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Summary: Resource volatility is a major challenge on desktop grid platforms with characteristics that primarily depend on human computer usage behavior. This study proposes a trust model based on Dempster–Shafer theory that predicts the relative reliability of nodes using information on daily computer usage behavior based on the historical information from a desktop grid platform for a desktop grid. In the proposed trust model, called TM‐DG, a degree of trustworthiness is introduced for the nodes to quantify their reliability. Dempster's rule of combination is also applied to exploit two bodies of independent evidence: 1) current node availability as actively probed by a special test node and 2) proportion of allocated tasks successfully completed. The simulations performed on a lightweight desktop grid platform illustrate how TM‐DG can fully utilize the most reliable nodes for a given computation, leading to a reduction in the communication overhead and an improvement in the computing power of the platform. [ABSTRACT FROM AUTHOR]

Danjiangkou Reservoir is the source reservoir of the Middle Route of the South-to-North Water Diversion Project (MRP). Any sudden water pollution accident in the reservoir would threaten the water supply of the MRP. We established a 3-D hydrodynamic and water quality model for the Danjiangkou Reservoir, and proposed scientific suggestions on the prevention and emergency management for sudden water pollution accidents based on simulated results. Simulations were performed on 20 hypothetical pollutant discharge locations and 3 assumed amounts, in order to model the effect of pollutant spreading under different reservoir operation types. The results showed that both the location and mass of pollution affected water quality; however, different reservoir operation types had little effect. Five joint regulation scenarios, which altered the hydrodynamic processes of water conveyance for the Danjiangkou and Taocha dams, were considered for controlling pollution dispersion. The results showed that the spread of a pollutant could be effectively controlled through the joint regulation of the two dams and that the collaborative operation of the Danjiangkou and Taocha dams is critical for ensuring the security of water quality along the MRP. [ABSTRACT FROM AUTHOR]

This study identifies the driving forces behind maximizing Tianjin’s industrial water use efficiency in China. For this purpose, a decomposition method is developed to quantify the degree of the impact of each factor. The results show that industrial expansion was responsible for an increase in annual water use of 78 million m³, while technical advances and water efficiency measures contributed annual water savings of about 76 million m³. Further, the results highlight that Tianjin has not considered the rise in water efficiency to be the primary goal of restructuring local industries over the past decade. [ABSTRACT FROM PUBLISHER]

At present, the urbanization and energy consumption complex system enters the stage of ultimate development. So it is not certain about synergistic development. From the perspective of causal feedback mechanism system and based on the mechanism of various elements of urbanization and energy consumption, this paper explores the path of synergistic development of urbanization and energy consumption, simulates the baseline scenario from 2005 to 2020 through establishment of the SD model of urbanization and energy consumption complex system, predicts the future behavior of the state variable when the control variable changes in the system through simulation, seeks for interaction and interrelationships between various elements in the process of evolution and development, and finally puts forward three paths to optimize the synergistic development of urbanization and energy consumption which are population transfer, industrial upgrading and technological improvement, which provides some references and foundation for making decisions of synergistic development of new urbanization and energy consumption. [ABSTRACT FROM AUTHOR]

The completion of Shuibuya, the last hydropower station to be constructed in the Qingjiang cascade, signifies China's successful development of the world's largest mixed cascade hydropower generation system. Joint operation of such cascaded hydropower stations is considered necessary to improve hydropower output in China. In this study, two modeling methods – routine and optimal operations – were adopted, based on existing rules of reservoir operation, to determine the effects of joint operation. To investigate the realistic and potential effects, the two models were computed using observed runoff data (1951–2009). The potential effects were identified by comparing the total hydropower generation two single cascades and their cogeneration. Under the routine operational mode, the incremental power generation of joint operation would be 5.73 × 10 8 kWh, an increase of 5‰ compared to isolated operation. However, even in isolation, if reservoir operation is optimized through the dynamic programming algorithm, the incremental power generation of the cascade would be 42.24 × 10 8 kWh, which is seven times that of joint operation with routine reservoir operation (5.73 × 10 8 kWh). The results showed that, under current reservoir operating rules, there is little room for improvement in hydropower generation, although joint operation could increase hydropower generation to a certain extent, especially in the reservoirs' refill and release stages. China must amend its existing operational mode for reservoirs to enhance the economic benefits of cascade hydropower stations. Furthermore, to meet increasing demands for both water and energy, carefully considered planning of constructing clusters of these stations is required. [ABSTRACT FROM AUTHOR]