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Contemporary Chinese Law and Legal System is a rich source for teaching, study and research in Chinese law and legal system and a useful guide for legal practitioners who are engaged in international practices involving China. The book provides an in-depth overview of modern Chinese law and legal systems with a thorough analysis of basic legal infrastructure, civil code, and legal mechanisms of international civil litigation in Chinese courts and foreign arbitration in China. It includes the most recent judicial opinions and practices pertaining to implementing civil code and enforcing foreign arbitral awards and judgements. Detailed and comprehensive, Contemporary Chinese Law and Legal System provides profound knowledge about the law and legal infrastructure in modern China.
This Element provides a comprehensive guide to deep learning in quantitative trading, merging foundational theory with hands-on applications. It is organized into two parts. The first part introduces the fundamentals of financial time-series and supervised learning, exploring various network architectures, from feedforward to state-of-the-art. To ensure robustness and mitigate overfitting on complex real-world data, a complete workflow is presented, from initial data analysis to cross-validation techniques tailored to financial data. Building on this, the second part applies deep learning methods to a range of financial tasks. The authors demonstrate how deep learning models can enhance both time-series and cross-sectional momentum trading strategies, generate predictive signals, and be formulated as an end-to-end framework for portfolio optimization. Applications include a mixture of data from daily data to high-frequency microstructure data for a variety of asset classes. Throughout, they include illustrative code examples and provide a dedicated GitHub repository with detailed implementations.
In contrast to the drastic shifts in China's political landscape and society since 2012, taxation may appear as a comparatively mundane topic receiving limited attention. However, the relative stability in China's taxation system underscores its delicate role in maintaining a balance in state–society relations. The Element embarks on an exploration of China's intricate taxation system in the contemporary era, illuminating its origins and the profound reverberations on state–society relations. It shows that China's reliance on indirect taxation stems from the legacies of transitioning from a planned economy to a market-driven one as well as elaborate fiscal bargaining between the central and local governments. This strategy inadvertently heightens Chinese citizens' sensitivity to direct taxation and engenders the tragedy of the commons, leading to rising government debts and collusion by local governments and businesses that results in land expropriation, labor disputes, and environmental degradation.
Discover the principles of wireless power transfer for unmanned aerial vehicles, from theoretical modelling to practical applications. This essential guide provides a complete technical perspective and hands-on experience. It combines in-depth theoretical models, such as T-models and M-models, with practical system design, including wireless charging system construction. It presents systematic solutions to real-world challenges in UAV wireless charging, such as mutual inductance disturbances and lightweight units. Providing the resources to tackle complex industry problems this book covers the latest technological insights including advanced control methods, such as PT-symmetric WPT system control schemes and charging range extension techniques. Ideal for professional engineers, designers, and researchers, it provides the tools needed to innovate in UAV technology and power systems. Whether you're developing new systems or optimizing existing ones, this comprehensive resource delivers the insights and techniques to drive progress in wireless power transfer for unmanned aircraft.
Higher levels of parental reflective functioning are associated with normatively developing children’s secure attachment and better socioemotional functioning. Children with autism spectrum disorder (ASD) exhibit more severe behavioral problems than normatively developing children, which hinder social adaptation and impose significant parenting challenges. However, the relationship between parental reflective functioning and behavioral problems in children with ASD remains underexplored, with most studies being cross-sectional. The present study examined reciprocal associations between parental reflective functioning and behavioral problems over a 6-month period across three timepoints in a sample of 180 Chinese parents of children with ASD using cross-lagged panel analyses. The result revealed a bidirectional relationship between parental reflective functioning and children’s internalizing behavioral problems. Higher level of pre-mentalizing predicted increased internalizing behavioral problems at the subsequent time point, and vice versa. A child-driven effect was found in the association between externalizing behavioral problems and parental reflective functioning. A higher level of children’s externalizing behaviors was correlated with increased parental pre-mentalizing and decreased certainty about mental states, as well as reduced parental interest and curiosity, at subsequent time points. The results underscore the importance of developing parenting interventions aimed at enhancing parental reflective functioning to mitigate behavioral problems in children with ASD.
Understanding high-variability speech is particularly challenging for second-language (L2) learners due to difficulties with extrinsic normalization, a perceptual strategy utilizing contextual cues to overcome speech variability. This study investigates the neural correlates of these difficulties among Mandarin speakers learning Cantonese, using EEG. Behaviorally, Mandarin learners demonstrated a significant yet considerably reduced ability to normalize Cantonese tone variability with contexts compared to native Cantonese speakers. EEG analysis showed that while native speakers engage multiple neural components (N1, P2, and LPC) for acoustic, phonetic/phonological, and cognitive adjustments in extrinsic normalization, Mandarin learners only activated P2, focusing on phonetic/phonological adjustments. This discrepancy underscores the multi-faceted nature of successful extrinsic normalization, which L2 learners fail to fully engage. L2 immersion significantly improves extrinsic normalization, particularly at the cognitive-adjustment stage. Overall, this study illuminates the intricate nature of poor extrinsic normalization in L2 learners and the importance of L2 immersion for effective L2 speech perception.
Several million years of natural evolution have endowed marine animals with high flexibility and mobility. A key factor in this achievement is their ability to modulate stiffness during swimming. However, an unresolved puzzle remains regarding how muscles modulate stiffness, and the implications of this capability for achieving high swimming efficiency. Inspired by this, we proposed a self-propulsor model that employs a parabolic stiffness-tuning strategy, emulating the muscle tensioning observed in biological counterparts. Furthermore, efforts have been directed towards developing the nonlinear vortex sheet method, specifically designed to address nonlinear fluid–structure coupling problems. This work aims to analyse how and why nonlinear tunable stiffness influences swimming performance. Numerical results demonstrate that swimmers with nonlinear tunable stiffness can double their speed and efficiency across nearly the entire frequency range. Additionally, our findings reveal that high-efficiency biomimetic propulsion originates from snap-through instability, which facilitates the emergence of quasi-quadrilateral swimming patterns and enhances vortex strength. Moreover, this study examines the influence of nonlinear stiffness on swimming performance, providing valuable insights into the optimisation of next-generation, high-performance, fish-inspired robotic systems.
Kinematically redundant parallel mechanisms (PMs) have attracted extensive attention from researchers due to their advantages in avoiding singular configurations and expanding the reachable workspace. However, kinematic redundancy introduces multiple inverse kinematics solutions, leading to uncertainty in the mechanism’s motion state. Therefore, this article proposes a method to optimize the inverse kinematics solutions based on motion/force transmission performance. By dividing the kinematically redundant PM into hierarchical levels and decomposing the redundancy, the transmission wrench screw systems of general redundant limbs and closed-loop redundant limbs are obtained. Then, input, output, and local transmission indices are calculated, respectively, to evaluate the motion/force transmission performance of such mechanisms. To address the problem of multiple inverse kinematics solutions, the local optimal transmission index is employed as a criterion to select the optimal motion/force transmission solution corresponding to a specific pose of the moving platform. By comparing performance atlas before and after optimization, it is demonstrated that the optimized inverse kinematics solutions enlarge the reachable workspace and significantly improve the motion/force transmission performance of the mechanism.
Global Navigation Satellite System (GNSS) positioning accuracy is challenged due to abnormal signals in harsh environments. This study proposes an approach for multiple and mixed abnormal measurement processing in multi-GNSS positioning and navigation based on the resilient a priori innovation and posterior residual (PR) for harsh environments. Specifically, first, both static and kinematic processing modes are considered when calculating the innovation vector (IV). Second, observations are classified and abnormal measurements are eliminated based on the different observation accuracies of different GNSS systems within the resilient IV method. Finally, the resilient PR method considers the total number of redundant observations. Compared with the traditional IV and PR method, the RIP method improves the positioning accuracy by approximately 30.2% and 58.0% in static experimental datasets No. 1 and No. 2, respectively. In the kinematic experiment, it improves the ambiguity success rate and positioning accuracy by approximately 41.5% and 86.7%, respectively.
Weeds significantly reduce sugarcane (Saccharum officinarum L.) production by 30% to 50% and cause complete crop loss in severe cases. Guangxi, a central sugarcane-growing region in southern China, faces significant challenges due to the proliferation of weeds severely impacting crop tillering, yield, and quality. In this study, we surveyed and identified 35 weed species belonging to 16 families in Longzhou, Nongqin, and Qufeng, with significant threats posed by purple nutsedge (Cyperus rotundus L.), bermudagrass [Cynodon dactylon (L.) Pers.], hairy crabgrass [Digitaria sanguinalis (L.) Scop.], black nightshade (Solanum nigrum L.), white-edge morningglory [Ipomoea nil (L.) Roth], and ivy woodrose [Merremia hederacea (Burm. f.) Hallier f.]. The application of 81% MCPA-ametryn-diuron achieved greater than 90% control within 15 d. Although herbicides are effective, they can unintentionally harm sugarcane, indicating a need for tolerant genotypes. Therefore, we comprehensively evaluated herbicide-induced phytotoxic responses and identified tolerant sugarcane genotypes over 3 yr of trials conducted on 222 genotypes across Guangxi. We quantified phytotoxicity by counting the number and severity of affected leaves. The ANOVA revealed statistically significant main and interaction effects among genotype, crop cycle, and location. Cluster and discriminant analyses classified the genotypes into five groups: 21 highly tolerant (HT), 68 tolerant, 75 moderately tolerant, 18 susceptible, and 40 highly susceptible. The 21 HT genotypes demonstrated strong potential to be used as parental lines for breeding herbicide-tolerant varieties, to inform precision breeding strategies, and to increase tolerance to herbicide stress in sugarcane.
For each $n\geq 1$, let $FT_n$ be the free tree monoid of rank n and $E_n$ the full extensive transformation monoid over the finite chain $\{1, 2, \ldots , n\}$. It is shown that the monoids $FT_n$ and $E_{n+1}$ satisfy the same identities. Therefore, $FT_n$ is finitely based if and only if $n\leq 3$.
To address the global climate crisis, it is urgent to achieve carbon neutrality by the mid-21st century, balancing carbon emissions and carbon absorption from the atmosphere. This study examines the current advancements in biological methods for capturing carbon dioxide (CO2) in response to global climate change, emphasizing the importance of sequestering CO2 through biological carbon capture and utilization. First, we present an overview of typical carbon capture methods, including geological and oceanic carbon storage. We then highlight the significance of utilizing photosynthetic organisms, such as plants, algae and microorganisms, for carbon capture and sequestration. We also analyze the role of photosynthesis in carbon capture and explore the potential of microbial carbon capture, examining the impact of environmental factors on capture efficiency. Additionally, we discuss the development of symbiotic approaches to enhance carbon fixation capacity. Finally, this review provides key insights into the challenges and future directions in advancing the field of biological carbon capture to achieve carbon neutrality.
From the near-Earth solar wind to the intracluster medium of galaxy clusters, collisionless, high-beta, magnetized plasmas pervade our universe. Energy and momentum transport from large-scale fields and flows to small-scale motions of plasma particles is ubiquitous in these systems, but a full picture of the underlying physical mechanisms remains elusive. The transfer is often mediated by a turbulent cascade of Alfvénic fluctuations as well as a variety of kinetic instabilities; these processes tend to be multi-scale and/or multi-dimensional, which makes them difficult to study using spacecraft missions and numerical simulations alone. Meanwhile, existing laboratory devices struggle to produce the collisionless, high ion beta ($\beta _i \gtrsim 1$), magnetized plasmas across the range of scales necessary to address these problems. As envisioned in recent community planning documents, it is therefore important to build a next generation laboratory facility to create a $\beta _i \gtrsim 1$, collisionless, magnetized plasma in the laboratory for the first time. A working group has been formed and is actively defining the necessary technical requirements to move the facility towards a construction-ready state. Recent progress includes the development of target parameters and diagnostic requirements as well as the identification of a need for source-target device geometry. As the working group is already leading to new synergies across the community, we anticipate a broad community of users funded by a variety of federal agencies (including National Aeronautics and Space Administration, Department of Energy and National Science Foundation) to make copious use of the future facility.
Submerged flexible aquatic vegetation exists widely in nature and achieves multiple functions mainly through fluid–structure interactions (FSIs). In this paper, the evolution of large-scale vortices above the vegetation canopy and its effect on flow and vegetation dynamics in a two-dimensional (2-D) laminar flow are investigated using numerical simulations under different bending rigidity $\gamma$ and gap distance d. According to the variation of large-scale vortex size and intensity, the evolution process is divided into four distinct zones in the streamwise direction, namely the ‘developing’ zone, ‘transition’ zone, ‘dissipation’ zone and ‘interaction’ zone, and different evolution sequences are further classified. In the ‘developing’ zone, the size and intensity of the large-scale vortex gradually increase along the array, while they decrease in the ‘dissipation’ zone. The supplement of vegetation oscillating vortices to large-scale vortices is the key to the enhancement of the latter. The most obvious dissipation of large-scale vortices occurs in the ‘transition’ zone, where the position of the large-scale vortex is significantly uplifted. The effects of $\gamma$ and d on the evolution of the large-scale vortex are discussed. In general, the features of vegetation swaying vary synchronously with those of large-scale vortices. The flow above the canopy is dominated by large-scale vortices, and the development of flow characteristics such as time-averaged velocity profile and Reynolds stress are closely related to the evolution of large-scale vortices. The flow inside the canopy, however, is mainly affected by the vortex shed by the vegetation oscillation, which leads to the emergence of negative time-averaged velocity and negative Reynolds stress.
Mercier’s criterion is typically enforced as a hard operational limit in stellarator design. At the same time, past experimental and numerical studies have shown that this limit may often be surpassed, though the exact mechanism behind this nonlinear stability is not well understood. This work aims to contribute to our current understanding by comparing the nonlinear evolution of Mercier unstable Wendelstein stellarators with that of nonlinearly stable quasi-interchange modes in tokamaks. A high mirror, very low $\iota$, W7-X-like configuration is first simulated. Broad flow structures are observed, which produce a similar magnetohydrodynamic (MHD) dynamo term to that in hybrid tokamak discharges, leading to flux pumping. Unlike in tokamaks, there is no net toroidal current to counterbalance this dynamo, and it is unclear if it can be sustained to obtain a similar quasistationary nonlinear state. In the simulation, partial reconnection induced by the overlap of multiple interchange instabilities leads to a core temperature crash. A second case is then considered using experimental reconstructions of intermediate $\beta$ W7-AS discharges, where saturated low-n modes were observed experimentally, with sustained MHD signatures over tens of milliseconds. It is shown that these modes do not saturate in a benign quasistationary way in current simulations even in the presence of background equilibrium $\boldsymbol{E} \times \boldsymbol{B}$ flow shear. This leads to a burst of MHD behaviour, inconsistent with the sustained MHD signatures in the experiment. Nevertheless, the (1, 2) mode is observed at the experimental Spitzer resistivity, and its induced anomalous transport can be overcome using an experimentally relevant heat source, reproducing these aspects of the dynamics. The possible reasons for the discrepancies between experiment and simulation, and the observation of partial reconnection in contrast to flux pumping are discussed, in view of reproducing and designing for operation of stellarators beyond the Mercier stability limit.
In gas evolving electrolysis, bubbles grow at electrodes due to a diffusive influx from oversaturation generated locally in the electrolyte by the electrode reaction. When considering electrodes of micrometre size resembling catalytic islands, direct numerical simulations show that bubbles may approach dynamic equilibrium states at which they neither grow nor shrink. These are found in undersaturated and saturated bulk electrolytes during both pinning and expanding wetting regimes of the bubbles. The equilibrium is based on the balance of local influx near the bubble foot and global outflux. To identify the parameter regions of bubble growth, dissolution and dynamic equilibrium by analytical means, we extend the solution of Zhang & Lohse (2023 J. Fluid Mech. vol. 975, R3) by taking into account modified gas fluxes across the bubble interface, which result from a non-uniform distribution of dissolved gas. The Damköhler numbers at equilibrium are found to range from small to intermediate values. Unlike pinned nanobubbles studied earlier, for micrometre-sized bubbles the Laplace pressure plays only a minor role. With respect to the stability of the dynamic equilibrium states, we extend the methodology of Lohse & Zhang (2015a Phys. Rev. E vol. 91, 031003(R)) by additionally taking into account the electrode reaction. Under contact line pinning, the equilibrium states are found to be stable for flat nanobubbles and for microbubbles in general. For unpinned bubbles, the equilibrium states are always stable. Finally, we draw conclusions on how to possibly enhance the efficiency of electrolysis.
The rapid development of generative artificial intelligence (AI) systems, particularly those fuelled by increasingly advanced large language models (LLMs), has raised concerns of their potential risks among policymakers globally. In July 2023, Chinese regulators enacted the Interim Measures for the Management of Generative AI Services (“the Measures”). The Measures aim to mitigate various risks associated with public-facing generative AI services, particularly those concerning content safety and security. At the same time, Chinese regulators are seeking the further development and application of such technology across diverse industries. Tensions between these policy objectives are reflected in the provisions of the Measures that entail different types of obligations on generative AI service providers. Such tensions present significant challenges for implementation of the regulation. As Beijing moves towards establishing a comprehensive legal framework for AI governance, legislators will need to further clarify and balance the responsibilities of diverse stakeholders.