Movable weirs have been developed to address the weaknesses of conventional fixed weirs. However, the structures for riverbed protection downstream of movable weirs are designed using the criteria of fixed weirs in most cases, and these applications cause problems, such as scour and deformation of structures, due to misunderstanding the difference between different types of structures. In this study, a hydraulic experiment was conducted to examine weir type-specific hydraulic phenomena, compare hydraulic jumps and downstream flow characteristics according to different weir types, and analyze hydraulic characteristics, such as changes in water levels, velocities and energy. Additionally, to control the flow generated by a sluice gate, energy dissipators were examined herein for their effectiveness in relation to different installation locations and heights. As a result, it was found that although sluice gates generated hydraulic jumps similar to those of fixed weirs, their downstream supercritical flow increased to eventually elongate the overall hydraulic jumps. In energy dissipator installation, installation heights were found to be sensitive to energy dissipation. The most effective energy dissipator height was 10% of the downstream free surface water depth in this experiment. Based on these findings, it seems desirable to use energy dissipators to reduce energy, as such dissipators were found to be effective in reducing hydraulic jumps and protecting the riverbed under sluice gates.

Many problems that are encountered in regards to water balance and resources management are related to challenges of economic development under limited resources and tough competition among various water uses. The development of major infrastructure like airports in remote areas that have limited water resources is becoming a common problem. In order to overcome these difficulties, water management has to articulate and combine several resources in order to respond to various demands while preserving the ecological quality of the environment. The paper discusses the interest in implementing the Smart Water Grid concept on Yeongjongdo Island, which is the location of Korea’s main airport. This new concept is based on the connection of various water resources and their optimized management with new information technology solutions. The proposed system integrates water generated through rainfall, external water resources (i.e., metropolitan water distribution system), gray water and other types of alternative water resources. The paper analyses the feasibility of this approach and explores interest in the Smart Water Grid concept.

In this paper, spatial and temporal characteristics of precipitation time series were studied for Mongolia. Precipitation chronological data sets were encoded from the GPCC (Global Precipitation Climatology Center) grid containing 1° × 1° resolutions during the 1986–2007 periods. For this study, regionally 39 and globally 24083 gridded products were employed to analyze the precipitation anomalies. The Mann-Kendall and Cumulative Sum of non-parametric tests are used in order to identify trends and change points in the summer precipitation time series. Through the statistical point of view among the Hangai and Khentai mountainous regions were found the major variation. Associated eigenvalues of the EOF (Empirical Orthogonal Function) and PCA (Principal Component Analysis) were applied to determine the amount of total explained variance and significant shifts into the temporal trends. First four EOF are accounted with a total 80.1% explained variance for annual precipitation while the first EOF was 48.7%, second EOF was 18.3%, third EOF was 9% and fourth EOF was 4.1% respectively. Nevertheless, individual summer season’s gridded precipitation time series were fitted and predicted through the adequate ARIMA (Autoregressive Integrated Moving Average) model which was presented in this paper.

This paper attempts to characterize regional drought using 0.5 degree reanalyzed GPCC (Global Precipitation Climatology Center) gauge-based gridded monthly precipitation data sets in Korea. Drought is a function of precipitation and long-term observed precipitation was performed to enhance this characterization. There are limited long-term records from each station, therefore, a global gridded data set has been employed. Before using this data, 10 corresponding grids with KMA (Korea Meteorology Administration) stations were validated through cross-correlations (0.93–0.99). The impacts of drought are dependent on its duration, severity and spatial extent. Drought occurs when a below average water availability persists and becomes regionally extensive. In this study, 66 GPCC gridded precipitations were employed to estimate the effective drought index along with the available water resource index. The results of the 10 KMA corresponding stations were as accurate as those of the global data. Consequently, gridded data are suitable for a monthly drought severity investigation. In addition, spatial distribution of drought and available water resources were exposed by kriging interpolation technique over Korea. Through this study, drought risk city Taebaek in Kangwon province was classified by its 2009 intensity of monthly precipitations, droughts and available water resources.