Search

How to reasonably evaluate the performance of scientific research activities in universities has attracted people's extensive attention. This study identifies the scientific research activity of Chinese universities as a two-process system with three sub-stages, including technical accumulation and research commercialization processes. Where, the process of technical accumulation includes the production of scientific research and patenting stage, while the process of research commercialization is a separate stage. First, this study proposes a network DEA model with two processes and three sub-stages to evaluate and decompose the performance of scientific research activities in universities. Secondly, taking 61 Chinese universities in the "Double First-Class" initiative (DFIU) as examples, this study evaluates the overall efficiency, stage efficiency and coordination efficiency of scientific research activities in Chinese universities. The final main conclusions are as follows: (1) The average score associated with the transformation efficiency of scientific research achievements based on the internal structures is only 0.2406, lower than the CCR efficiency and merger efficiency, indicating that most universities are still facing problems such as low resource utilization efficiency or unsatisfactory results. (2) The universities in the "First-class Discipline" construction plan (UFDCP) have outstanding performance in the technical accumulation process and the production of scientific research stage. Professional characteristics universities are generally much less efficient than polytechnic universities and comprehensive universities. (3) The universities in the "First-class Discipline" construction plan (UFDCP) are better than the universities in the "First-class Universities" construction plan (UFUCP) in terms of average efficiency values and polytechnic universities are better than other types of universities in terms of average efficiency values. We can find part of the reason for this difference in average efficiency from the evaluation of coordination efficiency. • This paper analyses the internal structure and internal operating mechanisms of research activities in universities. • Constructed a two-process network model with three sub-stages as a method to deal with unique efficiency decompositions. • The coordination efficiency of university scientific research system is calculated. [ABSTRACT FROM AUTHOR]

[Display omitted] • A method for spatiotemporal coordination of multienergy systems is proposed. • Virtual energy storage gain is calculated based on spectral analysis. • The hydropower regulation ability affects the virtual energy storage gain. • The optimal coordination range between multiple energy sources is obtained. Utilizing the spatial heterogeneity and climate periodicity of various available renewable energy sources can enhance the multienergy complementarity, which will further reduce the energy storage demand and contributes to the "virtual energy storage gain." In this paper, we propose a spatiotemporal coordination method based on spectral analysis for a wind-PV-hydropower system that targets the maximum virtual energy storage gain. The complementary effect of hydropower on wind and PV power can be seen as changes in the regulation ability resulting from the hydropower construction development as well as a decreased variance in the total system production output. This method is used to determine the optimal coordination distance of multiple energy sources that are matched over different periods representing typical climate variation. A case study in the Yalong River basin in China obtains the best range of hydropower bundling surrounding wind power and PV power stations under different hydropower construction planning scenarios, and it reveals that increased regulation capacity of hydropower will reduce the optimal coordination distance but can achieve more energy balance if both actual storage and virtual storage is accounted for. This approach can realize energy delivery with the optimal coordination distance to meet intensive and efficient development needs, which can provide guidance and support for the planning and construction of wind-PV-hydropower storage systems. [ABSTRACT FROM AUTHOR]

As the global climate change and the rapid progress of urbanization, the frequent occurrence of flooding disasters and non-point source pollution seriously threaten the sustainable development of modern cities. To alleviate these problems, China started to pilot construction of the "Sponge City" (SPC). Over a decade, it has attracted public attention, supports, and participations. The paper presents a literature review of sponge city construction (SPCC) process (planning, design and construction) as well as the assessment of SPC, including: operation, maintenance, and effectiveness. Research gap and future works are also proposed. The paper offers some tactics for SPCC, including: 1) in the planning and construction stage of SPC, the goals and systematic plans should be formulated according to local water-environmental conditions. The drainage plan should cover the strategy to dispose runoff volumes at sources and the ultimately goal for flood mitigation. The drainage design involves the combination of various green and grey infrastructures; 2) It is important to identify monitoring methods and hydrological models which can be used to assess the performance of a SPC. With adequate field data, all models and methods should be calibrated for not only runoff quantity and quality control but also the alleviation of urban heat island effects, including the base flows and local groundwater table; 3) Based on the regional field data, it is necessary to standardize regional design parameters, construction material specifics, and maintenance scheme and schedule that would significantly affect the facility's infiltrating and filtering processes, therefore, a regular maintenance program should be initiated to monitor the operations of the as-built facilities according to local climate conditions. The paper evaluated several maintenance methods for ten typical facilities to provide a reference for the operation and maintenance of facilities in SPCC. • The sponge city construction (SPCC) and design methods were introduced in detail. • Scientific and reasonable assessment can better guide the SPCCs. • The sponge city (SPC) facilities can be a better way to control stormwater runoff. • Monitoring and simulation method are equally important for assessing SPC effect. • A maintenance program should be initiated to monitor the operations of SPC facility. [ABSTRACT FROM AUTHOR]

The paper offers a geographical interpretation of the evolving technical, political, and economic intricacy of large dams. It incorporates existing hydropolitical scholarship and the notion of the Chinese Water Machine to reframe dams as assemblages built by specific political, financial and technical processes in particular socioenvironmental regions. The paper examines the continuity of hydropolitical relationships through a genealogical inquiry into the formulation and materialisation of Ghana's three dams: the Akosombo and Kpong dams built during the Cold War, backed by Western lenders and engineering companies; and the Bui dam commissioned in the 2010s, with support from China. Based on fieldwork in Ghana and China, as well as documentary evidence, the paper argues that the thinking, planning and building of dams interconnect the host regime and external techno-financial actors with their floating political-economic interests, but in a durable way. Sometimes, even if little concrete is actually poured, the symbolic power of dams endures, transforms, and at certain times and places expands, through events and discourses of national and international interest groups pursuing their own purposes, albeit with the replacement of influential individuals and powerful institutions, and regardless of the involvement of Western, Chinese and/or other actors. Ruptures exist but do not necessarily break the continuity of dam assemblages. The emergence of an opposition assemblage that battles against dams is a more recent complexity. [ABSTRACT FROM AUTHOR]

[Display omitted] • Accurate assessment of China's ecological environment changes in the past 20 years is important. • We used time-series NDVI data (1998–2018) to evaluate China's ecological environment change. • In one-third of China the ecological environment has improved, and in 10%, the ecological environment has deteriorated. • The Yellow River Basin is an area where the ecological environment has significantly improved. • The main reason for the deterioration in the ecological environment of the eastern coastal areas is urban expansion. The ecological environment is the foundation of human survival and development. China's ecological environment has undergone a historic transition from partial improvement to overall improvement. In this paper, long time series NDVI data (1998–2018) are used to evaluate the ecological environment change and spatiotemporal change that has taken place in China over the last 20 years, at different scales (regional, provincial, county, and grid scales). Combined with typical areas, the causes of ecological environment change are revealed. The results show that in about one-third of China, the ecological environment improved, and in 10%, the ecological environment deteriorated. Ningxia, Shaanxi, Shanxi, Guizhou, and Guangxi are the provinces in which the improvement of the ecological environment is most pronounced. However, the ecological environments with vegetation as the core in Shanghai and Jiangsu Province have deteriorated significantly. The areas with the fastest improvement in their ecological environment are those with precipitation of 200–600 mm. The Yellow River Basin is an area where the ecological environment has significantly improved. Forestry projects and the development of oasis agriculture effectively promote the improvement of the ecological environment. In the past 20 years, the main reason for the degradation of the ecological environment in eastern coastal areas is urban expansion. China should continue to strengthen its overall layout of forestry projects and improve its ecological environment. When planning its ecological construction, China should fully consider the associated physical and geographical conditions, and adjust measures to local conditions accordingly. China should coordinate the relationship between development and protection and avoid the "pie spread" expansion witnessed in eastern coastal areas. [ABSTRACT FROM AUTHOR]

Since the beginning of 2020, the weak domestic power demand caused by the COVID-19 pandemic and the large-scale advancement of coal power construction projects may have further aggravated the coal power overcapacity in China. Given the new situation, this study collected the data on China's installed electricity capacity and electricity demand during the 13th Five-Year Plan period. Moreover, a reasonable capacity evaluation model of coal power was established based on the energy and electric power balance to analyze China's coal power overcapacity in 2019 and determine the reasonable capacity for 2025. The internal reasons of unreasonable energy structure and regional difference of energy structure are systematically discussed. Results show that the overcapacity in 2019 was approximately 170 GW, and the overcapacity situation in North, Northwest, and South China was particularly serious. The reasonable coal power capacity for 2025 under the basic situation is 950 GW, indicating that if all the coal power units under construction and planning are operated, the overcapacity in 2025 will be 300 GW. Sensitivity and comprehensive scenario analyses show that under different scenarios, the upper and lower limits of the reasonable coal power capacity in 2025 are 1083 and 794 GW, respectively. Finally, this paper proposes relevant policy recommendations to cope with China's serious coal power overcapacity problem. [Display omitted] • Capacity evaluation model of coal power is established. • Quantitative analysis is provided for each regional power grid of China. • The coal power overcapacity of China exceeds 170 GW in 2019. • The overcapacity situation may further deteriorate during the 14th FYP period. • A reasonable scale of coal power is 950–1000 GW at 2025. [ABSTRACT FROM AUTHOR]

This paper applies the extended MFDFA method to analyze the volatility characteristics, multifractal features and asymmetry in EU carbon emission permits trading market(EUA) and the main Chinese carbon emission permits market including HBEA, SZA and GDEA. We divided the EUA market into three stages according to the phased construction plan of European commission. The empirical analysis shows that the fluctuation in the second and third stage of EUA market presents a long-term memory feature. However, there is obvious anti-persistent characteristics in the volatility of three main Chinese carbon emission permits trading markets and the first stage in EUA market. The multifractal degree in three main Chinese carbon emission permits trading markets is less than that in the first stage of EUA market, but far greater than the second and third stages. We also verified that the HBEA market has the weakest volatility and the least multifractal degree among three Chinese markets, and whose validity is second to the third stage of EUA market. In addition, the fluctuation of the EU and Chinese carbon emission permits trading markets are asymmetric. The EUA market has stronger reaction to good news, while Chinese carbon emission permits trading market still displays the leverage effect which verifies the volatility is more sensitive to the bad news in the second and third stages. Therefore, the results powerfully demonstrate that the Chinese carbon emission permits trading market is less mature and highly dynamic, which is similar to the level of first stage of EUA market. The volatility in Chinese markets is strong, and exists much noise in the system. So, the efficiency in Chinese markets is weaker than EU. Chinese markets are still far from maturity and efficiency. • The market price volatility does not possess the significant long-term memory characteristics, it shows up the anti-persistent features. • With the development of the EUA market, the multifractal characteristics become weaker and weaker, and the reaction of the market price fluctuation to information become weaker as well. • The market asymmetry reflects the reaction of the price volatility to the positive and negative information. [ABSTRACT FROM AUTHOR]

District heating (DH) is rapidly expanding in China, which consumes a significant share of the national energy and aggravates pollution problems. Among the Northern provinces, Inner Mongolia Autonomous Region (IMAR) has a large area of district heating which relies heavily on coal boilers. In order to achieve the clean heating development goal, this paper first presents a detailed investigation and mapping of the clean heating resources at county levels in the IMAR. Combined with the different energy-saving strategies, four pathways for future DH were proposed. Considering the forecasted scenarios of DH for years 2025 and 2035, this study compares the proposed pathways in terms of primary energy consumption and economic benefits. It was observed that by replacing coal boilers with clean heating resources, the clean heating sources pathway could reduce coal consumption by about 41%, with 33% annual cost savings in 2018 compared with the reference pathway. However, when taking building renovation into account, the economically optimal renovation plan lies between the proposed SHRP and FHRP. The conclusions from this study provide valuable suggestions for clean heating developments in the IMAR and other parts of Northern China. • Clean heating resources in Inner Mongolia Autonomous Region are investigated and mapped in details. • 4 district heating pathways combining renovations in heating sources and buildings are proposed. • Heat demand for years 2025 and 2035 are forecasted. • Replacing coal boilers with clean heating resources can reducing both energy consumption and annual cost. • The economically optimal building renovation plan lie between the proposed pathways. [ABSTRACT FROM AUTHOR]