bluuebunny/crossref_metadata_2025_split huggingface dataset:
Trend analysis on temperature and precipitation over North China Plain for past five decades
Authors: Yang Yan , Tang Shinan , Yu Lili , Chen Fei , Ding Yueyuan , Zhang Peize 
Published: March 2021

Abstract
The trend of change in temperature and precipitation in North China Plain over past few decades was examined using the non-parametric Mann-Kendall test in this paper. For the temperature part, a significant positive trend in annual temperature (0.03 °C/year) and a non-significant negative trend in annual precipitation (-0.67 mm/year) are found over the North China Plain (NCP) from 1960 to 2009. Furthermore, the winter temperature change and summer precipitation are found to be the most important factors for annual temperature and precipitation change. The winter temperature increases 0.04°C per year. As for the summer precipitation, it increases by 11% to the south of the Yellow River, over the NCP, and decreases by 20% to the north from 2000-2009 compared to 1990-1999. The reveal of the changing pattern in precipitation is a good start for us to further understand the main driving force of these changes and make a forecast on that.
Degradation of azo dye wastewater by the combination process of 3D BER and CW-MFC
Authors: Qiu Dengfei , Liu Shentan 
Published: March 2021

Abstract
The treatment of azo dye wastewater has become a hot issue in the area of water pollution control. In this paper, a novel combined process of constructed wetland-microbial fuel cell (CW-MFC) and three dimensional biofilm electrode reactor (3D BER) was carried out for treatment of reactive brilliant red X-3B dye wastewater. Decolorization rate, COD removal and electricity generation in the combination process were studied, and the main factors affecting the system’s performance were also investigated. The results showed that the decolorization rate of combination process (3D BER-CW-MFC) was over 96%, and closed-circuit CW-MFC had better decolorization effect than open-circuit CW-MFC. COD removal rate of the combination process was far higher than the 3D BER and CW-MFC operated alone (78.9%∼90.8% and 50.6%∼66.2%, respectively). With the increase of influent dye concentration in the 3D BER, Cell voltages of the CW-MFCs all increased firstly and then decreased. The cell voltage reached the maximum at influent dye concentration of 600 mg L-1, and then decreased by 6.42%∼14.34% after the dye concentration increased to 1000 mg L-1. In addition, cell voltage could be enhanced by increasing the cathode area of CW-MFCs, due to improved cathode potential and reduced total internal resistance of the system.
Ground deformation of Dongsheng mining area revealed by multi-temporal InSAR
Authors: Yang Qing , Chang Zhanqiang , Wang Yanqiao , Zhang Yanxin , Huang Songbo 
Published: March 2021

Abstract
Coal is one of the most important mineral resources in the industrial development of China. In order to minimize the losses directly or indirectly caused by the ground subsidence, it is necessary to accurately retrieve the information of the ground subsidence distribution during the mining process and make the accurate impact assessment of changes in the ecological environment. In this paper, we selected Sentinel-1A data of 22 scenes from July 2018 to March 2019, which covers Dongsheng coalfield of Ordos, Inner Mongolia. Then, PS-InSAR is used to obtain the ground deformation information. The results show that the PSs with high deformation rate and large accumulation are mainly located in the centre of the focused area, where the velocity along line of sight (LOS) mainly ranges from - 17 mm/year to - 5 mm/year with the extreme value reaching - 33.5 mm/year. Meanwhile the deformation rate of the majority of the PSs ranges from - 5 mm/year to 5 mm/year. It is highly recommended to reduce the ground deformation and mitigate the impact of land subsidence on the ecological environment caused by mining through programming logical mining schemes.
Valuing the ecosystem service losses from land reclamation by contingent valuation in Zhoushan, China
Authors: Wang Yingchun , Zhao Sheng 
Published: March 2021

Abstract

The process of formulating reclamation strategies is a complex and multi-disciplinary process. In life, the characteristic of relevant policy formulation is the lack of information related to the economic value of ecosystem services, which involves the consequences of losses caused by land reclamation. This article presents a present in order to introduce a willingness to pay (WTP) valuation method based on an easy-to-understand questionnaire for the loss of ecosystem services. A sample of 750 residents chooses and uses a hypothetical open payment card question, the purpose is to ask the interviewee WTP to be interviewed face to face. The results showed that the respondents, overall 88.7%, produced a positive WTP (WTP>0), while the average WTP was 362.19 yuan (RMB) per household year.
Solar dimming or brightening in the upper reaches of the Yangtze River Basin under 1.5 °C and 2 °C global warming targets?
Authors: Wang Zhiguo , Zhao Na , Hou Zhongrun 
Published: March 2021

Abstract
Solar radiation, as the primary energy source of the Earth, influences the climate conditions and changes of our planet. Whether solar dimming or brightening would occur in the future under 1.5 °C and 2 °C global warming background was an important question. In this study, climate data under four Representative Concentration Pathway (RCP) scenarios were used to calculate and analyse temporal and spatial changes of solar radiation in the upper reaches of the Yangtze River Basin for the future period 2020-2099. Results showed that surface solar radiation would increase under RCP2.6 and RCP4.5, while it would decrease under RCP6.0 and RCP8.5. Especially, dramatic solar dimming would occur in all years in the future under RCP8.5, which indicated that the fluctuations of the amount of solar energy in the future were related to the emission scenarios. Spatially, under global warming 1.5 °C, solar brightening would occur mainly in the central regions and become weaker with the higher emission scenarios. However, under global warming 2 °C, solar dimming would occur mainly in the upper Jinsha River Basin and the lower reaches of the Jialing River Basin and become stronger with the higher emission scenarios. Relative to the other three RCP, obvious and dramatic solar dimming would occur under RCP8.5 in the total area.
Study on the influence of key parameters of exterior window structure on building energy saving effect
Authors: Zhu Mengting , Diao Rongdan , Fu Jingjie , Jiang Xiufang , Zhang Ying 
Published: March 2021

Abstract
On account of the problem which was related to the negative effect of exterior windows energy saving in current residence building, we constructed a single energy-saving building with same structure and different exterior windows. Meanwhile, taking indoor temperature field and building energy consumption as entry points, the key parameters of the energy saving effect of the exterior window were compared and analyzed to study the indoor temperature field and the building thermal load and cooling load in the heating, cooling and transition season of energy-saving buildings which had exterior window structures (standard external windows, blue heat-absorbing glass windows, thermal reflection glass with high light transmission, ordinary hollow glass windows, low-E insulating glazing units, low-E high through glass windows, ordinary 3mm glass windows) with different window frames under the same climate environment. In addition, the grey theory and regression analysis were used to get the correlation degree and matrix equation between the energy-saving effect (the indoor temperature in heating season, the indoor temperature in refrigeration season, the indoor temperature in transition season, the annual cumulative heat load index, the annual cumulative cooling load index, the heating season heat load index, the air-conditioning season cooling load index) and key parameters (the glass thickness, the air layer thickness, the glass layer number, the heat transfer coefficient, the solar heat gain coefficient, the shading coefficient, the solar transmittance, the solar reflectance, the visible light transmittance, the visible light reflectance) in energy-saving buildings.
Study on the ground settlement during reclamation of Xiamen airport
Authors: Liu Guangqing , Liu Haiwang , Liu Zhiyong , Tu Yuan , Wang Kuihua 
Published: March 2021

Abstract
The settlement of soft soil foundation is a critical problem for the airport construction in coastal area. In order to study the long-term settlement characteristics of soft soil foundation of a Chinese reclamation airport (Xiamen Airport), this paper analyzed the monitoring settlement development of different regions in two runways to be built. The relationship between the total settlement from January 11, 2019 to May 22, 2020 and the thickness of soft soil was studied for guiding the settlement prediction of subsequent construction. The results showed that the development law of foundation settlement with different preloading durations under the same thickness of soft soil is different. As the preloading duration increases, the total settlement in the same period becomes smaller. Besides, the total settlement of Runway 2 increases approximately linearly with the thickness of soft soil (silt soil). However, the total settlement of Runway 1 under different thickness of soft soil is similar, which probably indicates primary consolidation has basically completed in this region. The research results in this paper is useful to understanding the settlement characteristics of Xiamen Airport, and can be used to analyse the settlement characteristics of other similar reclamation airports.
The design of energy-saving intelligent escape clothes hanger device
Authors: Guo Yaqin , Liu Qixiang , Ao Xiang , Feng Yaohui , Ji Gufei 
Published: March 2021

Abstract
Due to the rapid development of economy and technology, floor molding of modern building are different, interior and exterior circuit design are more complex. Therefore, the fire also increases sharply, causing huge losses to the national economy and people’s life safety. The survival rate of personnel in serious fires has become the focus of the whole society. We take the clothes hanger as the research object in the paper, refit the clothes hanger, and provides an intelligent escape device to speed up the escape time. The device mainly includes Single-Chip Microprocessor control module, communication module, detection module, alarm module and solar panel module. The device has simple structure and convenient installation, which solves the timeliness of personnel escape in the fire and avoids secondary casualties in the fire.
Reactive power compensation optimization configuration method to reduce the risk of multi-circuit DC commutation failure
Authors: Yuan Hangtao , Xie Xiangpeng , Zhou Xia , Zheng Chenyi 
Published: March 2021

Abstract
Aiming at the risk of simultaneous commutation failure of multiple DCs in multi-infeed DC areas, a reactive power compensation optimization configuration method to reduce the risk of multiple DC commutation failures is proposed, and the type, location and capacity of reactive power compensation devices are configured. Firstly, the type of reactive power compensation devices is determined by comparing SVC and STATCOM simulation; Secondly, the weak voltage area through typical faults in multi-infeed DC areas is found, and then the best reactive power compensation site is determined according to the concept of node relative transient voltage drop area RTVDAI index; The aim is to reduce the effect index of commutation failure risk and project economy, the best installation plan is determined by controlling the investment cost and reducing the risk of commutation failure. The closeness in the entropy method is used to evaluate the advantages and disadvantages of each capacity configuration plan, and then CFTOOL toolbox in MATLAB is used to fit the comprehensive analysis index of nearness. The optimal installation capacity is determined by analyzing the fitting curve of the closeness comprehensive analysis index. Finally, the engineering applicability of the configuration scheme was verified through simulation.
Windturbine blade fault diagnosis based on MFCC feature optimization strategy
Authors: Wang Yuxing , Tan Jianxin , Qin Xiaoliang , Hu Zhanfei , Jing Yanwei , Han Guidong 
Published: March 2021

Abstract
The fault problem of windturbine blades cannot be ignored. This paper proposes a fault diagnosis method for windturbine blades based on feature optimization strategy. First, the Mel-frequency cepstrum coefficient(MFCC) method is used to extract the feature samples of the windturbine sound signal, and then the entropy weight method is used to optimize the characteristics of the feature samples, and finally the K-means clustering is combined to realize the fault diagnosis of the windturbine blade. The effectiveness of the proposed method is verified by using two faulty windturbine and one faultless windturbine in a wind farm.
Analytic of VSC-HVDC Interconnected Power Systems from a Perspective of Frequency Security
Authors: Zhu Liuzhu , Ma Jing , Xu Jiayin , Shen Yuming , Zhang Enhui , Luo Xuzhi , Mao Fubin , Wang Lijun , Xia Kai , Yang Mengmeng 
Published: March 2021

Abstract
In the interconnected power systems with VSC-HVDC (Voltage Source Converter-High Voltage Direct Current) transmission links, the failures of VSC-HVDC system can cause large power imbalance for both sending-end and receiving-end power systems. In this paper, the reliability model of the VSC-HVDC system is developed based on series-parallel structure recognition. The frequency dynamics of the power systems are characterized considering the frequency regulation of the power systems in response to the power imbalance arise from the component failures. Moreover, the Monte Carlo simulation method is applied to analyze the frequency dynamics in different contingencies. The indices measuring the frequency stability and the reliability of the interconnected power systems are introduced.
Research on optimization of primary frequency regulation of thermal power units based on multi-model predictive control
Authors: Gao Aimin , Cui Xiaobo , Yu Guoqiang , Shu Jianjun , Yang Xiaolong , Zhang Tianhai 
Published: March 2021

Abstract
The nonlinear problem of system cannot be well solved using traditional power regulation system, which causes regulation lag and insufficient output and poor accuracy of the actual performance of the primary frequency regulation (PFR) on thermal power units. In order to further improve PFR performance of thermal power units, a multi-model predictive control method is adopted to optimize and improve the traditional steam turbine power control system. A PFR optimal control strategy is proposed, which improves the regulation performance and robustness of the power control system. The simulation results show that the proposed optimization algorithm can overcome the nonlinear problem of the steam turbine governing valve, and the regulating process is stable and fast without overshoot. This research is of great significance to improve the contribution rate of PFR of thermal power units and to better satisfy the assessment of power grid PFR, thereby to stabilize the frequency of power grid.
Research on factors and performance of solar thermoelectric radiant window
Authors: Zhang Jiajun , Zhang Wenjie , Huang Fengcheng , Zhao Yuqiang , Zhong Yongheng 
Published: March 2021

Abstract
Building energy consumption for cooling in hot climates accounts for about 70%- 80% of the total energy consumption. It’s interesting that offsetting the energy consumption by the development of new technology. A model of solar thermoelectric radiation window proposed in this paper, combining the concepts of photovoltaic (PV) power generation, thermoelectric cooling and radiant cooling, built a new model of heat transfer about the solar thermoelectric radiation windows. The new structure actively generates electricity for the consumption of cooling by PV module, while passively blocks part of solar radiation for reducing indoor load. Based on the distribution of thermoelectric cooling mode (TEM), the size of the radiator, the form of heat dissipation and other influencing factors, the relationship between the heat gain and cooling capacity, and the balance between power generation and power consumption of the new structure were analysed. The value of this research is to provide a certain reference value for the practical application of the solar thermoelectric radiation window.
Modeling technology of large-scale half speed unit and its thermal actuator participating in grid frequency modulation
Authors: Wen Libin 
Published: March 2021

Abstract
In view of the shortage of the technology of large half speed units in nuclear power participating in the primary frequency regulation modeling and parameter measurement of power grid, the speed regulation system, thermal actuator and prime mover model of nuclear power unit are established. At the same time, the technology of model parameter test, identification and verification is developed. The developed technology meets the requirements of BPA. Through the frequency step simulation of the established model and the obtained model parameters, and compared with the field test results, the results show that the model and its parameter test method are correct. The established model and its parameters can accurately reflect the dynamic process of nuclear motor group participating in the primary frequency modulation of large power grid.
Experimental study on the effect of blade surface roughness on aerodynamic performance
Authors: Gong Shuguang , Cao Hongyuan , Zhang Jianping , Lu Haishan 
Published: March 2021

Abstract
In order to study the effect of surface roughness of wind turbine blade on aerodynamic performance, the three novel roughness models are proposed, and the corresponding simulation model is also established. Simulation analysis and wind tunnel test are carried out respectively, and the results show that they are consistent with each other. The 5mm-spacing double rectangular roughness strips lead to 64.9% reduction of the maximum lift/drag, the single rectangular roughness strip pasted on 10% chord-length can reduce the maximum lift/drag by 30.8%, both two rectangular strip models can cause early stall, while the effect of arc strip is minimal among three roughness models.
A study on wavelet selection in power signal denoising
Authors: Gong Jing 
Published: March 2021

Abstract
In the wavelet threshold denoising of power signal, the selection of wavelet has an important influence on the denoising effect, and the wavelet generating function has diversity, if not selected properly, it will directly lead to the failure of denoising. Firstly, an operator is introduced to modify the threshold of each scale to better reflect the variation of wavelet coefficients of signal and noise with scale. Then a controllable threshold function is proposed to adapt to different soft and hard characteristics, and it is used to denoise the wavelet coefficients. Based on the study of the characteristics of wavelet, such as orthogonality, vanishing moment, support length and symmetry, four principles of wavelet selection in power signal denoising are proposed. The voltage sag and harmonics model are established, and db5, coif1 and sym2 wavelets are selected to decompose the signal to the fourth scale for denoising. The signal-to-noise ratio, mean square error and the detailed features of the reconstructed signal after denoising are compared. The experimental results show that the orthogonal wavelet db5 with high vanishing moment order and long support length has better denoising effect than coif1 and sym2, which proves the correctness of the wavelet selection principles proposed in this paper.
Game analysis of decreasing generation cost characteristics in electricity spot market
Authors: Lu Zhanhui , Jing Zhaoxia 
Published: March 2021

Abstract
The construction of Chinese electricity spot market is in its infancy. Market rules have borrowed from foreign mature market experiences, adopted marginal electricity price settlement mechanisms, and stipulated that the biddings on the power generation side will increase monotonously. However, there are thermal power generating units in China whose marginal cost does not meet the characteristics of monotonous increase. In this context, studying the strategic behaviour of thermal power generating units with diminishing marginal cost characteristics in the market, highlighting the impact of existing rules on market participants’ decision making, is of great significance to the design and operation of Chinese electricity spot market. First, an existing generation market clearing model based on monotonically increasing quotes and a strategy model for generating units based on monotonically decreasing marginal costs are established. Then, the above models are organically combined to form a bilevel optimization model, and the iterative optimization is performed to obtain a market equilibrium solution. Finally, a numerical example is used to clearly describe the bidding strategy of the unit in the spot market, and the incentive effects of market regulations on its bidding behaviour are discussed.
Fiscal and tax terms and economic evaluation methods for oil and gas projects in Abu Dhabi
Authors: Wang Keming , Zou Qian , Wang Zuoqian , Fang Lichun , Jiang Weina 
Published: March 2021

Abstract
The Middle East is the region with the lowest oil and gas production cost in the world and has always been the key area for investment by oil companies. With the large-scale bidding after the Iraq War, the number of bidding blocks provided annually in the Middle East has been greatly reduced, and the number of bidding blocks provided by the UAE government is relatively large. After the expiration of the existing contracts in 2014, the UAE government started block bidding and auction on a large scale, and offered favorable contract terms. The assets with great investment values attracted international oil giants. In this paper, based on the survey of bidding contracts of Abu Dhabi in recent years, fiscal and tax terms, demand markets, prices and costs to be focused on have been sorted out, an economic evaluation model for bidding blocks in Abu Dhabi has been established, and evaluation conclusions have been drawn through financial analysis and uncertainty analysis. Finally, the applicability of the economic evaluation analysis method and evaluation procedure has been verified through examples, so as to provide reference and enlightenment for international oil companies to participate in the new round of bidding of the UAE in the future.
Comparative analysis of actual and planned utilization hours of coal-fired power in China during the 13th Five-Year Plan
Authors: Cai Bin , Xue Yusheng , Wang Kui , Yang Mingyu , Zhang Hengxu , Zhu Lei , Zhao Dongming 
Published: March 2021

Abstract
Coal-fired power annual utilization hours (CPAUHs) is an important indicator to evaluate the utilization ratio of coal-fired power equipment (URCPE). In this paper, a comparison of actual and planned CPAUHs in China during the 13th Five-Year Plan is presented. The influences of power demand, installation capacity and electricity generation of non-coal-fired power and coal-fired power on CPAUHs are analyzed. It is pointed out that the overcapacity of coal-fired power is alleviated during the 13th Plan. Finally, the reposition of coal-fired power and the issue of CPAUHs during the 14th plan are discussed.