Cooperation between CAS and Local Authorities

Safety Analysis of Power Grid

T. John Koo, Professor of the Shenzhen Institutes of Advanced Technology, CAS, and his co-authors of the Kyoto University and Kansai Electric Power Co. Inc. published their joint paper entitled “A Hybrid System Approach to the Analysis and Design of Power Grid Dynamic Performance” in the Special Issue on Cyber-Physical Systems of the Proceedings of the IEEE, Vol. 100, No. 1, January 2012, which is the first issue for celebrating its centennial year of publication. The joint paper includes the collaborative research works developed during 2005-2009. Power grid is a large-scale Cyber-Physical System for transmission of electrical energy. The joint dynamics of physical processes and cyber elements in power grids are typical of a mixture of continuous and discrete behaviors. Hybrid systems are useful models for capturing the complex behaviors. Measures for stability of power grids can be interpreted as safety specifications in hybrid system models. Reachability algorithms are proposed for the analysis of reachable sets, which are the sets of all states that can be reached by the models in some time. Reachable set provides the coverage of the state space that can hardly be produced by using only a finite number of simulation traces. For the transient stability of the SMIB (Single Machine-Infinite Bus), an hybrid system model is used for representing the dynamical effect of the re-closing operation of SMIB and the reachability analysis of the hybrid system model specifies a set of initial states in which the synchronous machine does not show any loss of transient stability with respect to the infinite bus.

Atlantic Salmon Produced from Recirculating Aquaculture Systems

This project, completed by the Institute of Oceanology, CAS and the Shandong Oriental Ocean Sci-Tech Co.,Ltd, has become the largest recirculating aquaculture systems of commercial fish production. This research has combined international advanced experience and local underground water maintained at 12-15℃, completed and optimized the existing recirculating aquaculture process based on integrated and independent innovation. In the new process, mechanic filtration, solid-liquid separation, foam separation, CO2 degassing, UV/O3 disinfection and bio-filter aiming at NH3-N、NO2-N removal are set up, meanwhile, facilities such as automatic control, remote alarm, self-aeration, computer controlled feeding and water quality online monitor has reinforced the systematic stability and reliability, and create suitable water quality and environment appropriate for Atlantic salmon(Salmo salar) growth.

Critical Tech on Electro-synthesis of Sodium Dichromate Sees Breakthrough

On Jan. 2, 2012, a project of “Research on the Critical Technology of Electro-synthesis of Sodium dichromate” undertaken jointly by the CAS Institute of Salt Lake and the Qinghai Chromate High-tech Co. successfully passed its final acceptance check. The technology innovated is used as demonstration for the Qinghai chromium project, which was promoted as one of the four processes for national chromium projects. Chromium products, as important chemical materials are widely used in different areas, but such products are easily oxidized, and thus can destroy and corrode organisms. The traditional chromic salt process produced great waste residues, liquid wastes and waste gas. The chromic salt industry used to be a serious polluted trade in China, and solution for this has been a long time concern. The new process, taking sodium chromate as raw material, adopted electrolysis in two phases, has finally solved the key technological problem occurred in the electro synthesis of sodium dichromate. The new process boasts for its shorter process, higher purity, less pollutants, and higher efficiency. The first pilot plant using electro-synthesis for production of chromium products has been completed with capacity of 500 tons.