Security Evaluation of Urban Water Resource: The Case of Hangzhou, Zhejiang Province

Abstract

Based on expert judgment method, determine index weight with AHP method. From 5 aspects of water resource “engineering security, economic security, living security, environmental security and sustainable development security”, construct a security evaluation index framework of urban water resource, including 16 evaluation indexes. According to system security, security of urban water resource is divided into 5 levels: hazardous, unsafe, safe, good and completely adaptive, and corresponding warning light is red, orange, yellow, blue and green. Empirical results show that factors restricting security of Hangzhou water resource are mainly water resource engineering security and sustainable development security.

Experimental Study on Particle Removal of a Wet Electrostatic Precipitator with Atomization of Charged Water Drops

“…Second, the corona current is mainly produced by electrons and ions because their migration velocity is far greater than that of charged particles . As the dust concentration increases, more electrons and ions will collide with particles, leading to their decrease and an increase in the number of charged particles, resulting in a decrease in the corona current under a constant applied voltage and causing insufficient charges of particles and reduction in removal efficiency . An increase of the dust concentration in the low range would mainly be affected by collision and agglomeration, thus bringing about an increase in grade removal efficiency as shown in Figure a.…”

Research on Technology of Process-Oriented Virtual Assembly Modeling for Product Information

“…This method emphasizes on expressing the geometry appearance information and does not take into account the non-geometry information such as constraint relation, engineering design and so on. Wan H. G from Zhejiang University [5] and Ma from City University of Hong Kong [6,7] adopt B-rep and CSG combination method to describe the geometry topology information, support 3D operation of virtual assembly and can meet the requirements on the model information completeness. However, the model information is expressed complicatedly, information updating and efficiency of management are low, and can not meet the real-time requirements.…”