistic missile defense engagement, and the application of the Newton's iterative algorithm to DG guidance problems.

Design/methodology/approach

The classical differential geometry theory is introduced firstly to transform all the variables in DG guidance commands from an arc length system to the time domain. Then, an algorithm for the angle‐of‐attack and the sideslip angle is developed by assuming the guidance curvature command and guidance torsion command equal to its corresponding value of current trajectory. Furthermore, Newton's iteration is utilized to develop iterative solution of the stated algorithm and the two‐dimensional DG guidance system so as to facilitate easy computation of the angle‐of‐attack and the sideslip angle, which are formulated to satisfy the DG guidance law.

Findings

DG guidance law is viable and effective in the realistic missile defense engagement, and it is shown to be a generalization of gain‐varying proportional navigation (PN) guidance law and performs better than the classical PN guidance law in the case of intercepting a maneuvering target. Moreover, Newton's iterative algorithm has sufficient accuracy for DG guidance problem.

Originality/value

Provides further study on DG guidance problem associated with its iterative solution.

Details

Aircraft Engineering and Aerospace Technology, vol. 78 no. 5
Type: Research Article
ISSN: 0002-2667

Keywords

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Article
Publication date: 30 January 2007

Chaoyong Li, Wuxing Jing, Hui Wang and Zhiguo Qi

The paper aims to provide further study on the development and analysis of flight control system for two‐dimensional (2D) differential geometric (DG) guidance and control…

Abstract

Purpose

The paper aims to provide further study on the development and analysis of flight control system for two‐dimensional (2D) differential geometric (DG) guidance and control system based on the application of a set‐point weighting proportional‐integral‐derivative (PID) controller.

Design/methodology/approach

The commanded angle‐of‐attack is developed in the time domain using the classical differential geometry theory. Then, a set‐point weighting PID controller is introduced to develop a flight control system so as to form the 2D DG guidance and control system, and the gains of the PID controller are determined by the Ziegler‐Nichols method as well as the Routh‐Hurwitz stability criterion. Finally, the classical frequency method is utilized to study the relative stability and robustness of the designed flight control system.

Findings

The results demonstrate that the designed controller yields a fast responding and stable system which is robust to the high frequency parameters variation. Moreover, the DG guidance law is viable and effective in a realistic missile defense engagement.

Originality/value

This paper provides a novel approach on the development of DG guidance and control system associated with its stability analysis.

Details

Aircraft Engineering and Aerospace Technology, vol. 79 no. 1
Type: Research Article
ISSN: 0002-2667

Keywords

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Article
Publication date: 27 September 2018

Jian Hu, Naigang Cui, Yuliang Bai and Yunhai Geng

The purpose of this paper is to present a novel guidance law that is able to control the impact time while the seeker’s field of view (FOV) is constrained.

Abstract

Purpose

The purpose of this paper is to present a novel guidance law that is able to control the impact time while the seeker’s field of view (FOV) is constrained.

Design/methodology/approach

The new guidance law is derived from the framework of Lyapunov stability theory to ensure interception at the desired impact time. A time-varying guidance gain scheme is proposed based on the analysis of the convergence time of impact time error, where finite-time stability theory is used. The circular trajectory assumption is adopted for the derivation of accurate analytical estimation of time-to-go. The seeker’s FOV constraint, along with missile acceleration constraint, is considered during guidance law design, and a switching strategy to satisfy it is designed.

Findings

The proposed guidance law can drive missile to intercept stationary target at the desired impact time, as well as satisfies seeker’s FOV and missile acceleration constraints during engagement. Simulation results show that the proposed guidance law could provide robustness against different engagement scenarios and autopilot lag.

Practical implications

The presented guidance law lays a foundation for using cooperative strategies, such as simultaneous attack.

Originality/value

This paper presents further study on the impact time control problem considering the seeker’s FOV constraint, which conforms better to reality.

Details

Aircraft Engineering and Aerospace Technology, vol. 91 no. 1
Type: Research Article
ISSN: 1748-8842

Keywords

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Article
Publication date: 6 June 2016

John F. Riggs, Scott Widmier and Richard E. Plank

The purpose of this research is to develop a taxonomy of the impact of sales process regulations, guidance statements and laws (henceforth, referred to as “regulations”…

Abstract

Purpose

The purpose of this research is to develop a taxonomy of the impact of sales process regulations, guidance statements and laws (henceforth, referred to as “regulations”) on sales behaviours within the pharmaceutical industry, particularly as it relates to those within the USA.

Design/methodology/approach

Given the large number of regulations, guidance statements and laws and sales behaviours that comprise the domain of this study, this research uses a “multicenter, parallel-arm clinical trial data gathering method”. This approach aggregated or “stacked” the responses from three individual questionnaires; 7,493 total observations generated by 381 respondents were analyzed.

Findings

The analysis produced a six-cluster solution of regulations, guidance statements and laws indicating distinct taxonomic structures of items that affect selling activities.

Research limitations/implications

The research was conducted with a single firm in the USA. Therefore, results may not be applicable to other geographical areas, firms and industries.

Practical Implications

The knowledge of which behaviours are perceived by the salespeople to be impacted by what regulations, guidance statements and laws provides managers with a useful tool to sort their own companies’ regulations on the basis of the classification scheme.

Originality/value

This paper provides a novel taxonomic approach to organize sales activities affected by regulations, guidance statements and laws which provides a look at the unintended consequences of the item not compliance. Additionally, it uses a research methodology relatively unknown to social science inquiry.

Details

International Journal of Pharmaceutical and Healthcare Marketing, vol. 10 no. 2
Type: Research Article
ISSN: 1750-6123

Keywords

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Article
Publication date: 7 September 2015

Hao Zhou, Tawfiqur Rahman and Wanchun Chen

– The purpose of this paper is to present a novel guidance law for hypervelocity descent to a stationary target such that the impact angle and impact velocity can be constrained.

Abstract

Purpose

The purpose of this paper is to present a novel guidance law for hypervelocity descent to a stationary target such that the impact angle and impact velocity can be constrained.

Design/methodology/approach

The proposed method is based on inverse dynamics and is designed using a third-order Bézier curve approximation to the reference trajectory.

Findings

Simulations indicate that the proposed law is able to satisfy impact angle and impact velocity constraints as well as follow control and path limitations in the case of guidance under perturbations. Comparisons with other methods also indicate better performance.

Research limitations/implications

The onboard implementation requires an offline selection of Bézier parameters.

Practical implications

The presented scheme could be extremely important for further research on automated onboard control of impact angle and velocity for both re-entry and terminal guidance laws.

Originality/value

This paper presents an innovative method for the solution of an inverse dynamics-based guidance law using Bézier curve approximation.

Details

Aircraft Engineering and Aerospace Technology: An International Journal, vol. 87 no. 5
Type: Research Article
ISSN: 0002-2667

Keywords

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Article
Publication date: 13 April 2015

Stephen Mezias and Mohamad Fakhreddin

Over the last 15 years, articles about the base of the pyramid (BOP) have begun to appear in scholarly business journals. Although attention was driven initially by claims…

Abstract

Purpose

Over the last 15 years, articles about the base of the pyramid (BOP) have begun to appear in scholarly business journals. Although attention was driven initially by claims that corporations could earn a fortune selling to these consumers, it became clear that this is difficult. The paper aims to discuss these issues.

Design/methodology/approach

To move beyond this difficulty, the authors emphasize the iterative boundary capabilities built by local, for profit enterprises as the key to creating markets at the BOP.

Findings

The authors argue that the evolution of the business models to permit firms to earn profits and have positive social impact requires building iterative boundary capabilities and support this claim by reviewing two cases of community based non-profits.

Research limitations/implications

Future research should demonstrate that the process the authors observed in these two cases applies in other contexts. Scaling social impact will require sharing knowledge about iterative boundary capabilities and developing best practices that can help effective allocation of patient capital to share best practice and guide public policy.

Practical implications

Social entrepreneurs can conceptualize their own enterprises in terms of iterative boundary capabilities. Social investors can use the framework to assess and advise enterprises in which they may or have invested. Policy makers can enact laws and other legal actions to facilitate the formation of iterative boundary capabilities.

Social implications

The authors see the framework as part of a broader move toward business models that pursue both positive social impact and profits.

Originality/value

The authors link a structuring approach with an institutional perspective to enhance business models that pursue profit and create positive social impact in BOP communities.

Details

Journal of Entrepreneurship and Public Policy, vol. 4 no. 1
Type: Research Article
ISSN: 2045-2101

Keywords

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Article
Publication date: 1 March 1995

JOHN HOLLAND

This paper, which is published in two parts, is concerned with ‘behind the scenes’ self‐regulation by companies and financial institutions (FIs) relative to the…

Abstract

This paper, which is published in two parts, is concerned with ‘behind the scenes’ self‐regulation by companies and financial institutions (FIs) relative to the ‘Dissemination of price sensitive information’ guidelines outlined in the Stock Exchange report of February 1994. This paper, therefore, investigates a private form of self‐regulation outside the more public form of self‐regulation overseen by the Securities and Investments Board (SIB). The common focal points for these private self‐regulation processes are close cooperative relationships between FIs and a large portion of their portfolio companies. In Part I of this paper these relationships are employed as a common base around which to illustrate self‐regulatory processes at the level of individual companies. Part II looks at self‐regulation by UK FIs and the connections between the legal, self‐regulatory and social control mechanisms are explored and new directions for research and regulation proposed. The second part of this paper will be published in the next issue of Journal of Financial Regulation and Compliance.

Details

Journal of Financial Regulation and Compliance, vol. 3 no. 3
Type: Research Article
ISSN: 1358-1988

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Book part
Publication date: 6 December 2018

James Giordano and Kathinka Evers

Extant and newly developing techniques and technologies generated by research in brain sciences are characteristically employed in clinical medicine. However, the…

Abstract

Extant and newly developing techniques and technologies generated by research in brain sciences are characteristically employed in clinical medicine. However, the increasing capabilities conferred by these approaches to access, assess and affect cognition, emotion and behavior render them viable and attractive for engagement beyond the clinical realm, in what are referred to as “dual-use” applications. Definitions of what constitutes dual-use research and applications can vary so as to include utilization in the public sector for lifestyle or wellness purposes – with growing participation of a do-it-yourself (i.e., biohacking) community, and an iterative interest and use in military and warfare operations. Such uses can pose risks to public safety, and challenge research ethics’ principled imperative for non-harm (although while complete avoidance of any harm may be in reality impossible, certainly any/all harms incurred should be minimized). Thus, it is important to both clarify the construct of dual-use brain research and address the ethical issues that such research fosters. This chapter provides a review and clarification of the concept of dual-use brain science, and describes how current and emerging tools and techniques of brain research are actually or potentially employed in settings that threaten public health and incur ethical concerns. Key ethical issues are addressed, and recommendations for ethical guidance of potentially dual-use research are proposed.

Details

Ethics and Integrity in Health and Life Sciences Research
Type: Book
ISBN: 978-1-78743-572-8

Keywords

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Article
Publication date: 20 June 2016

Jean Mary Daly Lynn, Elaine Armstrong and Suzanne Martin

The purpose of this paper is to outline the application of user centred design (UCD) within a research project to support the design, development and evaluation of a brain…

Abstract

Purpose

The purpose of this paper is to outline the application of user centred design (UCD) within a research project to support the design, development and evaluation of a brain computer interface (BCI) with associated home-based services and remote therapy station for people with acquired brain injury (ABI).

Design/methodology/approach

A multi- stakeholder UCD approach was adopted to include people living with ABI, their caregivers and therapists providing rehabilitation. A three-phased iterative approach was implemented: Phase 1 was to gather user requirements, Phase 2 an iterative design phase with end user (EU) groups and therapists and finally the verification and implementation phase. The final phase had two strands of a home-based BCI evaluation with target EUs and their caregivers, alongside this, therapists evaluated the final therapist station that supports the use of the BCI at home. Ethical governance, inline with Ulster University, was awarded.

Findings

UCD enabled the co-creation and validation of a home-based BCI system for social inclusion and rehabilitation.

Originality/value

This was the first BCI project to adopt UCD to design and validation a novel home-based BCI system and migrate this from the lab to home. It highlights the importance of UCD to bridge the gap between the technical developers and those whom the technology is aimed at. This complex design process is essential to increase usability and reduce device abandonment.

Details

Journal of Assistive Technologies, vol. 10 no. 2
Type: Research Article
ISSN: 1754-9450

Keywords

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