Papers by Author: Jin Lan Xu

Abstract: The Management Information System (MIS) on pipe bursts was developed by Visual Basic 6.0 to handle the accident data in water distribution networks. The thought of modular design is adopted in system design and the whole system is divided into four modules, including user login, database connection, database operation and data enquiry & analysis. The MIS has the functions of data input, output, storage, enquiry, statistics and analysis, which are implemented by component technology, ADO and SQL. Based on the functions it can achieve day-to-day management of network accidents and supply guidance of treatment measures. So the MIS on pipe bursts is a useful tool in network management.

Abstract: Based on the improved weighted-least-square model and fuzzy similarity ratio method, a methodology is proposed to detect pipe bursts in real-time. When SCADA data is obtained DFP algorithm is used to get the real network state. Then the real values of burst characteristics are computed. And the hypothetical values assuming each pipe as the accident pipe are calculated for comparison. The fuzzy similarity ratio method is used to judge whether there is a pipe burst. If there is, the hypothetical value that is most similar to the real value is the accidental state and the corresponding assumed break is the burst location. According to the methodology a software system is developed with Delphi 7 for verification. The running results of a designed network show that the methodology is reliable and its detection accuracy is over 45%.

Abstract: Abstract: Active barrier system (ABS) capping zeolite with large surface area and strong adsorption ability is an effective way to control eutrophication of lake since it can remove ammonia in the lake released by sediment. Influence of the initial nitrogen concentration on eliminating nitrogen load of europhia sediment capping with active barrier system (ABS) were studied through an investigation of the repairment results of serious pollution period (total nitrogen concentration up to 25.33 mg/L), moderate pollution period (14.39 mg/L) and the slight pollution period (3.47 mg/L) of the ancient Canal of Yangzhou. The results showed that: (1) zeolite F1 inhibition effect is stronger than zeolite F2. More TN were removed as the initial TN concentration increased and longer rapid inhibit period were presented with the increased initial TN concentration. (2) The ammonia nitrogen in sediment could be rapidly released into the overlying water, and with lower initial TN concentration in source water, more ammonia would be released from the sediment. Long time treatment was necessary to inhibit the release of ammonia completely if the water showed a high initial TN concentration. (3) After covering zeolite, the total nitrogen in the overlying water were removed mainly through nitrification and denitrification. At the initial TN concentration of 3.47 mg/L, 14.39 mg/L, 25.88 mg/L, 61%, 45% and 52% of TN were removed by the conversion of ammonia to nitrogen gas, however, others left in water as nitrate nitrogen and nitrite residues, and 90% was nitrate nitrogen.