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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

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Book part
Publication date: 8 October 2018

David Brennan and M. Elizabeth Davidson

While the important role of information literacy instruction as a central service in academic libraries is well observed in scholarly literature, there has been little…

Abstract

While the important role of information literacy instruction as a central service in academic libraries is well observed in scholarly literature, there has been little examination of the impact of the rapid increase of instructional duties on practicing librarians, whose traditional instruction duties have expanded or whose positions have not traditionally required leading a classroom. The study in this chapter explores librarians’ perceptions of the impact that increased instruction tasks have had on their day-to-day and long-term goals, perceptions of the support they receive in performing their instructional duties, and what types of instruction training they have received throughout their career. The ways in which the addition of instruction duties for librarians have been perceived by the librarians themselves as they strive to increase support for instructional services without impacting the library’s ability to continue to perform traditional public and technical services functions is discussed as a marker of the future needs of the field and the necessity of recognizing professional strain.

Details

Challenging the “Jacks of All Trades but Masters of None” Librarian Syndrome
Type: Book
ISBN: 978-1-78756-903-4

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Article
Publication date: 5 July 2011

Halil D. Kaya

The purpose of this study is to examine the impact of interest rates on the size and the maturity choice of a syndicated bank loan. In addition, it attempts to determine…

Abstract

Purpose

The purpose of this study is to examine the impact of interest rates on the size and the maturity choice of a syndicated bank loan. In addition, it attempts to determine the long‐run impact of a syndicated loan on the borrower's capital structure.

Design/methodology/approach

The paper uses a sample of 6,903 syndicated bank loans in the USA, covering the period 1984‐2004. First, all syndicated loans are categorized into two groups: loans in periods of increasing interest rates, and loans in periods of decreasing rates. Then, non‐parametric tests are performed to compare the characteristics of the two groups, including the proceeds from the loans, and robust regressions are used to examine the impact of the interest rates on the maturity choice. Finally, robust regressions are employed to examine the long‐run impact of the interest rates on the borrowers' leverage ratios.

Findings

On the whole, the results reject the market timing theory of capital structure for syndicated bank loans. Firms in the two groups borrow in similar amounts, and in the long run, the difference between the two groups' leverage ratios is statistically insignificant. On the other hand, firms tend to choose longer maturities when the interest rates are low compared to the rates two or three years ago.

Originality/value

To the best of the author's knowledge, this is the first study that links debt market conditions to the leverage ratios of firms that borrow in the syndicated bank loan market. In other words, this is the first study that tests the market timing theory of capital structure for syndicated bank loans.

Details

Managerial Finance, vol. 37 no. 8
Type: Research Article
ISSN: 0307-4358

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Article
Publication date: 29 March 2021

Nicola J. Beatson, Paul de Lange and Heinrich Oosthuizen

Students have a finite amount of time that they can allocate between commitments of study–work–life. Striking a balance between these competing activities is an individual…

Abstract

Purpose

Students have a finite amount of time that they can allocate between commitments of study–work–life. Striking a balance between these competing activities is an individual conundrum and this study aims to explore the impact of extramural activities and paid employment on the academic performance of accounting students.

Design/methodology/approach

Guided by Carroll’s model of school learning, the authors adopt a quantitative approach where they survey (N = 264) and gather responses (n = 195) from students with respect to their choices regarding spare time outside study. These perceptions are then compared to their academic performance. Quantitative responses were subsequently triangulated with interview findings to provide in-depth analysis.

Findings

Findings provide greater understanding for educators of the student lived experience, which reveals that the work, study and life balance is individually nuanced and is largely driven by the individual’s perceived level of interference from work, which is a significant predictor of academic performance.

Originality/value

Analysis of the determinants of student learning includes prior academic achievement, confidence with numbers, critical thinking, gender and prior accounting knowledge. Yet, little is known about the implication of activities outside the formal curriculum. This study addresses this void in the literature and provides a much-needed link back to accounting faculty’s pedagogical approaches as they adapt to a cohort’s learning behaviour. This study also adds to the debate on the need for more discussion with faculty to allow alternate arrangements based on extramural activities and employment commitments. Greater understanding of study–work–life balance for students provides an opportunity for new dialog between faculty and students.

Details

Pacific Accounting Review, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0114-0582

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Article
Publication date: 12 October 2012

A.A. (Alex) Alblas and J.C. (Hans) Wortmann

In new product development (NPD), changes to the initial designs are often proposed for on‐going design projects due to new insights. These engineering changes belong to a…

Abstract

Purpose

In new product development (NPD), changes to the initial designs are often proposed for on‐going design projects due to new insights. These engineering changes belong to a wide range from incremental to radical and, in their impact, even to discontinuous change. Consequently, the actual workload of development projects confronted with engineering changes does not match the initial work estimates for the project's work packages. Accordingly, the intended timing of readiness of development projects in an NPD program will drift away. This timing is one of the causes of change propagation to other projects which results in even more engineering changes. For larger changes, the effects on timing may be disastrous. The purpose of this paper is to reveal the cause‐and‐effect relationships triggered by various types of changes and explain the need for a more integrated approach to managing engineering change.

Design/methodology/approach

A longitudinal case study was performed at a leading microlithography manufacturing company, in which almost 20,000 engineering changes were included. This study allowed the disclosure of the complexities of engineering change management and provides guidelines for handling the resulting problems arising from managing these various types of change.

Findings

In the study, various sources of complexities in managing engineering change were observed, which hinder effective implementation of various types of engineering change. Based on the case observations, a number of improvement possibilities are proposed, such as: alignment of goals and impacts of engineering change on all organizational levels; and planning, monitoring and controlling discontinuous engineering changes as separate projects.

Originality/value

Although further studies are needed to replicate the results, the paper gives a more thorough understanding of factors that could support the implementation of discontinuous innovation in incumbent firms by using the engineering change management process.

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Article
Publication date: 1 October 2011

Thomas Baker and Scott A Jones

While the goal of almost any service provider is to eliminate wait from the consumption experience, there are a number of service environments where this ideal may be…

Abstract

While the goal of almost any service provider is to eliminate wait from the consumption experience, there are a number of service environments where this ideal may be impractical, if not impossible, to deliver, among them live sport. Live sporting events often have queues at entry and exit gates, facility concessions and toilets. This study tests a model featuring antecedents not used in prior research on waiting. Findings suggest that facility layout features and waiting fill time both have a positive influence on spectators' feelings about a wait. Most interestingly perhaps, these same antecedents may also serve as a cue that long waits are likely.

Details

International Journal of Sports Marketing and Sponsorship, vol. 13 no. 1
Type: Research Article
ISSN: 1464-6668

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Book part
Publication date: 26 April 2017

Prince Boateng, Zhen Chen and Stephen O. Ogunlana

Abstract

Details

Megaproject Risk Analysis and Simulation
Type: Book
ISBN: 978-1-78635-830-1

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Article
Publication date: 14 June 2018

Katrin Wudy, Maximilian Drexler, Lydia Lanzl and Dietmar Drummer

The thermal history during laser exposure determines part properties in selective laser sintering (SLS). The purpose of this study is to introduce a new measurement…

Abstract

Purpose

The thermal history during laser exposure determines part properties in selective laser sintering (SLS). The purpose of this study is to introduce a new measurement technique based on a CO2 laser unit combined with a high-speed DCS. A first comparison of the thermal history during laser exposure measured with Laser-high-speed-(HS)-differential scanning calorimetry-(DSC) and in SLS process is shown.

Design/methodology/approach

This Laser-HS-DSC allows an imitation of the SLS-process in a very small scale, as the sample is directly heated by a CO2 laser. For this study, the laser power and the impact time is varied for determining temperature and achieved heating rates. Consequently, the temperature levels measured by the Laser-HS-DSC are compared with measurements in SLS-process.

Findings

The influence of laser power and impact time on resulting maximum temperatures und heating rates during laser exposure are investigated. With increasing laser power and impact time the maximum temperature rises up to approximately 450°C without material degradation. The heating rate increases up to an impact time of 3 ms and stays almost equal for higher durations.

Research limitations/implications

The Laser-HS-DSC experiments are based on few particles limiting a complete comparison with SLS process. In SLS, one volume element is exposed several times. In this study the PA12 material was exposed only once.

Originality/value

For the first time, laser sintering experiments can be transferred to a laboratory scale to analyze the influence of laser exposure on resulting temperature field during laser exposure without superimposing effects.

Details

Rapid Prototyping Journal, vol. 24 no. 5
Type: Research Article
ISSN: 1355-2546

Keywords

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Book part
Publication date: 1 March 2021

Miswanto Miswanto

The purpose of this study is to investigate whether equity market timing has a persistent impact on the firm’s capital structure or not. In achieving this purpose, there…

Abstract

The purpose of this study is to investigate whether equity market timing has a persistent impact on the firm’s capital structure or not. In achieving this purpose, there are two hypotheses developed in this study. The first hypothesis is that historical price-book-value (PBV) negatively affect leverage; while the second hypothesis is that historical PBV ratio negatively affects the change of cumulative on leverage. The sample of this study is cross sectional data obtained from the Indonesia Stock Exchange for 2001–2011 research period. The author disentangles the sample into subsamples based on IPO+k, in which k is the number of years after the initial public offering (IPO). The results show that most of the regression coefficients in the historical PBV do not have negative impact on the capital structure and only a small part of the regression coefficient of the historical PBV has a statistically negative impact on the capital structure. Therefore, the findings of this research conclude that equity market timing doesn’t have persistent impact on capital structure of the firms in Indonesia.

Details

Recent Developments in Asian Economics International Symposia in Economic Theory and Econometrics
Type: Book
ISBN: 978-1-83867-359-8

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Article
Publication date: 5 March 2018

Mohamed A. Youssef and Eyad M. Youssef

The purpose of this paper is to examine the impact of integrating ISO 9000 and total quality management (TQM) on operational performance of manufacturing organizations and…

Abstract

Purpose

The purpose of this paper is to examine the impact of integrating ISO 9000 and total quality management (TQM) on operational performance of manufacturing organizations and their journey toward achieving world-class manufacturing (WCM) status.

Design/methodology/approach

The authors used a conceptual model and its empirical validation based on a sample of 2,961 responses from one developing and three developed economies. Univariate and multivariate analyses were used to test five main hypotheses.

Findings

Plants that integrate ISO 9000 and TQM progressed faster toward achieving WCM status and have better operational performance in terms of quality management, inventory management, time-based performance, and competitiveness.

Research limitations/implications

The sample from the developing economy includes only 254 responses, while the one from the three developed economies includes 2,907 responses.

Practical implications

Findings of this study have many implications for both academic and practitioners. These findings encourage practitioners to consider ISO 9000 and TQM as complementary, not substitutes.

Social implications

Developing economies should follow the footsteps of developed economies in considering quality as a competitive advantage in global markets.

Originality/value

The paper addresses in a unique and unprecedented way the synergistic impact of ISO 9000 and TQM on operational performance. The study is the first in its kind to include responses from both developing and developed economies. The development of the synergy index was never addressed before.

Details

International Journal of Quality & Reliability Management, vol. 35 no. 3
Type: Research Article
ISSN: 0265-671X

Keywords

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