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This paper aims to investigate the problem of on-line orbit planning and guidance for an advanced upper stage.

The double impulse optimal transfer orbit is planned by the Lambert algorithm and the improved particle swarm optimization (IPSO) method, which can reduce the total velocity increment of the transfer orbit. More specially, a simplified formula is developed to obtain the working time of the main engine for two phases of flight based on the theorem of impulse. Subsequently, the true anomalies of the start position and the end position for both two phases are planned by the Newton iterative algorithm and the Kepler equation. Finally, the first phase of flight is guided by a novel iterative guidance (NIG) law based on the true anomaly update with respect to the geometrical relationship. Also, a completely analytical powered explicit guidance (APEG) law is presented to realize orbital injection for the second phase of flight.

Simulations including Monte Carlo and three typical orbit transfer missions are carried out to demonstrate the efficiency of the proposed scheme.

A novel on-line orbit planning algorithm is developed based on the Lambert problem, IPSO optimization method and Newton iterative algorithm. The NIG and APEG are presented to realize the designed transfer orbit for the first and second phases of flight. Both two guidance laws achieve higher orbit injection accuracies than traditional guidance laws.

A brief update on new developments in all spheres of education in Finland is provided. The qualitative and quantitative development has transformed the pre‐school kindergarten system, created a new comprehensive system and upgraded teacher training to university degree level. Vocational education and modular syllabuses are all aspects of the reformed nature of public education.

Real options available to developers and leading to an active and dynamic development of real estate assets are numerous. The purpose of the article is twofold. First, a conceptual framework is proposed as a practical aid for recognizing and understanding some frequently recurring combinations of options (such as deferral and expansion options). Based on the definition and classification of real options available in real estate markets, a comprehensive valuation tool for quantifying the value of those options embedded in a real estate development project is thus developed using a portfolio view.

Based on standard option pricing techniques, the proposed conceptual methodology is validated by applying it to an actual case of an investment for the construction of a new, multi‐purpose building in the semi‐central zone of the urban area of Rome (Italy).

Based on a static land value of €34.7 million, a waiting mode (deferral option) at an early stage of developing a property accounts for 16 percent of the expanded land value of the project, with 8 percent of such value being contributed by the expansion option. A real options valuation of the options portfolio available to a real estate developer enables increasing the project value by 31.1 percent as opposed to a traditional DCF analysis. In line with financial options theory, values of real options increase as volatility rises.

The case‐based analysis highlights that: flexibility in real estate development may create additional value enabling real estate developers or funds to react to market trends as new information arrives and uncertainty on fundamental factors (e.g. property prices) unfolds; the extra value added by managerial flexibility is neglected by DCF/NPV techniques; contrary to the common criticism on its lack of rigor, option valuation theory is suitable for appraising real estate assets; a portfolio approach is crucial when multiple real options exist.

Active management of real estate investments in response to changing property market and technology conditions confers operating flexibility and strategic value to appraisal of development projects beyond what is traditionally captured by a DCF model. An options approach to valuing and managing real estate development may change the developer's perspective altogether. Based on the combination of an original classification and a portfolio view of options existing in real estate markets, a real options framework for assessing the value of strategic flexibility incorporated in a greenfield development project (also accounting for potential option interactions) is designed.

This study aims to present a method for conceptual design and simulation of hybrid propellant motors.

The design methodology is based on previous studies and thermo-physical governor relations, and also a computational code that was derived to simulate the performance of designed system.

Conceptual design algorithm for space hybrid propellant systems and method of performance simulation are findings of this study.

Results of this study are applicable for design process of space systems with hybrid propulsion. Also, simulation results can help the users to improve the performance weaknesses.

This study shows the implementation of present algorithm for a specified space mission and also study on variation of performance parameters.

The socialist political economy with Chinese characteristics reflects the characteristics of ushering into a new era, and the research object thereof shifts to productive forces. Emancipating and developing productive forces and achieving common prosperity become the main theme. Wealth supersedes value as the fundamental category of economic analysis.

The theoretical system of socialist political economy with Chinese characteristics cannot proceed from transcendental theories but is problem-oriented. Leading problems involve development stages and research-level problems.

The economic operation analysis is subject to the goal of optimal allocation of resources with micro-level analysis focused on efficiency and macro-level analysis focused on economic growth and macroeconomic stability also known as economic security. The economic development analysis explores the laws of development and related development concepts in compliance with laws of productive forces. The new development concepts i.e. the innovative coordinated green open and shared development drive the innovation of development theory in political economy.

Accordingly, the political economy cannot study the system only, but also needs to study the problems of economic operation and economic development. Therefore, the theoretical system of the political economy tends to encompass three major parts, namely economic system, economic operation and economic development (including foreign economy). The basic economic system analysis needs to understand the relationship between public ownership and non-public ownership, between distribution according to work and factor payments, and between socialism and market economy from the perspective of coexistence theory, thus transforming institutional advantage into governance advantage.

The most costly part in an open-pit mine is the transportation of material out of the mine. The efficiency of the truck-and-shovel fleet plays a major role in cost control. The paper aims to discuss these issues.

The truck dispatching simulation model with consideration of age-based maintenance is proposed.

This paper underlines an impact of truck dispatching decisions and reveals remarkable differences in the total production under different approaches of operational availability. Additionally, the simulated results introduce an effective scheduled maintenance for different truck age levels.

The approach is based on a case study taking into account the stochastic equipment behavior and environment in a real open-pit mine. This approach can be used more generally in situations in which truck fleets are used to transport material.

The purpose of this paper is to identify factors which influence the sustainability of selected German agri‐food chains.

The paper is composed of a literature review, qualitative and quantitative expert interviews, and structural equation modelling.

Effective communication, the existence of personal bonds and equal power distribution between buyers and suppliers are key determinants of sustainable vertical business relationships. The relevance and significance of the determinants differ across the investigated chain stages (farmer‐processor versus processor‐retailer), the use of formal versus non‐formal relationship types and the maturity of a relationship.

Further research needs to empirically apply the analysis to agri‐food chains other than the investigated pig‐meat and cereal ones.

Agribusiness and farm managers can enhance the sustainability of their business relationships by effective communication by fostering personal bonds with their suppliers and/or buyers, and by employing – and retaining – key staff who fit culturally and/or socially with those with whom they transact. Finally, managers also need to be aware of the fact that a business relationship can be negatively affected by abusing a more powerful market position.

A model for measuring the sustainability of vertical business relationships is presented and empirically tested. In addition, factors influencing the sustainability of these relationships are identified for the case of selected German agri‐food chains.

This paper aims to suggest a new revolutionary method and installation for flight on Earth and into outer space.

Methods of electromagnetic physics are used for research and the theory of levitation vehicles is developed and its possibilities researched.

It was found that levitation devices and electricity storage make a jump in aviation, space, storage and transfer energy and many branches of industry.

Many projects were calculated using different versions of the offered AB engine: a small device for levitation‐flight of a human (including flight from Earth to outer space), fly VTOL car (track), big VTOL aircraft, suspended low‐altitude stationary satellite, powerful Space Shuttle‐like booster for travel to the Moon and Mars without spending energy (spent energy is replenished in braking when the ship returns from another planet to its point of origin), using AB‐devices in military, in sea‐going ships (submarines), in energy industry (for example, as small storage of electric energy) and so on. The vehicles equipped with AB propulsion can take flight for days and cover distances of 10,000s of kilometers at hypersonic or extra‐atmosphere space speeds.

The paper promises a new revolutionary method of flight on Earth and into outer space.

The purpose of this paper is to examine the challenges encountered in e‐government implementation, as well as the potential opportunities available in the context of Jordanian society.

A detailed examination and analysis of Jordan's published e‐government vision and strategy is presented, together with a review of other relevant literature.

The findings and implications of this study reveal Jordan is still lagging behind in utilising information and communication technologies for delivering government services online.

An understanding of the current status of e‐government in Jordan can help policy makers in the country pursue development of the public sector organisations on the one hand, and would be of importance for Jordan's economic future success on the other.

This is believed to be the most up‐to‐date and comprehensive analysis of Jordan's plans and assessment of its level of readiness for delivery of e‐government services.

Employee participation is conceived as a four‐stage process (interaction, communication to and from management, influence by and on management, employee effect on decisions). Eighty‐two lower supervisory managers perceived the four stages as highly related except for influence by management. Further, the four processes of participation were found in approximately equal amounts (except for managerial influence). An examination by decision type showed that employee and managerial influence were inversely related on corporate and departmental decisions, but were unrelated on departmental employee and operational decisions. Employees engaged most in participation on departmental employee decisions and least on departmental staffing decisions. This difference in participation was greater for organisations of small size.