Advanced Materials Research Vols. 143-144

Abstract: This paper proposes a novel entropy-based metric for evaluating silent cascade which is a prevalent trajectory privacy preserving method in LBSs (location-based services). Within this measure, the trajectory privacy is quantified as the probability of the relevance between the user’s pseudonym before and after each mix-zone. After a period of time, the tracked user may take many potential trajectories from the perspective of the adversary. The user’s trajectory privacy level is calculated using information entropy. The most distinguishable aspect of the measure is to take into account the adversarial background knowledge. We develop methods to describe and quantify the adversarial background knowledge. Simulation results reflect the impact of background knowledge on the privacy level in the metric, and show that this metric is effective and valuable to measure the user’s trajectory privacy level correctly even the adversary has variable background knowledge.

Abstract: The integration of DL and distance education is a significant topic of theoretical and practical research. This paper mainly discusses the principles of knowledge service of DL and four knowledge service models for distance education under the principles, namely, specialized service model based on subject knowledge base, content-based reference service model, personalized custom-made service model, and teamwork service model. The key point of realizing these models is to take distance education users as the center, set up subject information service platform, personalized information push platform, subject librarian knowledge service platform and platform for learning resource sharing and system interoperability, and properly integrate these platforms.

Abstract: Digital library construction needs knowledge organization technologies support. In this paper, we probe into the technologies from three dimensions. The grammatical technologies include metadata, XML, RDF and etc. This type mainly focuses on how to describe data efficiently in terms of the outer characteristics of data. The semantic technologies include Topic map, Ontology, semantic web and etc. They mainly describe the content of data, finding the relations between each other.The pragmatic technologies include grid, database and etc. They want to control the information, and make it used efficiently.

Abstract: This paper proposes a simple method dealing with chattering phenomenon of sliding mode control. Instead of using a linear function to smooth the discontinuous control when the system is within the boundary layer, the controller adopts a smooth nonlinear function which we call a nonlinear saturation function (nsat function). Compared with the conventional linear saturation function (sat function), the nsat function can be constructed arbitrarily and shall satisfy eight conditions. Seven of the conditions are used to get a better effect in reducing chattering and one is used to keep a fast response performance by adjusting one constant parameter . As the nsat function can be specified by , it can be calculated in advance; this makes the nsat function of high computation efficiency and makes it acceptable in real time control systems. One candidate nsat function is constructed by adopting a hyperbolic tangent function and it is adopted in the simulations running on a second order system. Simulation results show that the nsat function also results in a smaller tracking error.

Abstract: Retracted paper: Using the theory of explosion mechanics and gas detonation dynamics and the conservation law of mass, momentum and energy, the physical and mathematical models of damage effect are set up in excavation roadway during gas explosion. In view of gas concentration, accumulation position, volumes and states of spaces, the shock wave damage on structures in the roadway during gas explosion. The damage effects are characterized of heat and mechanic damage. Meanwhile, the high temperature and pressure are formed in different degree. With the action of overpressure and impulse, the damage degree is different with different geometric structures in ventilation system. By means of basic condition, influential factors, procedure features and simulation, some unnecessary structures or barriers should be cleared in order to keep smooth the ventilation system.

Abstract: Retracted paper: The networking approach to the World Wide Web is defined not only by the exploration of architecture, but also by the confirmed need for interrupts. Given the current status of authenticated archetypes, steganographers dubiously desire the analysis of scatter/gather I/O. the focus in this position paper is not on whether Moore's Law can be made concurrent, distributed, and pervasive, but rather on proposing an analysis of 32 bit architectures (Grange). It is concluded that, using probabilistic and interactive information and based on relational modality, the machine system and kernels are verified, which is widely used in the future.

Abstract: The volatilization process of oil with uniform size media as underlying material was studied. The weight loss of oil was determined by subtracting the columns’ pre and post weight measured on an electronic balance. The results show that the gasoline in porous media volatilizes at a logarithmic rate with respect to time, and the diesel oil in porous media volatilizes at a rate which can be best modelled as a square root of time. The volatilization coefficient of gasoline increases with the increment of particle size, and it of diesel oil decreases with increment of particle size. Binomial equation and power equation can describe the relationships of gasoline and diesel oil volatilization coefficients with mean grain size respectively.

Abstract: SMS is the widely used service of mobile telephony technology. SMSCs developed by different companies use their own communication protocol and most of these protocols are proprietary. It can be solved using the SMS gateway, the SMS gateway acts as a relay between the two SMSCs. It is able to translate one SMSC protocol to another, and can be used by two different wireless carriers to interconnect their SMSCs. We describe the Structure Of SMS System, the Relation Class of SMS System and the process of designing the SMS Gateway

Abstract: Airway network planning has important value to ensure safe and decrease the flight cost. Consideration to economic benefits of the airlines and social benefits of the civil management department, airway network bilevel programming model and the constraints in the demand, traffic capacity, controller’s workload and traffic flow balance is proposed on the combination of road network planning with industrial characteristics of airway network planning. Based on genetic algorithm, the steps of airway network planning model is given. Finally, the model is verified by the sample's computation and analysis.

Abstract: The itaconic acid polymers of low molecular weights were prepared from itaconic acid wastes. The waste solution was distillated under vacuum of 2.00 kPa and temperature of 40-90 °C to reclaim the used solvents. The remains were neutralized by NaOH, initiated by 5 wt. % potassium persulfate under nitrogen protection and polymerized in water for 12 h at temperature of 100-102 °C in consequence to prepare the itaconic acid polymers. The scale inhibition efficiency could reach 99.51% with a polymer amount of 15 mg/L in the water sample with Ca2+ and HCO3- concentrations of 240 mg/L and 732 mg/L. The corrosion inhibition efficiency of polymers could reach 97.89% in the industrial circulating water with Ca2+, alkalinity and total hardness of 480 mg/L, 341 mg/L and 598 mg/L (all calculated in CaCO3 content). The biodegradation rate of polymers could attain 82.11% in the microorganisms environment at 35 days of operation.