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A PDE‐constrained model predictive control (MPC) algorithm for open‐channel systems based on the Saint‐Vevant(S‐V) equations is investigated in this paper. The S‐V equations, which precisely model the dynamics of open‐channel systems, are quasi‐linear hyperbolic partial differential equations (PDEs) without analytical solutions. Directly applying the S‐V equations to an MPC controller design becomes sophisticated. In this work, the calculus of variation is used to obtain the adjoint equations and the adjoint analysis method is utilized to deduce the gradients of the MPC optimization problem. Particularly, the physical constraints involving both the state and control variables are also considered. A gradient‐based optimization algorithm in combination with the numerical computation of Preissmann implicit scheme is proposed to solve the constrained MPC optimization problem. The control performances of the developed PDE‐constrained MPC algorithm with respect to the controlled water levels and gate openings are compared with those of the MPC controller designed for the linearized model. All the simulation tests are carried out on an aqueduct reach in Yehe Irrigation District in Hebei Province, China. The results show that the proposed PDE‐constrained MPC algorithm is a promising method in dealing with the constraints in terms of hyperbolic PDEs, control variables and state variables simultaneously. [ABSTRACT FROM AUTHOR]

Evaluating the water resources carrying capacity (WRCC) is the prerequisite and foundation for the planning and management of water resources. In this paper, according to risk theory, a framework for the risk assessment of WRCC was proposed based on the fragility of damage‐affected bodies and the damage posed by disaster‐inducing factors. Then, based on water quantity, water quality, water area, and water flow, a fragility index system was constructed from the water resources, economy, and society category. Additionally, the damage was analyzed in terms of climate change, urbanization, and industrialization. Finally, a model for the risk assessment of the WRCC was established by combining the fragility of the water resources carrying system with the compound damage posed by climate change, urbanization, and industrialization. The developed model was then applied to assess the risk of the WRCC in North China in 2017. The results indicate that the fragility of the WRCC was the highest in the Beijing–Tianjin–Hebei region, and the compound damage showed an increasing trend from the southeast to the northwest in North China. Meanwhile, the risk of the WRCC decreased from the southeast to the northwest, the highest risk was observed in Hebei Province, and the lowest risk was observed in Inner Mongolia. This research provides an important technical guideline for the sustainable utilization of water resources and the coordinated development of the economy and society. [ABSTRACT FROM AUTHOR]

An increasing number of emerging countries have begun implementing central environmental protection inspection (CEPI) to make up for the lack of environmental decentralization. Extant literature has shown that CEPI improves local environmental enforcement and performance. However, it is unclear whether CEPI, which is regarded as a non‐routine environmental enforcement and independent of the system of environmental decentralization, has an increasing effect on firms' environmental disclosure. This paper selects the listed firms located in Hebei Province, the pilot province inspected by the CEPI, as the treatment group and uses the listed firms of the third and fourth rounds of inspected provinces as the control group. The difference‐in‐difference results show that the environmental information level and quality of listed firms in Hebei Province is improved compared with those of firms in other provinces, and the increasing effect is more significant in state‐owned firms, in developed regions and in regions where local officials have more promotion incentives. The results of this study suggest that the central government should establish a regular environmental inspection mechanism and coordinate it with the system of environmental decentralization in emerging countries. [ABSTRACT FROM AUTHOR]

Multiregion input–output (MRIO) models have become increasingly important in economic and environmental analysis. However, the current resolution of most MRIO models fails to capture the heterogeneity between subregions, especially in cities. The lack of city‐level MRIO tables has impeded the accomplishment of city‐level studies and hampered the understanding of the relationship between urban growth and consumption, and teleconnections to other regions. In this paper, we propose a partial survey‐based multiple‐layer framework for MRIO table compilation of a Chinese province that distinguishes city‐based regions. This framework can effectively address a large number of data processes and retain consistency between layers. Using the framework, we first compile a nested Hebei‐China city‐level MRIO table and then apply city‐level energy footprint accounting of the North China urban agglomeration. Our results present the critical role of Hebei cities in energy supply in 2012 and quantify energy use embodied in goods for the domestic trade. Tangshan, Shijiazhuang, and Handan are distinctive cities in the energy supply chain of other regions, for both less developed and developed regions. This multiple‐layer framework represents a feasible approach for developing subregional‐level MRIO models and offers the possibility to analyze global trade at the subregional level with limited data. The data and results from the analysis in this article are available for download from China Emission Accounts and Datasets. [ABSTRACT FROM AUTHOR]

ABSTRACT This paper introduces a new way of decomposing regional inequality. It divides the Beijing-Tianjin-Hebei metropolitan region into three sets of districts in terms of the urban-rural resource flows: urban, peri-urban, and peripheral areas. Unlike the administrative divisions, these three sets of districts show how resource flows and agglomerates at the regional level. The paper decomposes regional inequality according to the three sets of districts. The paper's findings show that regional inequality decreased between 1990 and 1994, after which it remained steady. The study, for the first time, brings peri-urban areas into a regional decomposition analysis, and contributes to the understanding of urban-rural resource flows and inequality changes at the regional level. [ABSTRACT FROM AUTHOR]

The complexity of alluvial-pluvial fan depositional systems makes the detailed characterization of their heterogeneity difficult, yet such a detailed characterization is commonly needed for construction of reliable groundwater models. Traditional models mainly focus on using a single aquifer property to qualitatively or semi-quantitatively characterize the heterogeneity of aquifer, so that they are unable to quantitatively reflect the synthetic heterogeneity of all aquifer properties. In this paper, we propose the heterogeneity synthetic index (HSI) for quantitative characterization of synthetic heterogeneity of an aquifer. The proposed calculation process involves four steps: (1) estimation of the hydraulic conductivity of a sediment sample using the cloud-Markov model, (2) establishment of the sedimentary microfacies distribution model through the Markov chain, (3) characterization of the distribution model of hydrogeological parameters using the improved sequential simulation method according to the 'facies-controlled modeling' technique, and (4) application of the entropy weight method to calculate the weight coefficient of the above aquifer properties. The HSI of an aquifer is calculated by superposition of these models according to the corresponding weight coefficient. This approach was applied to the Luancheng aquifer deposit in the southeast Hutuo River alluvial-pluvial fan in the North China Plain (NCP). The results have demonstrated that aquifer 3 which was formed in the middle Pleistocene has the strongest heterogeneity, with an HSI of 0.25-0.75. Aquifer 4 formed in the early Pleistocene shows an intermediate heterogeneity, with the HSI ranging 0.35-0.75. The weakest heterogeneity was found in aquifers 1 and 2 formed in the Holocene and late Pleistocene, with HSI values of 0.40-0.75 and 0.40-0.80, respectively. The heterogeneity of all the four aquifers is relatively strong in the radial direction of the Huai River alluvial-pluvial fan due to the abrupt change of microfacies. In contrast, in the radial direction of the Hutuo River alluvial-pluvial fan, the microfacies change mildly, and the continuity of hydrogeological parameters is better, which has resulted in weaker heterogeneity of the four aquifers in this direction. Findings suggest that the sedimentary environment has significant effects on the aquifer heterogeneity. Considering that there arc many aquifer properties, HSI can quantitatively characterize the synthetic heterogeneity of the aquifer and describe the influence of each aquifer property on the synthetic heterogeneity of the aquifer according to its weight coefficient. Thus the HSI approach can be successfully used to deal with the spatial heterogeneity of aquifer and provide a foundation for studies on contaminant transport. [ABSTRACT FROM AUTHOR]

The Mesozoic family Mesopsychidae Tillyard, 1917 presently consists of seven described genera and 13 species from the mid-Triassic to the Early Cretaceous of Australia, South Africa and Eurasia. In the present paper one new genus and three new species of fossil mesopsychids are described that add significant distributional and stratigraphic extensions to the family. This finding documents the first formal record of fossil Mesopsychidae in China. Both Lichnomesopsyche gloriae gen. et sp. nov. and L. daohugouensis gen. et sp. nov. were found from the Middle Jurassic Jiulongshan Formation of Inner Mongolia, whereas Vitimopsyche kozlovi sp. nov., of mid Early Cretaceous age, was collected from the Jehol Biota of northern Hebei Province. This new, well-preserved material from China reveals complete and previously unknown body features, including head, antennae, mouthparts, legs and abdomen. The delicate and long proboscides of these new taxa indicate that they were feeding on externally exposed, nutrient-rich fluids of gymnospermous ovulate fructifications, and incapable of piercing surface epidermis - attributable principally to the absence of stylets. These proboscides originated, perhaps multiply, among basal Mecoptera and are functionally and structurally convergent with equivalent mouthparts borne by fossil and extant Diptera, Lepidoptera, Neuroptera and Coleoptera. [ABSTRACT FROM AUTHOR]

The article focuses on a research paper discussing the geological characteristics and genetic analysis of the Zhijiazhuang iron deposit in Laiyuan County in Hebei Province, China. It discusses the mineralogical analysis of magnetite and geochemical analysis of stable isotopes of hydrogen, oxygen, carbon and sulfur. It also suggests that the ore-forming fluid sourced from the deep earth, showing the characteristics of magmatic sulfur or the sulfur of mantle source.