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X-ray pulsar navigation (XPNAV) is an autonomous celestial navigation technology for deep space missions. The error in the pulse time of arrival used in pulsar navigation is large for various practical reasons and thus greatly reduces the navigation accuracy of spacecraft near the Earth and in deep space. This paper aims to propose a novel method based on ranging information that improves the performance of XPNAV.

This method replaces one pulsar observation with a satellite observation. The ranging information is the difference between the absolute distance of the satellite relative to the spacecraft and the estimated distance of the satellite relative to the spacecraft. The proposed method improves the accuracy of XPNAV by combining the ranging information with the observation data of two pulsars.

The simulation results show that the proposed method greatly improves the XPNAV accuracy by 70% compared with the conventional navigation method that combines the observations of three pulsars. This research also shows that a larger angle between the orbital plane of the satellite and that of the spacecraft provides higher navigation accuracy. In addition, a greater orbital altitude difference implies higher navigation accuracy. The position error and ranging error of the satellite have approximately linear relationships with the navigation accuracy.

The novelty of this study is that the satellite ranging information is integrated into the pulsar navigation by using mathematical geometry.

This study aims to address the problem of the divergence of traditional inertial navigation system (INS)/celestial navigation system (CNS)-integrated navigation for ballistic missiles. The authors introduce Doppler navigation system (DNS) and X-ray pulsar navigation (XNAV) to the traditional INS/CNS-integrated navigation system and then propose an INS/CNS/DNS/XNAV deep integrated navigation system.

DNS and XNAV can provide velocity and position information, respectively. In addition to providing velocity information directly, DNS suppresses the impact of the Doppler effect on pulsar time of arrival (TOA). A pulsar TOA with drift bias is observed during the short navigation process. To solve this problem, the pulsar TOA drift bias model is established. And the parameters of the navigation filter are optimised based on this model.

The experimental results show that the INS/CNS/DNS/XNAV deep integrated navigation can suppress the drift of the accelerometer to a certain extent to improve the precision of position and velocity determination. In addition, this integrated navigation method can reduce the required accuracy of inertial navigation, thereby reducing the cost of missile manufacturing and realising low-cost and high-precision navigation.

The velocity information provided by the DNS can suppress the pulsar TOA drift, thereby improving the positioning accuracy of the XNAV. This reflects the “deep” integration of these two navigation methods.

The authors proposed a new method of fast time delay measurement for integrated pulsar pulse profiles in X-ray pulsar-based navigation (XNAV). As a basic observation of exact orientation in XNAV, time of arrival (TOA) can be obtained by time delay measurement of integrated pulsar pulse profiles. Therefore, the main purpose of the paper is to establish a method with fast time delay measurement on the condition of limited spacecraft’s computing resources.

Given that the third-order cumulants can suppress the Gaussian noise and reduce calculation to achieve precise and fast positioning in XNAV, the proposed method sets the third-order auto-cumulants of standard pulse profile, the third-order cross-cumulants of the standard and the observed pulse profile as basic variables and uses the cross-correlation function of these two variables to estimate the time delay of integrated pulsar pulse profiles.

The proposed method is simple, fast and has high accuracy in time delay measurement for integrated pulsar pulse profiles. The result shows that compared to the bispectrum algorithm, the method improves the precision of the time delay measurement and reduced the computation time significantly as well.

To improve the performance of time delay estimation in XNAV systems, the authors proposed a novel method for XNAV to achieve precise and fast positioning.

Compared to the bispectrum algorithm, the proposed method can improve the speed and precision of the TOA’s calculation effectively by using the cross-correlation function of integrated pulsar pulse profile’s third-order cumulants instead of Fourier transform in bispectrum algorithm.

Within New Zealand, cultural festivals play a vital role in the local representation of diasporic cultures. By analysing the production design of festivals, in Auckland, New Zealand representing Indian culture between 1995 and 2015, the purpose of this paper is to create a deeper understanding of collaborative networks and power relationships. Using Richard’s pulsar/iterative network theory and Booth’s notion of cultural production networks, a new theoretical model is proposed to visually track the collaborative networks that sustain and bridge cultures, empower communities and fulfil political agendas.

This ethnographic research draws upon event management studies, industry practice, ethnomusicology and sociology to take a multi-disciplinary approach to an applied research project. Using Richards’ pulsar and iterative event framework Castells’ network theory, combined with qualitative data, this research considers critical collaborative relationships clusters and how they might impact on the temporal nature of festivals.

The 1997 Festival of Asia and the subsequent Lantern Festival in 2000 and Diwali: Festival of Lights in 2002 were pulsar events that played a significant role in collaborative networks that expand across cultures, countries and traditions. The subsequent iterative events have played a vital role in the representation of Asian cultural identity in general and, more specifically, representing of the city’s growing – in both size and cultural diversity – Indian diaspora.

This research proposes a new conceptual model on festival management and diasporic communities in the Asia-Pacific region. Richards’ and Booth’s conceptual models are used, as a starting point, to offer a new way of considering the importance of looking at collaborative relationships through historical perspectives. The framework explored contributes a new approach to cultural festival network theory and a means to understand the complexity of networks required that engage actors from inside and outside both local and global communities.

The purpose of this article is to contribute to a dialogue between practitioners and academics. The article discusses the relevance of Public Sector Accounting (PSA) reforms, including their key approaches and challenges, and the role of the World Bank's Public Sector Accounting and Reporting (PULSAR) Program.

This is a practitioner's viewpoint, which reflects World Bank and PULSAR Program's publicly available documents and the opinions of a practitioner involved in the implementation of PSA reforms.

Implementation of PSA reforms, based on the good international standards and practices, such as International Public Sector Accounting Standards (IPSAS), represents an opportunity for governments to significantly improve (1) the quality, reliability and comparability of their financial information; (2) decision-making process of the high-level public officials; and (3) the overall levels of fiscal transparency and public sector accountability and performance. There are several main approaches of the PSA reform implementation that could be observed across the globe. In practice, many countries and different jurisdictions face multiple challenges associated with PSA reform implementation. The World Bank and PULSAR Program in particular represent a valuable source of knowledge generation and sharing, and also acts as a catalyst for promoting PSA reforms in beneficiary countries.

The limitations of this article (which are also its strength in terms of fitness for purpose) are that as a practitioner's viewpoint, it provides a brief overview and personal judgements rather than an empirical analysis of developments applying a theoretical framework.

A practitioner's engagement with academic supports increased understanding of the respective views leading to better outcomes for practitioners and academics working in the area of public sector accounting.

The article provides a practitioner's input on the relevance of PSA reforms and their key challenges.

World renowned as manufacturers of ejection seats and ancillary equipment for all manner of military aircraft, Martin Baker (Engineering) Ltd. has recently made a substantial investment in advanced CNC machine tools at its Higher Denham, Bucks, factory. To support these machines, two Pulsar computer aided programming systems have been installed.

The purpose of this paper is to complement organizational diffusion research by illustrating influence of factors specific to collective adoption process, which has received limited focus in diffusion research. The research question is how do different actors perceive attributes of innovation and how does that influence the process towards initial adoption of a new technology?

Owing to limited prior research and need to assess multiple innovation variables, the paper employs an inductive case study. Uses Rogers' five main perceived attributes of innovation as an analysis framework and functional actors as a unit of analysis. Two cases with early stage companies commercialising new, differentiating technologies to global, established value networks. Key actors influencing the adoption of the technologies interviewed.

The paper illustrates how actor characteristics and perceptions of innovation attributes are interrelated; perceptions of different functional actors on innovation attributes differ, both gating and advancing the adoption process for innovations; and the actors' differing perceptions and the resulting interaction influence the duration and outcome of adoption process.

Non‐traditional methodology in diffusion research leading to larger interpretation of the findings, but enabling assessment of multiple variables and their interrelations not captured with traditional approaches. Areas for further research: generalizable patterns in interrelation between actors' functional roles and perceptions of innovation attributes as well as evolution of perceptions during collective adoption process.

Innovation providers need to identify both the parties gating and advancing the innovation as well as their underlying motivations. They need to ensure sufficient interaction between themselves and the actors and among the actors to leverage the positive momentum to overcome the resistance towards innovation.

The paper addresses the organizational diffusion research critique of, e.g. Frambach, of Damanpour, and of Wejnert on insufficient attention being paid to actor level characteristics and their influence on diffusion as well as interaction of different variables. The paper empirically illustrates how factors specific to collective adoption influence the process towards adoption.

Rather than organize as traditional firms, many of today’s companies organize as platforms that sit at the nexus of multiple exchange and production relationships. This chapter considers a most basic question of organization in platform contexts: the choice of boundaries. Herein, I investigate how classical economic theories of firm boundaries apply to platform-based organization and empirically study how executives made boundary choices in response to changing market and technical challenges in the early mobile computing industry (the predecessor to today’s smartphones). Rather than a strict or unavoidable tradeoff between “openness-versus-control,” most successful platform owners chose their boundaries in a way to simultaneously open-up to outside developers while maintaining coordination across the entire system.

Mental health recovery across cultures lacks understanding and suitable measures. The Questionnaire about the Process of Recovery (QPR) is a self-report instrument measuring personal recovery outcomes for consumers of mental health services. However, the extent of its relevance among culturally and linguistically diverse (CALD) communities is unclear. This pilot study aimed to examine the relevance and utility of the QPR among CALD consumers of primary mental health services in Australia.

Eleven individual, semi-structured interviews were conducted with two general practitioners (GPs) and nine consumers from two clinics, at locations with high Iranian and Burmese refugee or asylum seeker populations. Interviews were transcribed and analysed using a thematic framework approach.

Although almost all consumers had little or no understanding of the concept of personal recovery, they found the QPR culturally acceptable and understandable. Using the QPR during mental health consultations can help with needs identification and goal setting. Challenges in using the QPR included completion time, cross-cultural differences in concepts and norms for some items, and need for careful translation. Consumers suggested additional items regarding family reputation, sexuality, and spirituality.

The QPR is potentially a valuable tool to support mental health consultations with CALD consumers, from the perspectives of both GPs and consumers.