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According to the requirements of servicing and deorbiting the failure satellites, especially the tumbling ones on geosynchronous orbit, this paper aims to design a docking mechanism to capture these tumbling satellites in orbit, to analyze the dynamics of the docking system and to develop a new collision force-limited control method in various docking speeds.

The mechanism includes a cone-rod mechanism which captures the apogee engine with a full consideration of despinning and damping characteristics and a locking and releasing mechanism which rigidly connects the international standard interface ring (Marman rings, such as 937B, 1194 and 1194A mechanical interface). The docking mechanism was designed under-actuated, aimed to greatly reduce the difficulty of control and ensure the continuity, synchronization and force uniformity under the process of repeatedly capturing, despinning, locking and releasing the tumbling satellite. The dynamic model of docking mechanism was established, and the impact force was analyzed in the docking process. Furthermore, a collision detection and compliance control method is proposed by using the active force-limited Cartesian impedance control and passive damping mechanism design.

A variety of conditions were set for the docking kinematics and dynamics simulation. The simulation and low-speed docking experiment results showed that the force translation in the docking phase was stable, the mechanism design scheme was reasonable and feasible and the proposed force-limited Cartesian impedance control could detect the collision and keep the external force within the desired value.

The paper presents a universal docking mechanism and force-limited Cartesian impedance control approach to capture the tumbling non-cooperative satellite. The docking mechanism was designed under-actuated to greatly reduce the difficulty of control and ensure the continuity, synchronization and force uniformity. The dynamic model of docking mechanism was established. The impact force was controlled within desired value by using a combination of active force-limited control approach and passive damping mechanism.

The purpose of this paper is to present kinetic equations for tether-net system during deorbiting using a novel method differing from the traditional method.

The work presents kinetic equations for tether-net system in which the tether exhibits tensional and tensionless states alternately during deorbiting. Orbital position coordinates of net-capture and abandoned spacecrafts are adopted as generalized coordinates above-mentioned instead of librations and the length of the tether. Geostationary orbit (GEO) and the orbit whose apogee is 300 km above GEO are chosen as the initial and target orbit, respectively. Simulations are conducted to study the deorbiting results considering a variety of parameters and initial conditions.

The distinctive dynamic characteristics of tether-net system can be seen by kinetic equations based on the proposed dynamic modeling strategies. Moreover, the deorbiting results are deeply affected by the initial tension force and librations showed by simulations. The initial tension force and librations should be controlled within a reasonable range.

This is expected to provide dynamic modeling strategies for space tether-net system during deorbiting. Moreover, the preliminary principle of choosing initial conditions and parameters to meet the requirements for deorbiting can be achieved.

The research proposes a novel dynamic modeling method for space tether-net system that differs from traditional tethered system, and also proposes a superior librations expression based on orbital position coordinates of net-capture and abandoned spacecrafts.

In manufacturing, corporate growth and profitability are more challenging than ever before. The company reviewed in this study has been and is currently suffering tremendous growing pains with poor record of profitability. This paper reports learning and application of a few significant techniques to improve basic business practices in a company, which manufactures large volume, high quality optical thin film coatings. Some of the tasks involved in identifying opportunities for improving operational efficiencies included analysis of current business processes, identification of non‐value‐added activities including wastes and proposing process changes. Process mapping and kaizen “blitz” activities were utilized during analysis of key business processes within this company. The study demonstrates measurable results realized through use of process mapping tools, kaizen blitz activities, formalized and documented work instructions and work measurement tools. To ultimately be successful, a company must educate their workforce and create a fulfilling work environment for each of their employees. Worker involvement is essential and critical in today's society. Gaining the worker's trust and commitment is extremely important.

The purpose of this paper is to present principles for personalization of both learning content and gameplay in serious games for learning, which are based on a combined model of the student that comprises user, learner and player-related aspects of the student’s profile. Each of the considered user, learner and player sub-models has a static and dynamic group of characteristics. These characteristics assist general approaches for learning mazes game personalization applied to embedded mini-games (designed as information units, learning objects and educational tasks) so that to be adjustable and to enable learners to acquire knowledge more effectively.

A student modelling approach was applied to design the personalization of learning content in the educational maze game and each of them contained mini-games. To evaluate the student’s preferences about the types of mini-games and ways of their personalization depending on individual and group student characteristics, the authors conducted an online survey.

This study presents examples of personalization of four types of mini-games available in maze halls, namely, question, searching, arranging and action games. Next, the research discusses findings from an online survey aiming at the evaluation of the preferred types of mini-games and the way of their personalization. There are analysed results concerning the impact of the student model characteristics on the preferred ways of personalization in educational maze games, together with criteria for personalization of educational resources according to student’s level of knowledge, age, goals and learning style.

A significant limitation of the research is the relatively small number of survey participants and the lack of studying the impact of learning and playing styles over game personalization. Another limitation of the study is the inclusion of only some of the mini-games within the demonstration maze, which respondents play before answering the survey questions.

This paper presents original research on the personalization of educational maze game based on a model of the student profile that comprises both static and dynamic properties reflecting user, learner and player-related aspects of the student character, together with results obtained from an online survey.

In order to solve nonplanar LEO‐LEO aeroassisted space rendezvous, this paper aims to study an active phasing method based on orbital preliminary adjusting scheme out of atmosphere.

In order to add atmospheric entry velocity, orbital preliminary adjusting out of atmosphere is presented and the orbital altitude of high earth orbit (HEO) is selected eclectically. Nonplanar HEO‐LEO aeroassisted orbital transfer problem is studied in detail. According to the standard atmospheric flight trajectory, the locations of deorbit points in HEO are determined and the standard phase angle between orbital transfer vehicle (OTV) in HEO and target in low earth orbit (LEO) is obtained so that OTV and target meet space rendezvous demand. Finally, the active phasing method is studied so that the standard phase angle can be satisfied when OTV is transferred to HEO. So space rendezvous can be realized under the help of aeroassisted orbital transfer technique once the standard phase angle is satisfied.

Nonplanar LEO‐LEO orbital transfer depending on entirely propulsive will use enormous fuel and the phasing problem will be most difficult in nonplanar LEO‐LEO space rendezvous mission. However, the fuel consumption can be saved and rendezvous mission can be finished in an advisable time when nonplanar LEO‐LEO aeroassisted orbital transfer technology is applied properly.

Aeroassisted space rendezvous method is presented in this paper. Orbital preliminary adjusting out of atmosphere is studied in order to add atmospheric entry velocity and the active phasing method for realizing space rendezvous is integrated in preliminary adjusting scheme.

THROUGHOUT history certain decades emerge which are of cardinal import to mankind, like the one beginning in 1781, when the inventions of fifty years reached their apogee and through general application transformed the prevailing cottage industry into what we now call the factory system. That vast accretion of resources changed the human environment.

This journal often reports on new devices and items of equipment but, by the very nature of things it seldom has an opportunity to try them out on a personal basis. After all, the company secretary does have a right to object to an editor installing a wind tunnel or an engine test cell in that empty corner of the accounts department!

Few aircraft engine facilities are capable of handling large high by‐pass ratio turbofans and it is hoped that other airlines will place contracts at Prestwick.

The purpose of this paper is to present the aerodynamic analysis and external ballistics modeling used in the development of a rocket-target for short range air defence missile systems.

A computational fluid dynamics (CFD) analysis of the airflow around the rocket-target was carried out to estimate the drag, which was needed to develop a mathematical model for external ballistics of the rocket-target. Field-experimental testing was conducted to compare the model results to the data obtained experimentally using various additional measurement techniques such as global positioning system (GPS) coordinates marking of the crash and launch sites, air defence surveillance radar tracking and installing equipment for telemetric data capturing and transmission.

Various ballistic parameters such as the velocity and trajectory of the rocket-target were obtained taking into account the CFD analysis results and internal ballistics data. The field-experimental testing showed a good agreement between the model results and the results obtained by the experimental techniques.

The presented computational models and the experimental techniques could be used in future developments of similar aircraft.

This paper presents a research approach for developing a rocket-target. The results of the research were used as a basis for developing a rocket-target for short range air defence rocket systems. The developed rocket-target was successfully implemented in practice.

This chapter reassesses the economics of interest rate risk management in light of the global financial crisis by developing a derivative-based integrated treatment of interest rate and credit risk interrelation. The decade-long historical data on credit default swap spreads and interest rate swap rates are used as proxy measures for credit risk and interest rate risk, respectively. An elasticity of interest rate risk and credit risk, considered a function of the business cycle phases, maturity of instruments, economic sector, creditworthiness, and other macroeconomic parameters, is investigated for optimizing economic capital. This chapter sheds light on how financial institutions may address hedge strategies against downside risks implementing the proposed derivative-based integrated treatment of interest rate and credit risk assessment allowing for optimization of interest rate swap contracts. The developed framework of integrated interest rate and credit risk management is of special importance for emerging markets heavily dependent on foreign capital as it potentially allows emerging market banks to improve risk management practices in terms of capital adequacy and Basel III rules. Analyzing diversification versus compounding effects, it allows enhancing financial stability through jointly optimizing Pillar 1 and Pillar 2 economic capital.