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Summary At present, mud pulse transmission is widely used in underground wireless transmission. To extract more accurately the original drilling fluid pulse signals while drilling, in this paper, we developed an algorithm for optimal denoising shaping based on particle-swarm-optimized time-varying filtering empirical mode decomposition (TVFEMD). The performance of TVFEMD heavily depends on its parameters (i.e., B-spline order and bandwidth threshold). In the traditional TVFEMD method, the parameters are given in advance and may not be optimized, so it is difficult to achieve satisfactory decomposition results. To tackle this issue, the correlation coefficient was used as the objective function, and the particle-swarm-optimization algorithm was used to optimize the parameters of TVFEMD in this paper. First, the particle swarm optimization was used to search for the best combination of parameters. Then, the TVFEMD was applied to obtain a series of intrinsic mode functions (IMFs). Subsequently, the optimal denoising and shaping algorithm was used to determine the best reconstructed signal by low-pass filtering. Permutation entropy was taken as the evaluation index to obtain a reconstruction signal. Finally, the reconstructed signal was processed by square wave shaping to obtain accurate drilling fluid pulse signals. The approximation of the algorithm is 0.7581, and relevance is as high as 0.8535. The simulation signal and drilling fluid pulse signal analysis results showed that the proposed approach can extract the original pulse signal accurately.

The irrigating winter wheat one or two times each season was practiced in Huanghuai Winter Wheat Region in order to reduce the over-exploitation of groundwater. In this study, plant height (PH) and its relationship with yield were analyzed in a field study conducted over three growing seasons with 102 wheat varieties irrigated zero to two times at different growth stages. Here, we found that irrigation at the jointing stage increased wheat PH by 6.60–9.70%. Whereas irrigation at the early milking stage had almost no effect on it. Against the wildtype alleles Rht-B1a and Rht-D1a, the genetic background of Rht-B1b and Rht-D1b significantly reduced PH by 14.40–15.50% and 16.90–19.10%, respectively. The combined Rht-B1b and Rht-D1b can reduce PH by 29.10–32.50%. PH was strongly, negatively correlated with grain yield in jointing irrigation (W1) or jointing + milking irrigation (W2) over three growing seasons. In contrast, a significant positive correlation was detected in no-irrigation (W0) in the 2012/2013 wheat growing season, yet no correlation was found in 2013/2014 and 2014/2015. PH was positively correlated with drought coefficient (DRC) in W1 and W2. These results augment our understanding of the relationship between PH and grain yield in different irrigation regimes and provide PH traits for wheat improvement on water saving.

Hybrid DC circuit breaker used in higher voltage flexible HVDC project is the current development trend. With the increase of the breaking current level of the DC circuit breaker, the magnetic field interference intensity of the surrounding secondary equipment is gradually enhanced. In this paper, the DC field of DingHai converter station of Zhoushan flexible DC transmission project is taken as the simulation object. Considering the commutation process of DC breaker breaking large current, the transient magnetic field interference value of the secondary equipment in the DC field is calculated when the bipolar short circuit occurs on the DC side. The results show that when the DC circuit breaker breaks the 15 kA current, the maximum value of the magnetic field interference of the secondary equipment near the positive and negative DC circuit breakers in the DC field are 700 A/m and 382 A/m, respectively. The peak value of the magnetic field interference can be included in the test level proposed in the electromagnetic compatibility standard "Test and Measurement Technology: Pulse Magnetic Field Immunity Test", but the duration time of the pulsed magnetic field waveform to be evaluated is recommended to be maintained at 3 ms.

Renewable energy (RE) development and the promotion of public participation in environmental decision-making are two growing initiatives worldwide. However, ineffective public participation in decision-making on RE projects (REPs) contributes to strong public opposition to proposed REPs. This has become a particularly important issue in China. This thesis aims to provide suggestions for Chinese legal reform of public participation in decision-making on REPs by drawing from the English experience. Drawing insight from the English experience is novel to this thesis. England provides useful lessons on implementing public participation, but none of the existing literature systematically examines the legal framework for public participation in decision-making on REPs in England and in China. This thesis addresses this gap and examines the public’s right to participate in decision-making in these jurisdictions. The thesis identifies the role of public participation in decision-making on REPs and identifies the related legislative issues under the Aarhus Convention, a multinational treaty on public participation. It discusses a critical issue — ‘Green on Green’ tension — arising in RE development and reveals the underlying factors contributing to this tension. The thesis systematically analyses the relevant requirements in English law and Chinese law. It also reviews the implementation issues in practice through an examination of case studies. The analysis in this thesis shows that Chinese law has improved regarding public participation in decision-making with respect to REPs. However, the thesis also demonstrates that the current legal framework still does not adequately address all the problems that can lead to ineffective public participation. In particular, the law does not address the scope of public participation, who can participate in public participation, what methods should be used to inform the public, the time-frame for public participation, what methods of consultation should be adopted, and how to deal with the outcome of public participation. This thesis critiques Chinese public participation law against English law which serves as a valuable benchmark and reference. It identifies principles for best practice based on a literature review and proposes suggestions for Chinese legal reform in an effort to improve the effectiveness of public participation in decision-making on REPs.