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The path congestion and communication risks of electric power communication network have emerged as the carried businesses are becoming more and more heavy. In this paper, a multi-objective optimization method for power communication network routing considering the importance of the carried businesses is proposed to reduce load imbalance and transmission risk. Firstly, information entropy is introduced as the objective of communication network load balancing optimization. And a risk assessment model for power communication network nodes and links is established. Then fuzzy membership functions are adopted to singularize the two objectives to jointly optimize path congestion and communication risks. The device nodes are dynamically divided according to the carried businesses to pursue the global optimization of the power communication network in which the Yen's algorithm is adopted. Finally, this paper uses the IEEE 30-bus communication network to carry out case simulations and analyzes the proposed method to verify the effectiveness and feasibility.

Abstract Domestic wind turbine manufacturing sector in China has experienced development stages starting from scratch to mass production. During the 11th FYP period (2006–2010), the main goal of wind power policy in China is to promote the commercialization of wind power by large-scale deployment of wind farms. This goal has been realized to a great extent and now the cost of wind power generation is nearly comparable to coal-fired power generation in China. The industry policy, which devotes to mass production of domestic wind turbines, is also largely successful. The purpose of the paper is to provide an overview on wind turbine manufacturing sector in China. The policy evolution in different stages, achievements and challenges pertinent to the sector are addressed in the paper. Key findings are that the misleading industry policy, which provides strong incentive to blind entrance and “competition for scale and price” and restrains innovation as well, is the key obstacle for the sustainable development of the sector. Deficient technology standard and qualification system and the misplaced franchise bidding system also indulge vicious competition and oversupply. Creating a level playground for all turbine supplies, providing strong incentive to innovative manufacturers, establishing thorough and practicable standard and qualification system, and fine-tuning the directive of the franchise bidding system towards technology and service are the primary policy implications proposed by our study.

We researched China's climate and sustainable development goal with relevant and susceptible instruments capable of inducing and mitigating carbon emissions. Amidst the contributor to the global carbon emissions, China is caught in between mitigating its carbon emission and aiming towards placing its national contribution of emissions to the acceptable levels of 1.5 °C and below 2 °C. Following the intricacies surrounding China's sustainable development as it contains its economic and environmental performance, we adopt China's data of 1980 and 2018 with different scientific approaches (nonlinear autoregressive distributed lag (NARDL), dynamic ordinary least square test, and bootstrap Granger causality) with different instruments (such as economic growth, financial development, renewable energy, and innovation policies) to research China's sustainable development. For clear exposition and insight into our findings with policies attached, we draw a conclusion from the outcomes of the mentioned approaches. From NARDL and dynamic ordinary least squares (DOLS), we find that economic growth through economic activities is statistically significant in determining the trend (increase) of carbon emissions in China in both periods (short run and long run). However, other selected instruments (financial, renewable, and innovation policies) tend towards controlling and moderating the carbon emissions in China. Thus, China has good prospects to mitigate its carbon emissions if considered tailoring its policies towards favorable instruments. From bootstrap Granger causality, we find similar inferential results that support previous findings thereby confirming the positive implication of the selected instruments to China's sustainable development. Hence, the nexus that is established among the selected instruments clearly show the importance of technological innovation and renewable energy in mitigating carbon emissions.

Clean-tech industry, also identified as the advanced stage of eco-friendly industry and typical high-tech, has to gain enough financial support to develop. Meanwhile, it has provided substantial market opportunities as well as investment options for venture capitalist. In an attempt to form a comprehensive understanding of VC policy preferences in clean-tech sector, relevant studies have been done by researchers from organizations, universities, and firms, from various perspectives, forming an independent “niche” research field. Based on the interactive relation between industry development and clean-tech investing, this paper performs a time-sharing, multidimensional, and dynamic review on international clean-tech policies literatures, focusing primarily on investor preferences. We aim to provide references to the lenses and methods currently used for future research including policy tool design, investment attraction effects, and policy efficiency. Moreover, the findings facilitate the innovation and expansion of related research for China, by which it can form effective financial support for domestic clean-tech industry.

The offshore wells are subject to hostile environments of such areas as the North Sea, GOM and the high arctic. The strong loop ocean currents and induced eddies can pose significant problems for deep-water well. Broadly divided ocean currents, surface currents, bottom currents and vertical currents, interact with the deep water well structures as one of environmental forces. One of the engineering challenges in deep water drilling is temperature gradient. In the past the temperature in the wellbore was ignored and an isothermal system was assumed because no practical means existed to determine the well bore temperature profile. But the fact is that the negative thermal gradient exists between surface to seafloor and it becomes positive below the seafloor. The extreme values could be as low as 40°F and as high as 150∼200°F. In addition to low temperature condition, the significant heat exchange also occurs for high temperature and geothermal reservoirs. The universal matrix form of implicit finite differential equations is introduced to predict the temperature profile of the fluid in the well and near-wellbore formation. This paper is to combine various factors together to derive a solver for the transient temperature modeling during the dirculation of riserless drilling, which can be the basis to describe the near-wellbore well stability under geo-thermal stress and predict the annular pressure during HPHT injection or production, which can also be used to including but not limited to the dynamic temperature profile and bottom-hole temperature, improving cementing program design, casing thermal stresses to be determined.

The power system ranks the first among the greatest engineering achievements in the 20th century. With “strong electric power” as the carrier, the power system constitutes the great aorta of modern society for energy transmission; while with “weak electric power” as the carrier, the information network constitutes the nervous system of modern society. Both of them penetrate into all aspects of human society (e.g., science, production, life, international relations), and then promote the modern civilization to achieve rapid development. In terms of science, the power system has promoted the developments of materials, physics, chemistry, automation, information, medicine, and so on. This way, the system of modern science and technology is constituted. In terms of production, the second industrial revolution marked by the wide application of “strong electric power” is also called the electric power technology revolution. It has promoted another major leap in the productivity of human society after the steam revolution. The third industrial revolution marked by the widespread application of “weak electricity” is also known as the information technology revolution, which promotes the continuous evolution of industrial civilization to a much higher level. And the fourth industrial revolution, which is centered on the energy revolution, will meet the needs of human beings at a higher level and get rid of the constraints of the environment on human activities. In terms of life, electric power has become the most indispensable part of human life, ranging from material life to spiritual life, from behavioral habits to thinking ways, and from personal life to social life. In terms of international relations, the development of the power system is conducive to the fundamental solution of energy and environmental problems, thus the international political and economic competition around energy and environment has turned to the competition centered on clean power systems to some extent. As the basic platform for energy production and supply, the development of the future power system must follow the general orientation of the energy revolution. The basic form, management mechanism and technical characteristics of the power system will also undergo tremendous changes as follows: (1) The proportion of renewable energy in the power system will be increased continuously, and the power system will be tightly coupled with gas system and thermal system to form an electricity-centric energy internet. (2) The development mode of building “higher, farther and larger” power grid will turn to the co-development mode of large power grid and small power grid, and the trend of power electronation of power system will be strengthened gradually. (3) Market competition will penetrate into the weak monopolies of the power system. Each subject can play a full game in each link, so as to obtain the optimal allocation of funds, technology and human resources. (4) Digitalization and intellectualization will be the most important technical characteristics of the future power system, which will achieve leapfrog development in observability, controllability and intellectualization.

Renewable energy technological innovation (RETI) is an important way to reduce carbon emissions and achieve sustainable development. Exploring whether RETI is beneficial to the improvement of carbon emission efficiency and how the market environment affects the role of RETI on carbon emission efficiency is critical to the design of effective policies. Therefore, based on the data from 25 provinces in China from 2002 to 2015, the Tobit fixed-effect model and the panel threshold model are used to investigate the impact and the mechanism of RETI on total factor carbon performance index (TCPI) from a market perspective. The results show that: (1) RETI can effectively improve TCPI, but this effect is affected by market factors; (2) With the reduction of market segmentation or the increase of market potential, the improvement effect of RETI on TCPI is significantly enhanced; (3) The panel threshold model further verifies that the impact of RETI on TCPI has a significant single threshold effect in terms of market segmentation and market potential; (4) There is an inverted "U-shaped" relationship between market segmentation and TCPI, and the increase of market potential is conducive to the improvement of TCPI. This paper provides corresponding policy implications for China to achieve the dual goals of economic transformation and carbon emission reduction.

Abstract With the rapid rise of installed nuclear power in China, meeting the increasing demands on natural uranium and rationally treating the vast spent fuel are essential issues for the sustainable development of Chinese nuclear power industry. This paper discusses four most potential nuclear fuel cycle modes in China and analyzes the natural uranium requirements under these different fuel cycle modes first based on three development patterns (low-, medium-, and high-speed) of installed nuclear power capacity. Then, an optimization model including natural uranium requirements, spent fuel final disposal amounts and total cost of electricity generation is constructed and optimization problem under two scenarios of reprocessing capacity are solved and results discussed. The annual and cumulative natural uranium requirements under these two scenarios are also calculated. Finally some conclusions are put forward based on the analyses.

Abstract The quasi-static compression, three-point bending and low-speed impact behavior of E690 high-strength steel lattice corrugated sandwich panels after corrosion in a marine environment were simulated by a non-linear finite element method. The uniform corrosion model was used to calculate the effects of different levels and duration of corrosion on the bearing capacity and energy absorption of an E690 panel. The results show that the corrosion of the outer panel has the least influence on the decrease of the mechanical properties; the structure’s mechanical properties are greatly reduced by the inner panel and core corrosion, and a new deformation pattern could be observed. Considering the influence of corrosion duration, the mechanical performance ranges from bad to good: outer+inner > inner > outer. Furthermore, the difference becomes more obvious with longer corrosion times, indicating that necessary corrosion protection measures should be taken to protect the panel from corrosion in marine environment, especially for the internal part of the panel.