Concept and Practices Involved in Comprehensive River Control Based on the Synergy among Flood Control, Ecological Restoration, and Urban Development: A Case Study on a Valley Reach of Luanhe River in a Semiarid Region in North China

Many rivers in semiarid areas have ecological degradation and flood control problems that need to be addressed urgently. In order to maintain river health and to promote the sustainable development of cities near these rivers, a comprehensive river regulation project must be carried out. In this study, first, the factors influencing river health are discussed, and the principles and main restrictions involved in comprehensive regulations are studied. The scientific regulation mode is proposed, and new financing channels for water conservancy construction are also suggested. Second, a river reach adjacent to a city in the middle part of the Luanhe River in North China is used as a case study. The health status of the river is analyzed, and a comprehensive river regulation plan combined with urban development is put forward on this basis. The plan includes embankment construction, river regulations, multilevel rubber dam storage, ecological restoration, and artificial lake and riverside landscape construction. The influence of the engineering treatment on the river flood discharge capacity is examined, and the treatment effect is verified by a hydraulic scale model. After implementation of the comprehensive river regulations, the flood control safety of the city and river ecological environment are found to be significantly improved, with the hidden danger of dust storms eliminated. The treatment project incurs environmental, social, and economic benefits and preliminarily achieves the coordination and mutual promotion of river regulation and urban development

Concept and Practices Involved in Comprehensive River Control Based on the Synergy among Flood Control, Ecological Restoration, and Urban Development: A Case Study on a Valley Reach of Luanhe River in a Semiarid Region in North China

Many rivers in semiarid areas have ecological degradation and flood control problems that need to be addressed urgently. In order to maintain river health and to promote the sustainable development of cities near these rivers, a comprehensive river regulation project must be carried out. In this study, first, the factors influencing river health are discussed, and the principles and main restrictions involved in comprehensive regulations are studied. The scientific regulation mode is proposed, and new financing channels for water conservancy construction are also suggested. Second, a river reach adjacent to a city in the middle part of the Luanhe River in North China is used as a case study. The health status of the river is analyzed, and a comprehensive river regulation plan combined with urban development is put forward on this basis. The plan includes embankment construction, river regulations, multilevel rubber dam storage, ecological restoration, and artificial lake and riverside landscape construction. The influence of the engineering treatment on the river flood discharge capacity is examined, and the treatment effect is verified by a hydraulic scale model. After implementation of the comprehensive river regulations, the flood control safety of the city and river ecological environment are found to be significantly improved, with the hidden danger of dust storms eliminated. The treatment project incurs environmental, social, and economic benefits and preliminarily achieves the coordination and mutual promotion of river regulation and urban development

Mean-variance Trading Portfolio Selection for A Class of Energy Retailers

Due to the volatile price of various energy products, energy retailers in many countries are facing the risk of going bankrupt. This paper focuses on a class of energy retailers that trade energy products including the electricity option, the natural gas option and the white certificate. From the perspective of such energy retailers, this paper studies a portfolio selection strategy that can achieve the maximized asset value and mitigate the potential risk of purchasing energy products at high prices. Firstly, a class of linear ordinary differential equations (ODEs) and stochastic differential equations (SDEs) are used to model the dynamic time-varying price of electricity option, natural gas option and white certificate accurately. Secondly, based on the mean-variance model, the portfolio selection strategy problem of energy retailers trading these three products is formulated as a stochastic optimal control problem. Then, the linear-quadratic (LQ) control method is used to solve the problem analytically with mathematical theorem, and the obtain controller is indeed the desired optimal trading strategy. Finally, a series of examples demonstrating the correctness of the proposed portfolio selection strategy are provided

Mean-variance Trading Portfolio Selection for A Class of Energy Retailers

Due to the volatile price of various energy products, energy retailers in many countries are facing the risk of going bankrupt. This paper focuses on a class of energy retailers that trade energy products including the electricity option, the natural gas option and the white certificate. From the perspective of such energy retailers, this paper studies a portfolio selection strategy that can achieve the maximized asset value and mitigate the potential risk of purchasing energy products at high prices. Firstly, a class of linear ordinary differential equations (ODEs) and stochastic differential equations (SDEs) are used to model the dynamic time-varying price of electricity option, natural gas option and white certificate accurately. Secondly, based on the mean-variance model, the portfolio selection strategy problem of energy retailers trading these three products is formulated as a stochastic optimal control problem. Then, the linear-quadratic (LQ) control method is used to solve the problem analytically with mathematical theorem, and the obtain controller is indeed the desired optimal trading strategy. Finally, a series of examples demonstrating the correctness of the proposed portfolio selection strategy are provided