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In order to automatically generate the railway Alignment, an alignment optimization method based on minimum cost is proposed. Firstly, an optimization model based on the coupling constraints of line-structure-environment is established, in which the comprehensive cost of engineering, operations, and the environment is considered as the objective function. Then based on the regular grids, the Geographic Information Data can be obtained and the comprehensive cost of the connection between two grids can be calculated. At last, the optimal connection between the grids is analyzed under the angle constraint and elevation constraint, thus the optimal alignment can be generated by the connection of grids.

Pineapple leaf fiber is a nature hemp leaf fiber extracted from pineapple leaves. Its structural characteristics was investigated by means of scanning electron microscope (SEM), X-ray diffraction (XRD), Differential scanning calorimetry (DSC) and thermogravimetric analysis (TG). The results showed that the percent crystallinity and preferred orientation of crystallites in pineapple fibers were 60.82% and 98.5%, respectively. The average fracture strength of the pineapple leaf fiber is high and the linear density is low, so there is a high fiber spinnability and yarn quality. The present study is expected to provide essential information for the preparation and processing of pineapple leaf fibers.

As an important energy production and consumption area, the energy saving and emission reduction performance of thermal power enterprises relates to energy conservation and sustainable development of China’s economy. According to the energy saving policies of power industry, a comprehensive evaluation index system of energy saving and emission reduction performance was built, which contains of energy resource consumption, resource utilization, pollutants emissions and build business efficiency four aspects. The index weights were performed by AHP-entropy weight method considering the expertise and objective information. Meanwhile, an improved Matter-element Extension model was built to evaluate the energy saving and emission reduction performance of thermal power enterprise, in which the domain and standards of maximum degree in traditional model was improved. And an improved correlation function was proposed to instead of traditional correlation function, which is based on both maximum membership degree principle and closeness principles. Finally, the numerical results validate the effectiveness and practicality of the improved model.

The higher order maximal orthogonal vector basis functions are used to get targets sampling information in interpolation/extrapolation of electromagnetic responses in time and frequency domain. With the method, the computational complexity of sampling would decrease sharply without loss of accuracy. As a result, the proposed method solved the problem of high computational complexity and great resource consuming of traditional sampling method. Some numerical results are given to verify the high efficiency and accuracy of this method.

The emergency escape hatches of refuge cabin are usually installed in both sides of the life supporting compartment, which might cause the toxic gases or water enter into life supporting compartment when the gas explosion and water inrush accident occur. A new type of refuge cabin structure that can effectively resist the toxic gases and water entering the life supporting compartment is developed in this paper. Numerical simulation of antiknock impact performance of the new refuge cabin was calculated and analyzed by using the finite element software of LS-DYNA.The stress and strain distributions and maximum antiknock performance were obtained. Refuge chamber cabin has been optimized to reduce cost. The antiknock impact performance of optimized mine refuge chamber cabin can reach 1.4MPa which is greater than the 0.6MPa of standard value and the cost can be reduced approximate 19% than the original model.

With the advent of Internet of things, more and more applications require location-based services. This paper firstly introduces classification of positioning technology, then some of the commonly used positioning technology is discussed, and finally the advantages and disadvantages of them are analyzed and compared.

Propose a detective method of road roughness based on MEMS inertial sensor. This detective method utilizes a unit integrated MEMS inertial sensors and GPS module to perceive the information of road and then achieve the detection of road roughness. Firstly, establish the Gaussian mixture model (GMM) to process the collecting information of acceleration and gyroscope, extract the abnormal events of road. Secondly, use a Concept-Based data clustering model (CBDCM) to achieve the feature description and extraction of various abnormal events. Finally, utilize the position information supplied by GPS to locate the detected road potholes, achieve the detection and supervision of road roughness. Combined with the designed system to conduct test, the experimental result indicates the Fall-out ratio and Omission ratio of pothole events about this detective method is 7.4% and 5.3%, it indicates that the detective method has a high practical value.

Multi-point boundary value problem is studied in this paper. With the condition that nonlinear term is superlinear or sublinear, it is proved that there exists at least one positive solution to multi-point Sturm-Liouville boundary value problem by using the fixed-point theorem concerning cone expansion and compression of norm type.

In 1994, C.Thomassen proved that every planar graph is (namely ). In 1993, M.Voigt shown that there are planar graphs which are not . But no one know whether every planar graph is . In this paper, we give a important property on planar graph that “Every planar graph is ” and “Every planar graph is free ” are equivalent.

Information security problem has become one of the hottest issues in RFID system. More and more researchers begin to study how to provide security protection in the RFID system. In the paper, we mainly research lightweight authentication protocols in RFID system. Firstly, we analyze some protocols. Secondly, we introduce a serverless authentication protocol for RFID system and analyze its security. We find it does not provide forward security. Thirdly, we propose a revised serverless authentication protocol with forward security. It provides two-way authentication and privacy protection, resists tracking and cloning attack as well as the original protocol. Moreover, it provides forward security protection and resists desynchronization attack. For the efficiency, its computational complexity is at the same level with the protocol proposed by Tan et al.

RFID has become an important infrastructure technology. However, it does not solve information security problem. An adversary can eavesdrop on the messages exchanged between tag and backend database and track tag’s holder. Many scholars have proposed some lightweight protocols in order to protect user’s privacy and avoid various attacks. In this paper, we analyze some authentication protocols. Especially, we analyze a forward secure RFID privacy protection scheme proposed by Ohkubo et al. Afterwards, we propose an improved protection scheme with two-way authentication. It is lightweight and suitable for low-cost RFID system. Moreover, it not only provides indistinguishability and forward security but also provides two-way authentication.

This thesis designed a high degree of intelligence charger to solve the Lead-acid batteries’ problems. The design of charger including two parts, hardware design and software design. PIC16F877 is the core control component in hardware part, on this basis, design the corresponding peripheral circuits .And the designing of hardware circuit and driver software of the whole system is explained in detail.