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This paper presents a new method for describing the complexity of geographic line elements. Firstly, the Fourier series is used to transform the geographic line elements from the spatial domain to the frequency domain for analysis. Fourier expansions are performed on different geographic line elements to obtain different Fourier descriptors, then we use the method of setting the area threshold to control the deviation of the geographic elements before and after the Fourier expansion to a certain extent, so that the curve reduced by the Fourier descriptor can replace the original geographic line elements. Secondly, based on Shannon’ s information entropy theory, the amount of information of the fitted curve after Fourier expansion is calculated. Then, by combining the frequency domain with the fractal theory, the data of the amount of information is further processed based on the Head‐tail data break and Koch’ s Two‐Eighth Law, and the concept of the distribution index p is proposed. Finally, the distribution index and the square root model are combined, and the approximate expression of the distribution index of the map at different scales is obtained by the least squares method. We select the contour data of a region to conduct experiments, and experiment results show that the distribution index has a good expression effect on the complexity of geographic line elements at different scales, and can be applied to multi‐scale expression of line elements. [ABSTRACT FROM AUTHOR]

Upstream areas are the major flood contributing areas in humid regions. Upstream hillslopes, valleys and ephemeral channels provide quick pathways for flows during flood events. These pathways generate flows seasonally and only after a rainfall event, i. e., the hydrological connectivity is ephemeral. Thus the dynamics of drainage networks such as expansion/contraction, and connection/disconnection, may offer important clues to understanding the patterns and processes of runoff generation. However, the mechanism of what controls the hydrological connectivity and how it connects the hillslope, valley and channels is yet to be understood. Extensive field studies in diverse catchments around the world continue to characterize and catalogue the enormous heterogeneity of hillslope structures and complexity of rainfall runoff processes in multiple watersheds, and at different scales. But, these field findings seem to be meaningless for the modeler, as they usually fail to incorporated the experimentalist's knowledge into their models. There is plenty of knowledge gap in the fundamentals with regard to how catchment are composed, organized and connected through hillslopes, valleys and channels, and how catchment storage affects rainfall-runoff responses. In this study, through comparisons of hillslope experiments, we find that process based connectivity is deeply affected by hillslope soil depth, bedrock terrain and drainage network structures. This review also showed that present research works are focusing on micro-scale mechanism (e. g., soil pores and flow), and there is a gap between the hydrological connectivity experiments and the modelers. We suggest that experimentalists should find a macroscale pathway hidden in the critical zone that is the pivot of the runoff generation and shapes the flow hydrodynamics in the entire catchment. That is to say hydrological connectivity of hillslopes, valleys and ephemeral channels should focus on the cumulative effects of hillslope processes instead of individual soil pore processes. Finally, there should be a balance between conceptualizing of complex hillslope structures and moderate depiction of runoff generation. [ABSTRACT FROM AUTHOR]

Following the Millennium Declaration in 2000, the United Nations introduced eight Millennium Development Goals (MDGs) to: 1) eradicate poverty, 2) achieve universal primary education, 3) promote gender equality, 4) reduce child mortality, 5) improve maternal health, 6) combat HIV/AIDS, malaria and other diseases, 7) ensure environmental sustainability, and 8) establish global partnerships for development. MDGs as a whole have profound implications for public health since each goal is a proven health determinant. From policy to research, these goals shape the landscape of global health. As the 2015 deadline approaches, the international community shows intensified interest in assessing progress and setting a new set of goals in the framework of sustainable development. This article traces the socio-political context of the emergence of MDGs, reviews current progress and emerging issues, and identifies Taiwan's gaps in knowledge and action. It concludes by urging Taiwan to pay closer attention to global development issues and to participate in the post-2015 forum. [ABSTRACT FROM AUTHOR]