Key Engineering Materials Vols. 474-476

Abstract: RFID technology plays an important role in our daily life nowadays. It widely used in the automatic identification system by embedding the tag into product. However, some security risks presented due to radio frequency signal channel between the tag and the reader which may lead privacy disclosure for the user. Various solutions are proposed to resole to security issues in RFID system, but there still presented some limitations. A security elliptic curve cryptography based authentication protocol is presented in this paper to preserve the privacy of the RFID system. The proposed protocol provides mutual authentication and a security communication channel between the tag and the reader. By the security analysis, our protocol can resist common passive and active attack; moreover, it also can provide forward security.

Abstract: This paper is to illustrate the Cellular Differential Evolution with the cellular structure originated from Cellular automata. Cellular neighbor local search has been designed; base vector or global best in mutation operator is substituted by neighborhood-best, which overcomes the weakness of single selection relating to global best, and balances the contradiction of local and global search, and improves the diversity of population. In addition, cellular structure ensures information exchange, inheritance and diffusion. Finally, a specific algorithm has been implemented: compared with similar variants of DE, the simulation results on 9 benchmark functions demonstrate that cellular differential evolutions are provided with obvious advantages in the solution-quality, stability and speed.

Abstract: Magnetic nano-particles are extensively studied in tumor therapy, target drug, gene screen, cell separation and magnetic resonance imaging study, due to theirs unique features such as its superparamagnetism, high saturation magnetization and high effective surface areas, etc. The aim of this work is to emphasize on the preparation and characterization of Fe3O4 magnetic nano-particles and its applications in hyperthermia . As the results, the Fe3O4 magnetic nanoparticle in this work has shown good qualities as well as in the literatures. It may be feasible to utilize in the field of hyperthermia.

Abstract: This paper presents a new model (SMF-Chord) which is expanded from Chord. SMF-Chord uses double-fingerprint, double-mapping and dynamic forwarding mechanism to support multi-attribute multi-keyword fuzzy-matching query, and also has a load balancing mechanism which includes three parts: similar-close transposition, forward balancing and hot-set cache. The experiment results show SMF-Chord has high recall rate with low storage redundancy, and it can effectively balance load when node mapping load, file storage load, or query load is unbalanced.

Abstract: Based on the characteristic of distress in Qijia mountain road tunnel, thickness, cavity distribution, crevice water were detected with geo-radar. Material of lining was nondestructive detected with sound locater. Limiting structure of the tunnel was detected with circumscription apparatus. Based on detected results cause of the distress was analyzed. Three treatment schemes were put forward by slurry injection from the back of lining structure, reinforcement lining, treating the water proof system. Stability of surrounding rock and the state of forces of the lining structure were analyzed before and after treatment. It is showed that the treatment scheme of the tunnel is feasible. Taken construction and cost estimate into account, optimal scheme is obtained.

Abstract: Step-size is one of the important parameters which influence the performance of blind equalization, a variable step-size method control by attenuation function according to instantaneous gradient and iterative times is proposed in this paper. Initially, set larger step-size to obtain faster convergence, with iterative times increasing, step-size would decrease control by attenuation function for instantaneous gradient reducing. Step-size changes according to this method consistent with the demand variable step-size adaptive algorithm that can obtain combination of convergence rate and convergence precision to improve the performance of blind equalization. Simulations show that this method performs better than conventional blind equalization with constant step-size.

Abstract: A directly rapid quantitative analysis method for chemical oxygen demand (COD) of wastewater was established by Fourier transform infrared (FTIR) spectroscopy and attenuated total reflection (ATR) technology. The combination selection of Savitzky-Golay (SG) smoothing modes combined with partial least squares (PLS) factor was applied to the model optimization here. The optimal smoothing parameters were 2^nd order derivative smoothing, 6^th degree polynomial and 51 smoothing points. The corresponding optimal PLS factor, root mean squared error of predication (RMSEP) and correlation coefficient of predication (R_P) were 11, 24.4 (mg/L) and 0.968 respectively, which was obviously superior to the direct PLS model without SG smoothing. This demonstrated that the combination selection of SG smoothing parameters and PLS factor can be effectively applied to the model optimization for FTIR/ATR analysis of COD in wastewater.

Abstract: There has been a modularization trend in manufacturing industry since 1990s. Modular network is a simpler and more effective way to form complex product system. The information processing in modular network includes information assimilation and information encapsulation. The competitive advantages of modular network lie in Network Externality, back-to-back competition, innovation and anti-risk abilities. The emergence of modular network leads to the change of industrial organization. Adjustments should be made to enterprises’ competition strategies.

Abstract: The multi-objective optimal design of a piezoelectric sandwich ultrasonic transducer is studied. The maximum vibration amplitude and the minimum electrical input power are considered as optimization objectives. Design variables involve continuous variables (dimensions of the transducer) and discrete variables (material types). Based on analytical models, the optimal design is formulated as a constrained multi-objective optimization problem. The optimization problem is then solved by using the elitist non-dominated sorting genetic algorithm (NSGA-II) and Pareto-optimal designs are obtained. The optimized results are analyzed and the preferred design is proposed. The optimization procedure presented in this contribution can be applied in multi-objective optimization problems of other piezoelectric transducers.

Abstract: Methane monitoring and alarm system is very important because it guarantees the coal mine production safety. After analyzing impact factors on methane monitoring, this paper established a mathematical model of gas detection system and introduced the key technologies for maintenance-free is dynamic adjusting of system state, auto-zero, auto calibrations of nonlinear and post-processing of the data. The hardware architecture of the mini intelligent methane sensor based WSN (Wireless Sensor Network) and the automatic and visualized calibration technologies of intelligent methane detecting system are described in detail. Finally, the experimental data is analyzed. The system improved the detection accuracy, prolonged calibration cycle of the methane measuring device and lessened the working strength on calibration.