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Compared with the Intrusion Detection (ID) based on pattern matching, the model-checking-based methods can find the complex attacks. But their rates of missing report are still high. To solve this problem, we firstly use the Interval Temporal Logic with Past Construct (ITLPC) formulae to describe some signatures for network attacks. And then, we can use some automata to establish models of audit logs. On the basis of it, automata, i.e., attack models, and ITLPC formulae, i.e., signatures, constitute the two inputs of the ITLPC model checking algorithm. Therefore, a new model-checking-based ID algorithm is obtained by calling the ITLPC algorithm. Compared with the existing methods, the new method is more powerful, as shown in the experimental simulations.

Compared with the intrusion detection based on pattern matching, the method which is based on model checking can detect the complex attacks. But all of the existing algorithms are only used to detect some specific types of attacks. To solve this problem, we firstly use the Linear Temporal Logic with Past Construct (LTLPC) formulae to set up formal sub-models for the five kinds of attackers, the four kinds of attack processes and the eight kinds of attack effects. According to their universal relationship and the semantic relation of variety of LTLPC operators, we obtain the above sub-models together, thus, the universal models described by LTLPC formulae for universal attacks are formed. On this base, we implement an intrusion detection method based on LTLPC for detecting all types of attacks. Compared with the existing methods, the detecting ability of the new method is more comprehensive.

In this paper, we present an efficient approach based on Smoothed Particle Hydrodynamics (SPH) to simulate nearly incompressible fluids. The proposed method is an extension of the traditional SPH method designed for compressible fluids. We first introduce a new scheme for pressure evaluation to satisfy the incompressibility constraints. Then novel calculation methods for pressure force and viscosity force are discussed. Finally, the results demonstrate that our method is more capable of realistically simulating fluids with near-incompressibility than previous method.

In this paper, we find that factors which affect energy consumption are steel ratio coefficient and process energy consumption by analyzing energy consumption of every process in integrated steel works. On this basis we point out the main reason for the high energy consumption of iron and steel industry in China is that integrated steel works examine the production process without system energy saving ideas. Therefore we propose the countermeasures of energy saving in iron and steel industry in China in aspects of energy management and control center, iron-making system, steel-making system, steel rolling system, as well as secondary energy recovery, which is aimed at providing a way for energy saving and emissions reduction of iron and steel industry in China.