bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fast trajectory planning based on in‐flight waypoints for unmanned aerial vehicles
Authors: Babaei A.R. , Mortazavi M. 
Published: May 2010

PurposeThe purpose of this paper is to propose an efficient algorithm for trajectory planning of unmanned aerial vehicles (UAVs) in 2D spaces. This paper has been motivated by the challenge to develop a fast trajectory planning algorithm for autonomous UAVs through mid‐course waypoints (WPs). It is assumed that there is no prior knowledge of these WPs, and their configuration is computed as in‐flight procedure.Design/methodology/approachSince the off‐line techniques cannot be applied, it is required to apply an online trajectory planning algorithm. For this reason, based on the optimal control and the geometry, each segment of trajectory is designed with respect to a local frame. The algorithm is implemented as a real‐time manner in terms of the down‐range variable.FindingsThe proposed algorithm tries to find not only a feasible trajectory (the constraint includes the maximum heading angle rate) but also an optimal trajectory (the objective locally is to minimize the length of the path). This online trajectory planning algorithm gradually produces a smooth 2D trajectory aiming at reaching the mid‐course WPs and the final target so that they are smoothly connected with each other. The mid‐course WPs are described through the given down‐range, cross‐range, and heading angle.Originality/valueBased on geometrical principles, this algorithm is capable of re‐planning the trajectory as in‐flight manner, and the computational burden approaches the online capabilities for UAVs with high velocity.
Dynamics and control of a tri‐axis satellite attitude simulator
Authors: Shan Jinjun 
Published: May 2010

PurposeThe purpose of this paper is to develop a tri‐axis spacecraft simulator to simulate the three‐axis attitude motion of a satellite and for ground‐based hardware‐in‐the‐loop simulation.Design/methodology/approachThe structure of tri‐axis satellite attitude simulator is designed first. Full dynamic model is then derived. Based on the dynamic model, a simple proportional‐integral‐derivative controller is developed and applied to control the motion of simulator.FindingsThe effectiveness of the proposed simulator configuration has been verified through numerical simulations. The tri‐axis simulator can follow the satellite attitude motion precisely.Originality/valueThis paper is valuable for researchers working on the development of tri‐axis spacecraft attitude simulator. This work is original. The simulator configuration has been applied to a satellite mission that was launched successfully in 2006.
Preliminary design correlations for twin civil turboprops and comparison with jet aircraft
Authors: Vouvakos Xenakis , Kallinderis Yannis , Menounou Pinelopi 
Published: May 2010

PurposeThe purpose of this paper is to compare twin engine civil turboprop aircraft with their jet engine counterparts; to simplify the preliminary design process and the initial evaluation of twin civil turboprop aircraft; to include noise level consideration in the preliminary design; and to form a current database of design parameters for representative civil turboprop aircraft.Design/methodology/approachThe paper finds linear correlations between key design parameters. It compares the corresponding correlations for turboprop and jet engine aircraft.FindingsThe paper finds direct linear relationships between design parameters including noise levels; simplified preliminary design process; and differences in the sensitivity of design parameters between turboprop and jet aircraft.Research limitations/implicationsThe turboprop aircraft database needs to be expanded. Also, investigation of non‐linear relations between design parameters is a next step.Practical implicationsQuick assessment and comparisons of existing designs is an outcome. Also, the preliminary design process is simplified and expedited. Lastly, noise regulations can affect the design right from the beginning and not at a later stage.Originality/valueNew correlations which simplify the current procedures for preliminary design of twin civil turboprop aircraft. In addition, the noise is included right from the beginning of the design. Direct comparison between turboprop and jet aircraft afforded via their correlated preliminary design parameters. Finally, a database of twin turboprops is formed with specially selected aircraft that are current and cover a wide spectrum of sizes.
From inspired teaching to effective knowledge work and back again
Authors: Eschenbach Sebastian 
Published: May 2010

PurposeThe emerging knowledge societies will – besides many other dramatic changes – see a teaching revolution. This paper seeks to propose quality standards for this new type of teaching.Design/methodology/approachThe paper argues that Peter Drucker experienced much of what he later came to call the principles of self management and effective knowledge work as a boy aged nine or ten at the Schwarzwald School – an utterly exceptional, progressive elementary school in Vienna. Given these astonishing similarities, this school's avant‐garde approach to teaching might just provide some insights into what effective teaching for a future knowledge society should be like. The paper is based to a large extent on accounts by and about the almost forgotten school's owner‐manager Eugenie Schwarzwald, some of which were made available only recently in the course of several biographical research projects dealing with this revolutionary pedagogue and social entrepreneur.FindingsFirstly, the paper identifies similarities between the teaching practice at Eugenie Schwarzwald's schools, her approach to leadership on the one hand, and Drucker's principles of effective management and knowledge work on the other. Secondly, it concludes that in a knowledge society both effective management and teaching need to be extensively individualised services – much more than in an industrial mass society.Practical implicationsCombined, Schwarzwald's practice and Drucker's teachings challenge some seemingly up‐to‐date practices in both higher education and corporate personnel development, and helps in understanding what actually produces effective personal learning for the rapidly changing knowledge economies of the twenty‐first century.Originality/valueThe paper introduces selective aspects of progressive education to the field of management.
The art of managing for the future: leadership of turbulence
Authors: Lane David A. , Down Martin 
Published: May 2010

PurposeThe paper aims to explore themes in Drucker's work which provide messages for current turbulent times. Based on a literature review of both Drucker's work and contemporary studies in the field of complexity theory the paper's aim is to explore turbulence as a feature of levels of agreement for objectives and predictability of outcome. Drucker's concept of management as a social enterprise is seen as central together with his warning that the tools and techniques of management should not obscure its purpose.Design/methodology/approachThe paper provides a literature review and a brief case study. The review identifies that contemporary complexity theory can be used to explore Drucker's work on turbulence. The case study shows how approaches based on dialogue can enable conflicting objectives to be explored and agreed outcomes achieved.FindingsThe paper concludes that in turbulent times Drucker's concept of management as a social enterprise forms a core framework that can be used within complex situations to agree objectives through dialogue.Originality/valueThis paper uniquely links Drucker's work with contemporary complexity theory.
The challenge to rekindle China's innovative spirit
Authors: Kriz Anton 
Published: May 2010

PurposeChina has become an economic powerhouse in historic terms but there are a number of challenges to its continued prosperity. The aim of this paper is to more fully understand China's propensity for creative innovation, which is seen as an important next stage in its continued development.Design/methodology/approachThe paper is conceptual but uses historical and secondary data to support its assumptions. The paper was written in conjunction with the 1st Global Peter F. Drucker Forum (celebrating 100 years since his birth) and attempts to continue his challenge of “the hard work of thinking”.FindingsChina has a long history of successful innovation. However, Confucian belief, a single despot and a closing off to the rest of the world have thwarted its innovative edge. The key to rekindling the entrepreneurial spirit is seen largely as an internal battle based on the state's ability to balance the institution of government with the needs of a burgeoning prospective creative class. This paper identifies that much of this change will rely on quality‐related developments rather than simply investments of financial capital.Originality/valueThe ability to create new things is a challenge to developing economies that rely on low cost and imitation. China's success in innovation will have substantial implications for developed nations both economically and geo‐politically. China wants to be a significant player on a global scale and this paper sheds light on its potential to achieve such an objective. Through traversing China's innovative landscape, this paper also enlightens the field of management on key aspects of China's innovative past, present and future.
HKSAR government civil servants: a non‐Drucker organisation?
Authors: Kai Pong Leung Tony , Adams John 
Published: May 2010

PurposePeter F. Drucker (1909‐2005) was an influential modern management theorist. This paper, however, aims to challenge his diagnosis and prescriptions on the public sector for over‐simplifying several complex issues and not being sufficiently comprehensive. With the support of the empirical findings of a survey in the government of Hong Kong Special Administrative Region (HKSARG), the authors seek to supplement Drucker's discussion on government and to propose managerial actions for implementing change.Design/methodology/approachAn e‐mail questionnaire survey of 700 randomly selected government employees in Hong Kong was conducted. Additional information was gathered from senior management to validate the survey results.FindingsIn line with Drucker, HKSARG employees, as a whole, are reluctant to change. But statistical tests show that there are heterogeneous behavioural groups. Specifically, younger and more educated staff are more willing to change. The existence of these groups has both practical and managerial implications for implementing change.Research limitations/implicationsThe usable sample is relatively small (n=66).Practical implicationsThe government should not be viewed and understood unidirectionally. Management should target the younger and more educated users first to build up sufficient user mass and adopt peer pressure for a more successful level of implementation of IT usage across all staff. Job rotation and flexible entry and exit options are worth considering, too.Originality/valueThis research validates empirically the nature of HKSARG. It demonstrates that researchers' challenges to Drucker's views on government are well founded. More research on the characteristics of the public sector is required for better understanding of the real nature of these large, bureaucratic organisations.
Effect of particle transient motion on lubrication
Authors: Haiyan Han , Youyun Zhang , Zhenyuan Zhong 
Published: May 2010

PurposeThe purpose of this paper is to analyze the influence of particle motion on the lubrication characteristics. The dynamics of the particle in the lubricant is also studied.Design/methodology/approachThe dynamics of the particle is studied using Newton's second law. The particle dynamic equation is solved to determine the particle velocity, angular velocity, and location. The modified Reynolds equation is solved in couple with particle motion to determine the film pressure and velocity.FindingsThe motion of a particle suspended in the lube oil is clarified. The initial relative velocity between the particle and the fluid has a significant effect on the lubrication. For the same particle location and velocity, the larger particle or the closer distance between particle center and lower plate has greater effects on the film pressure.Research limitations/implicationsThe influence of the particle geometry on the lubrication is neglected in the study because of the small size of the particle, this neglect is idealized. Further study will take the effects of the particle geometry into consideration.Originality/valueThe paper provides the motion of the particle in the lubricant, and the modified Reynolds equation considering the particle translation as well as rotation is derived.
Oil‐ and water‐based continuous control valve
Authors: Majdic Franc , Pezdirnik Jozef 
Published: May 2010

PurposeEnvironmental protection regulations are becoming increasingly strict. Using water instead of a hydraulic mineral or biodegradable oil in power‐control hydraulic systems is a very positive step towards complying with these regulations. Since water hydraulics has many specifics, primarily related to lower viscosity and lubricity of water compared to oil, which greatly affects the leakage, and even more the friction and wear in these systems, a dedicated test rig is required for performing research with the real‐scale components. The purpose of this paper is to present some preliminary representative results on dynamic responses of the two hydraulic circuits with and without a mass load.Design/methodology/approachThe paper presents the newly developed dedicated test rig and its dynamic characteristics when used with water and oil as hydraulic fluid. Hydraulic pressures and motions of spool and piston in the two different fluids were of special interest.FindingsThe results clearly show their dependence on friction properties of selected materials in different hydraulic fluids. While the oil valve worked perfectly, water valve has some irregularity, linked with the small gap, the shape irregularity, the surface roughness and the poorer lubrication conditions in the water hydraulics compared to the oil system.Originality/valueThe observed irregularity of the movement of the spool in the water hydraulic valve has almost no influence on the movement of the piston rod of the water cylinder, which is a very promising result for future research on water hydraulics.
Minimization of power loss in tilting‐pad journal bearings
Authors: Saruhan Hamit 
Published: May 2010

PurposeThe purpose of this paper is to implement an optimization approach for the tilting‐pad journal bearing using the genetic algorithm (GA), and compare the results with the method of feasible design (MFD).Design/methodology/approachThe optimum design of a five‐pad tilting‐pad bearing is studied for the optimal performance, considering system minimum power loss along with design criteria such as: fluid film thickness, film temperature, and film pressure with respect to design variables consisting of pad axial length to journal diameter ratio, pad arc length, bearing radial clearance, pad offset factor, and pad preload factor.FindingsThe algorithms are repeated until no search direction can be found that will improve objective function without violating the constraints. Thus, the algorithms are performed for complete search to get the best possible solution of the design. The comparison mainly focuses on the empirical solutions. The GA obtained reasonably good results for the objective function and comparable to the MFD.Originality/valueThe availability of the GA is certainly of value because it allows the exploration of many different configurations of design variables and therefore also contributes to the better knowledge of the rotor‐bearing system behavior in general.
Synthesis and tribological behavior of ionic liquid substituted fluoroalkoxycyclophosphazene derivatives in steel‐steel contacts
Authors: Li Jinlong , Feng Dapeng , Liang Yongmin , Xia Yanqiu , Liu Weimin 
Published: May 2010

PurposeThe purpose of this paper is to synthesize a series of cyclophosphazene derivatives with better tribological properties.Design/methodology/approachTo improve the adsorptivity to substrate, a series of cyclophosphazene derivatives substituted with ionic liquids were synthesized. The lubricity characteristics of phosphazene derivatives were evaluated on an Optimol SRV IV oscillating friction and wear tester. Scanning electron microscope and X‐ray photoelectron spectroscope analyses were conducted to examine the morphology and chemical composition of the wear scars and the possible tribochemical changes involved in the friction process.FindingsAlkoxycyclophosphazene derivatives substituted with ionic liquids synthesized in the present work show better antiwear ability and load‐carrying capacity in steel‐steel contacts. The density of ion pairs plays an important role on tribological properties.Research limitations/implicationsThe paper deals with only a limited compounds and steel‐steel contacts. The paper works on the subject progressively to explore more combinations for better tribological properties.Practical implicationsAll the cyclophosphazene derivatives present better tribological performance and could be used as base oils, such as hard disk surface lubricants.Originality/valueIonic liquids are introduced to cyclophosphazene derivatives in this paper. This is a new method to improve the tribological properties of cyclophosphazene derivatives.
New Zealand unit trust disclosure: asset allocation, style analysis, and return attribution
Authors: Fowler Ross , Grieves Robin , Clay Singleton J. 
Published: May 2010

PurposeThis article aims to explore three facets of the historical performance of a sample of actively managed unit trusts available to New Zealand investors: asset allocation, style analysis, and return attribution.Design/methodology/approachBecause New Zealand does not require unit trusts to disclose their security holdings, the paper used returns‐based style analysis to infer how these trusts have allocated their funds among asset classes.FindingsThe research has found that, for unit trusts available to New Zealand investors, asset allocation can explain a significant amount of the differences in return across time and between trusts. Across time, asset allocation accounts for about 80 per cent of the variation in actual return. Between trusts, asset allocation explains about 60 per cent of the variation in returns. From either perspective, the choice of asset allocation is an important factor in explaining returns.Originality/valueThe paper suggests that active management barely earns its fees and that passive investments might do as well or better.
Actuarial gains and losses: the determinants of the accounting method
Authors: Morais Ana 
Published: May 2010

PurposeThe purpose of this paper is to investigate the determinants of the choice of the accounting method for recognising actuarial gains and losses of defined benefit plans.Design/methodology/approachIn the paper, a logit model is estimated in order to relate the dependent variable (actuarial gains and losses method) with some explanatory variables (size, industry, leverage, profitability, size of pension funds and the existence of actuarial gains or losses).FindingsThe results of this study indicate that size, industry, profitability and the existence of actuarial gains or actuarial losses are important determinants in the choice of the accounting method for actuarial gains and losses.Research limitations/implicationsThe study only addresses the choice between the equity recognition method and the corridor method due to the small number of companies that adopted the profit or loss method (only eight observations).Originality/valueThis paper examines the recognition of actuarial gains and losses which can have an economically significant impact on companies' financial position and financial performance. This paper contributes to the accounting choice literature by exploiting the determinants of the choice of the accounting method for recognising actuarial gains and losses under IAS 19.
Factors associated with the quality of audit committees
Authors: Baxter Peter 
Published: May 2010

PurposeThe purpose of this study is to analyse whether several indicators of audit committee quality are associated with a number of supply and demand factors such as board composition, board activity, auditor type and leverage.Design/methodology/approachThe 2001 annual reports of a random sample of 200 Australian listed companies were analysed and data gathered on several audit committee quality indicators, i.e. independence, expertise, size and activity. Regression analysis was performed to determine the level of association between these indicators and several board and other variables.FindingsThe results indicate that, in 2001, many Australian listed companies were already complying with several of the ASX Corporate Governance Council's recommendations relating to audit committees. Furthermore, in a time period absent of audit committee regulation, there was strong support for the influence of the board of directors on the composition and activity of the audit committee.Research limitation/implicationsConsistent with prior research, this study confirms the influence of the board of directors on a number of audit committee quality indicators.Practical implicationsCorporate regulators and companies will find these results useful to understand the factors driving several of the main indicators of audit committee quality.Originality/valueThis study adds to the current limited empirical research on Australian audit committees by analysing several indicators of audit committee quality in a time period not affected by regulation.
The journey from market orientation to firm performance
Authors: Chen‐Ho Chao Mike , Spillan John E. 
Published: May 2010

PurposeThis paper aims to investigate the link between market orientation and performance of US and Taiwanese small‐ and medium‐sized enterprises (SMEs). This study is primarily centred on empirically investigating two issues: test the effectiveness of MARKOR (a widely used market orientation measure developed by Kohli et al.) in US and Taiwanese SME contexts, and investigate the factors influencing US and Taiwanese SMEs’ performance.Design/methodology/approachThis study's participants were owners or managers from 138 SMEs located in three states in the USA (i.e. Maryland, New York, and Pennsylvania) and 151 SMEs located in Taiwan. A survey was created to collect data: market orientation scale items used in this survey were mainly adopted from MARKOR; performance scale items were adopted directly from previous studies. Structural equation modelling was employed to analyse the data collected.FindingsThis study finds that neither US and Taiwanese SMEs’ intelligence generation, nor intelligence dissemination had a significant relationship with their firm performance. However, the findings do indicate that there was a significantly positive link between US and Taiwanese SMEs’ responsiveness and their firm performance.Originality/valueIn almost all previous studies in this field, the primary emphasis has focused on the market orientation of large businesses. Research on market orientation in SMEs has been scarce. Hence, this paper contributes to the extant literature by changing the research direction and studying market orientation in SME context. In addition, this paper provides SME managers with a more understandable guide to specific market‐oriented activities.