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This paper reviews the normative literature of performance measurement within the context of Public-Private Partnerships (PPPs). The purpose of this paper is to examine the effectiveness of current ex post evaluations of PPPs and identify a feasible direction to comprehensively and effectively measure the performance of PPP infrastructure projects.

An in-depth literature review is conducted in this paper. The focus of the review is associated with the general performance measurement and performance measurements of PPPs.

This paper identifies that conventional ex post evaluation is not robust enough to measure the performance of PPP projects. Based on the characteristics of PPPs, the life-cycle (process-based) evaluation under performance measurement system is a promising approach to comprehensive and effective PPP performance measurement.

The outcomes of this paper can be used as a theoretical base for the development of PPP performance measurement framework.

Performance measurement is essential to business success, whether it is at the organisation or project level. Limitations on public funds have encouraged more and more governments across the world to use PPPs to procure economic and social infrastructure projects. Similar to traditional procurement, ex post evaluation is being widely used in PPP projects. However, PPPs are more complicated than other traditional procurement approaches. Exploration of literature suggests that limited research has been undertaken to examine if conventional ex post evaluation is sufficient to measure the performance of PPPs. This paper will bridge this significant knowledge gap.

The purpose of this paper is to review the normative literature in regard to public-private partnerships (PPPs) and their evaluations, and attempts to investigate whether the Performance Prism is a feasible framework for effective PPP performance measurement.

An in-depth and critical literature review is conducted in this study. Discussion concentrates on PPP features, performance measurement in PPPs, performance measurement in construction, and characteristics of the Performance Prism.

The Performance Prism exhibits a strong ability to capture the distinct features of PPP infrastructure projects and can be considered as a framework suitable for effective and efficient performance measurement.

It is essential that stakeholders have a feasible performance measurement framework to effectively measure performance as they embark on PPP infrastructure projects. This paper can be used as a theoretical base and conceptual framework capable of assisting in the design and selection of effective performance measures for PPPs.

Many governments across the world use PPPs to procure public assets owing to the scarce funds available for infrastructure development. Effective performance measurement is critical to the successful delivery of a PPP project. Conventional ex post evaluation that solely focuses on meeting budget and predetermined project duration is being widely used to measure PPPs in practice. PPPs are more complicated than traditional procurement due to their multiple stakeholder integrations and long-term processes. However, the research on effective PPP performance measurement is limited for addressing such vital issues, and this paper attempts to bridge this knowledge gap.

In this paper, with the goal of reducing the fuel consumption of UAV, the engine performance optimization is studied and on the basis of aircraft/engine integrated control, the minimum fuel consumption optimization method of engine given thrust is proposed. In the case of keeping the given thrust of the engine unchanged, the main fuel flow of the engine without being connected to the afterburner is optimally controlled so as to minimize the fuel consumption.

In this study, the reference model real-time optimization control method is adopted. The engine reference model uses a nonlinear real-time mathematical model of a certain engine component method. The quasi-Newton method is adopted in the optimization algorithm. According to the optimization variable nozzle area, the turbine drop-pressure ratio corresponding to the optimized nozzle area is calculated, which is superimposed with the difference of the drop-pressure ratio of the conventional control plan and output to the conventional nozzle controller of the engine. The nozzle area is controlled by the conventional nozzle controller.

The engine real-time minimum fuel consumption optimization control method studied in this study can significantly reduce the engine fuel consumption rate under a given thrust. At the work point, this is a low-altitude large Mach work point, which is relatively close to the edge of the flight envelope. Before turning on the optimization controller, the fuel consumption is 0.8124 kg/s. After turning on the optimization controller, you can see that the fuel supply has decreased by about 4%. At this time, the speed of the high-pressure rotor is about 94% and the temperature after the turbine can remain stable all the time.

The optimal control method of minimum fuel consumption for the given thrust of UAV is proposed in this paper and the optimal control is carried out for the nozzle area of the engine. At the same time, a method is proposed to indirectly control the nozzle area by changing the turbine pressure ratio. The relevant UAV and its power plant designers and developers may consider the results of this study to reach a feasible solution to reduce the fuel consumption of UAV.

Fuel consumption optimization can save fuel consumption during aircraft cruising, increase the economy of commercial aircraft and improve the combat radius of military aircraft. With the increasingly wide application of UAVs in military and civilian fields, the demand for energy-saving and emission reduction will promote the UAV industry to improve the awareness of environmental protection and reduce the cost of UAV use and operation.