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This paper aims to describe a novel type of attitude control system (ACS) in different configurations. This servomechanism is compared with control moment gyro (CMG) in significant parameters of performance for ACS of rigid satellite.

This new actuator is the fluid containing one or more rings and fluid flow is supplied by pump. The required torque control is obtained by managing fluid angular velocity. The cube-shaped satellite with three rings of fluid in the principle axes is considered for modeling. The satellite is considered rigid and nonlinear dynamics equation is used for it. In addition, the failure of the pyramid-shaped satellite with an additional ring fluid is discussed.

The controller model for four fluid rings has more complexity than for three fluid rings. The simulation results illustrated that four fluid rings need less energy for stabilization than three fluid rings. The performance of this type of actuator is compared with CMG. At last, it is demonstrated that performance parameters are improved with fluid ring actuator.

Fluid ring actuator can be affected by environmental pressure and temperature. Therefore, freezing and boiling temperature of the fluid should be considered in system designation.

Fluid ring servomechanism can be used as ACS in rigid satellites. This actuator is compared by CMG, the prevalent actuator. It has less displacement attitude maneuver.

The results provide the feasibility and advantages of using fluid rings as satellite ACS. The quaternion error controller is used for this model to enhance its performance.

Demonstrates how management consultancy CMG has conserved its open culture, despite having grown dramatically in size. Identifies the ways in which the company transfers its strong culture to newly acquired companies through Training and education. Notes that the adoption of a TQM policy over the last few years has been seen as the next step in maintaining and improving the working environment, and also as a way of helping staff to approach the issue of quality in a more specific way.

This paper aims to investigate the attitude control pointing improvement for a small satellite with control moment gyroscopes (CMGs) using the active force control (AFC) method.

The AFC method is developed with its governing equations and integrated into the conventional proportional-derivative (PD) controller of a closed-loop satellite attitude control system. Two numerical simulations of an identical attitude control mission namely the PD controller and the PD+AFC controller were carried out using the MATLAB^®-SimulinkTM software and their attitude control performances were demonstrated accordingly.

Having the PD+AFC controller, the attitude maneuver can be completed within the desired slew rate, which is about 2.14 degree/s and the attitude pointing accuracies for the roll, pitch and yaw angles have improved significantly by more than 85% in comparison with the PD controller alone. Moreover, the implementation of the AFC into the conventional PD controller does not cause significant difference on the physical structure of the four single gimbal CMGs (4-SGCMGs).

To achieve a precise attitude pointing mission, the AFC method can be applied directly to the existing conventional PD attitude control system of a CMG-based satellite. In this case, the AFC is indeed the backbone for the satellite attitude performance improvement.

The present study demonstrates that the attitude pointing of a small satellite with CMGs is improved through the implementation of the AFC scheme into the PD controller.

The purpose of the paper is to design a new attitude stabilization system for a microsatellite based on single gimbal control moment gyro (SGCMG) in which the gimbal rates are selected as controller parameters.

In the stability mode, linear quadratic regulator (LQR) and linear quadratic Gaussian (LQG) control strategies are presented with the gimbal rates as a controller parameters. Instead of developing a control torque to solve the attitude problem, the attitude controller is developed in terms of the control moment gyroscope gimbal angular velocities. Attitude control torques are generated by means of a four SGCMG pyramid cluster.

Numerical simulation results are provided to show the efficiency of the proposed controllers. Simulation results show that this method could stabilize satellite from initial condition with large angles and with more accuracy in comparison with feedback quaternion and proportional-integral-derivative controllers. These results show the effect of filtering the noisy signal in the LQG controller. LQG in comparison to LQR is more realistic.

The LQR method is more appropriate for the systems that have project models reasonably exact and ideal sensors/actuators. LQG is more realistic, and it can be used when not all of the states are available or when the system presents noises. LQR/LQG controller can be used in the stabilization mode of satellite attitude control.

The originality of this paper is designing a new attitude stabilization system for an agile microsatellite using LQR and LQG controllers.

This study of 216 congestive heart failure (CHF) patients at a large teaching hospital in south‐central Ontario was undertaken to determine whether the patients managed in an outpatient heart failure clinic used fewer hospital resources (as expressed in number of admissions, complexity of admission, and length of stay (LOS)) than a matched cohort who were not managed in an outpatient clinic. Statistical significance of LOS opportunities could not be demonstrated (owing to sample size), however, the heart failure clinic is making a positive impact on all types of admissions (CHF and non‐CHF) in terms of LOS and suggests that management in an outpatient setting for chronic disease states is important for acute care hospitals to consider.

The paper aims to cover the institutional decision‐making processes behind the decision to add machine readable cataloging records to the library catalog that link to hundreds of thousands of URLs with freely available web content, the management processes making this possible, as well as other more philosophical concerns.

This is a case study conducted at the University of Denver, Penrose Library.

Implementing a URL tracking system, combined with a philosophical decision to follow a proactive URL maintenance approach rather than a reactive one, has resulted in an improved error rate for URL click‐throughs.

The paper addresses URL maintenance issues, staffing solutions, and error rates not addressed elsewhere in the literature.

Discusses the concept of networking structure for the co‐ordination in the corporate decision‐making process in Japan. Looks at networking at a micro level based on empirical and anecdotal evidence.

Mergers bring with them a host of issues and can represent a major challenge for HR. The 2002 merger that formed LogicaCMG was seen as an opportunity to combine the strengths of the two legacy companies and roll out best practice HR programs. Nigel Perks, group HR director, explains how they did it.

Mr. V. Cavendish‐Bentinck CMG, chairman of Bayer UK Ltd., has just announced a new step by the company to contribute towards the protection of the environment, an issue which, he says, ‘is creating the atmosphere of tomorrow: the heritage we pass on to our children.’

Public–private partnerships (PPPs) have emerged in developing countries, such as China, as a ubiquitous means by which government procures needed infrastructure. In this regard, they have been much studied. However, due to their long concession period, running into decades, few have run their full course into the transfer phase (TP) in which the PPP concession reverts from the private entity back to the public. In China, this is about to change as many PPPs approach their TP. Hence, the purpose of this paper is to comprehensively investigate the TP of PPPs in China.

A three-part methodology was undertaken to achieve the research purpose. Extensive literature review was first conducted to analyze the status quo of the transfer management regime in China, followed by the identification of critical challenges and the exploration of solutions via studying the TP of the Chengdu No. 6 Water Plant B Project – the first PPP in China’s water sector to reach the TP. Research procedures and outcomes were hierarchically visualized by using Integration DEFinition language 0 (IDEF0) method.

The current transfer management regime of PPPs in China’s water sector is deficient in many aspects. Based on the insight into the practice, a generic transfer process model with hierarchical structure process and sub-processes serving as a dynamic framework transfer model with self-evolving nature is developed to facilitate the successful transfer of the PPP utility.

To the authors’ best knowledge, this is the first attempt to systematically probe the TP of PPPs. Hopefully, the findings of this paper are to instruct government and PPP practitioners alike on mechanisms for smoothing the TP of further PPP projects ending their concession period.