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Space-related science and technologies affect our daily life dramatically. Many countries have already formulated national space regulations to regulate their space activities. China, as one space-faring country, has obtained impressive achievements in space science and technologies. In recent years, Chinese private space companies have sprung up quickly, which requires a stable and foreseeable legal framework to ensure development. However, compared to the other space powers, China is the only one that has not enacted any formal national space laws. Against the background of strengthening the rule of law in China, research on China´s domestic space legislation is valuable and significant. The purpose of this thesis is two-fold. First, to find the legal basis and necessity of national space legislation and to extract the basic content of the existing national space legislation, simultaneously, to identify the new developments in the content of other States´ legislative practices. Second, based on the study of national space legislation, to propose the essential content of China´s space legislation. ; Weltraumbezogene Wissenschaft und Technologien beeinflussen unseren Alltag dramatisch. Viele Länder haben bereits nationale Raumfahrtvorschriften formuliert, um ihre Weltraumaktivitäten zu regeln. China als ein Weltraumland hat beeindruckende Erfolge in der Weltraumwissenschaft und -technologie erzielt. In den letzten Jahren sind chinesische private Raumfahrtunternehmen schnell aufgestiegen, was einen stabilen und vorhersehbaren rechtlichen Rahmen erfordert, um die Entwicklung sicherzustellen. Verglichen mit den anderen Weltraummächten ist China jedoch das einzige, das keine formellen nationalen Raumfahrtgesetze erlassen hat. Vor dem Hintergrund der Stärkung der Rechtsstaatlichkeit in China ist die Erforschung der chinesischen Raumfahrtgesetzgebung in China von großem Wert. Der Zweck dieser Arbeit ist zweifach. Erstens, um die Rechtsgrundlage und Notwendigkeit der nationalen Weltraumgesetzgebung zu ermitteln und gleichzeitig den grundlegenden Inhalt der bestehenden nationalen Weltraumgesetzgebung zu extrahieren, um gleichzeitig die neuen Entwicklungen in Bezug auf die Gesetzgebungspraktiken anderer Staaten zu ermitteln. Zweitens, basierend auf der Studie der nationalen Weltraumgesetzgebung, um den wesentlichen Inhalt der chinesischen Weltraumgesetzgebung vorzuschlagen.

This monograph explores the design of controllers that suppress oscillations and instabilities in congested traffic flow using PDE backstepping methods. The first part of the text is concerned with basic backstepping control of freeway traffic using the Aw-Rascle-Zhang (ARZ) second-order PDE model. It begins by illustrating a basic control problem suppressing traffic with stop-and-go oscillations downstream of ramp metering before turning to the more challenging case for traffic upstream of ramp metering. The authors demonstrate how to design state observers for the purpose of stabilization using output-feedback control. Experimental traffic data are then used to calibrate the ARZ model and validate the boundary observer design. Because large uncertainties may arise in traffic models, adaptive control and reinforcement learning methods are also explored in detail. Part II then extends the conventional ARZ model utilized until this point in order to address more complex traffic conditions: multi-lane traffic, multi-class traffic, networks of freeway segments, and driver use of routing apps. The final chapters demonstrate the use of the Lighthill-Whitham-Richards (LWR) first-order PDE model to regulate congestion in traffic flows and to optimize flow through a bottleneck. In order to make the text self-contained, an introduction to the PDE backstepping method for systems of coupled first-order hyperbolic PDEs is included. Traffic Congestion Control by PDE Backstepping is ideal for control theorists working on control of systems modeled by PDEs and for traffic engineers and applied scientists working on unsteady traffic flows. It will also be a valuable resource for researchers interested in boundary control of coupled systems of first-order hyperbolic PDEs.

A river watershed is a complicated ecosystem, and its spatial structure and temporal dynamics are driven by various natural factors such as soil properties and topographic features, human activities, and their interactions. Thus, characterizing the river watershed ecosystem and monitoring its dynamics is very challenging. In this study, we explored the characteristics of the ecosystem and environment of Yalong River watershed in Ganzi Tibetan Autonomous Prefecture, Sichuan Province of China by analyzing and modeling the relationships among economic indices, heavy metal elements and landscape metrics. Landsat 8 data were used to generate a land cover classification map and to derive landscape pattern indices. Governmental finance statistics yearbook data were referred to provide economic indices. Moreover, a total of 9 water samples were collected from the upstream to the downstream to obtain the values of heavy metal concentrations in the water body. Then, both correlation and regression analyses were applied to analyze and model the relationships among these indices. The results of this study showed that 1) The ecological status and process of this river watershed could be explained by analyzing the relationships among the economic indices, heavy metal elements and landscape pattern indices selected based on correlation analysis; 2) Compared with the economic indices, the accumulated economic indices were more significantly correlated with most of the heavy metal elements and should be applied for the integrated assessment of the watershed ecological environment; 3) Landscape pattern indices SHDI and IJI had strong correlations with the important economic indices Population and Population Density and could be used for the integrated assessment of the watershed characteristics; 4) Compared with land cover area, land cover area ratios were more sensitive to the variation of the economic indices. The dominated land cover types Forest and Grassland had strong relationships with the economic indices; and 5) Cu and Zn had significant correlations with the landscape pattern indices. This study implied that analyzing and modeling the relationships among the economic indices, heavy metal elements and landscape pattern indices can provide a powerful tool for characterizing the ecosystem of the river watershed and useful guidelines for the watershed management and sustainable development.

Food security and cultivated land utilization can be seriously affected by heavy metal (HM) pollution of the soil. Therefore, identifying the pollution sources of farmland is the way to control soil pollution and enhance soil quality effectively. In this research, 95 surface soil samples, 34 vegetable samples, 27 irrigation water samples, and 20 fertilizer samples were collected from the Wuqing District of Tianjin City, China and was used to determine their HMs accumulation and potential ecological risks. Then, kriging interpolation and positive matrix factorization (PMF) were utilized to identify the sources of soil HMs. The results indicated that soil HMs in the study area were contaminated at a medium level, but that the pollution of Cd was more severe, and the Cd content in vegetables was slightly higher than the permissible threshold (0.02 mg·kg(−1)). Furthermore, a non-homogeneous distribution was observed, with higher concentrations of HM contaminants concentrated in the southwest of the study area, where many metal manufacturing industries are located. Our results suggest that the Cd originated from industrial activity; As and Pb from agricultural practices; Ni, Cu, Cr, and As mainly from natural sources; Zn and Cu from organic fertilizer; Pb and Cd mainly from traffic discharge; and Cr, Ni, and Pb from sewage irrigation. Obviously, the accumulation of soil HMs in the study area could be mainly attributed to industrial activities, implying the need for implementation of government strategies to reduce industrial point-source pollution.