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Due to the increase of power transmission capacity, once an active power vacancy happens, power systems will face a serious frequency instability problem. With the development of communication technology in cyber physical power system (CPPS), demand response (DR) resources can take the initiative to reduce electricity utilization in order to tackle the system under-frequency challenge. This paper presented a frequency control model for CPPS considering DR strategy to rapidly forecast the effects of DR sources participating in frequency control. The model was verified through a case study as well.

It is well-known that engineering is a key profession for both economic and social development. This is as true for China as it is for other countries which are in the process of development. However, what are the economic incentives for young people to enter the profession today? Currently, there are many studies of the rate of return to educational investment, but recent empirical studies of the rate of return to educational investment for engineers are uncommon. This is true generally, but especially for contemporary China. This is because it is difficult to obtain high-quality and representative sample data about engineers. This paper uses the data of the Chinese Family Panel Studies, 2010, and applies a Mincerian income function to estimate the rate of return to education for engineers who work in the private sector in urban China. The empirical results show that the rate of return for engineers is 12.3%, which is an impressive figure. It is in accordance with the current supply and demand of the Chinese labour market which requires many engineers to carry out construction and maintenance projects given China’s continuing industrialisation, modernisation and urbanisation. However, the empirical results also show that compared with the rate of return to education for professional and technical personnel who are employed in business economics and finance, the rate of return for engineers is significantly lower. This may explain why in China today the attraction of engineering education for talented young people is declining, with more and more students choosing business economics and finance as their first choices of major and career, rather than engineering as in the past.

Requirements engineering is a main question which spans across the whole software development lifecycle. Spacecraft’s software also needs to focus on software requirements, and manage the requirements across the entire software development lifecycle, including operation, maintenance, and the redevelopment. This paper summarizes six technologies and methods of requirement acquisition, including Interview, Questionnaires, Consult Strategic Objectives and Departmental Standards, Panel Discussions, Storyboard, Defect Tracking Management, analyzes different types of software requirement analysis combined with actual cases, Management software, Software for Scientific Research and production, Professional and Technical Software, these three types of software’s requirements engineering management. In the end, identifies some directions for future research. The aerospace company now more inclined to use all kinds of mature software platform based on a small amount of customization changes, succession advanced management concept in mature platform. It will improve the system stability, and at the same time, the flexibility of the excellent software platform can ensure the personal demands.

Nowadays, the power system is evolving into a complex cyber physical system with the closely merged physical system, information system, and communication network. It is critical to understand the connections between the power and cyber systems, and the potential impact of cyber vulnerability. In this study, a flexible hardware-in-the-loop (HIL) testbed is proposed for studying the cyber physical power system. By using the flexible interface, various co-simulation systems for different purposes are generated. Based on this testbed, three sample co-simulators are built as proofs. First, a HIL power and communication co-simulator with non-real-time synchronisation mechanism is introduced, and a case of false data injection attack on automation voltage control is studied. Then, a real-time power and communication HIL co-simulator is introduced, and a case considering the impact of communication bit error on the stability control system is simulated to demonstrate the performance of stability control equipment. Finally, another co-simulator for simulating the actual cyber-attack on the stability control system is introduced, and a case of a man-in-the-middle attack on the data link is simulated to demonstrate the impact of cyber-attack on the stability control system.

The safe and reliable transmission of relay protection signal is essential to the normal operation of relay protection device. Based on the characteristics of the protection signal transmission, this paper proposes a method to model the real time failure rate of the protection communication channel introduced by the communication latency and bit error. First of all, by using the decision tree method and processing the history fault data of the protection channels, communication equipment, board equipment and various function blocks, get the channel failure rate based on historical data. On this basis, according to protect channel signal delay and error performance requirements for the protection signal, propose a real-time channel failure rate model due to communication time delay and bit error. Finally, the application and effectiveness of the proposed channels real-time failure rate model are demonstrated on a typical example.

Although traditional Chinese education was characterized more by holistic than subject-based learning, only in the last century has the Western philosophy and practice of liberal education become familiar in Chinese higher education circles. With increasing contacts between China and the United States in the rst half of the twentieth century, American concepts of general and liberal education became popular in China. Colleges and universities founded by foreigners were especially likely to implement Western – often American-style – liberal arts curricula. For more than two decades after the creation of the People’s Republic of China, however, the government followed a model of higher education that emphasized rigid subject-based knowledge plus moral-political studies.