Advanced Materials Research Vols. 457-458

Abstract: This paper focuses on the thermo-mechanical behaviors of a shape memory alloy (SMA) plate with a crack of mode I. A phase transformation equation is supposed to express the phase transformation behaviors of SMA under complex stress state. The stress field near the crack tip is described based on linear elastic mechanics. The martensitic phase transformation zones near the crack tip at various temperatures are numerically determined.

Abstract: Agricultural technician is the direct impetus of agricultural economy. In order to establish an evaluation and prediction model for distribution of agriculture technicians in Guangdong Province, author discuss related theory such as Moran I model and GIS technique. An applicable computing routine was presented in this paper. Based on data from yearbook of agriculture in Guangdong province, we provided some result and conclusions of talent distribution in sample regions. The result reflects the influences of agricultural technicians’ factor to the agricultural economics which may provides decision support for agricultural technicians’ policy.

Abstract: The Decision Tree technology, which is the main technology of the Data Mining classification and forecast, is the classifying rule that infers the Decision Tree manifestation through group of out-of-orders, the non-rule examples. Based on the research background of The Decision Tree’s concept, the C4.5 Algorithm and the construction of The Decision Tree, the using of C4.5 Decision Tree Algorithm was applied to result analysis of students’ score for the purpose of improving the teaching quality.

Abstract: Aiming at the problem that contact advance lags seriously and automatic advance with shearer is not in time in ASQ of hydraulic support on fully mechanized coal mining face, this paper proposed a solution of adaptive advance system based on Neural Network PID. This advance method can effectively reduce invalid waiting time in advance and the probability that friction between top beam and roof increases, and thus to improve advancing velocity and achieve continuity of coal mining automation. This paper finally used SIMULINK to carry out simulation. Results show that Neural Network PID controller has better performance than conventional PID controller.

Abstract: As the complexity of marine environment and the existence of uncertain factors along with Unmanned Underwater Vehicle (UUV) dynamics itself bringing many nonlinear problems, it is difficult to control the navigation in accordance with a predetermined trajectory. Based on the UUV dynamics analysis and system modeling, this paper decoupled its control system into three sub-control systems, designed robust autopilot using H∞ mixed sensitivity control algorithm to generate the low-order controller to achieve independent control of three degrees of freedom. Eventually, the underwater navigation simulation results show that the proposed method can provide better control performance and the method is feasible and high efficiency in actual applications.

Abstract: A signature scheme is strongly unforgeable if the adversary cannot produce a new signature even on a queried message. Some methods have been proposed to enhance some regular signatures. However, if applied to ring signatures, such methods will break the anonymity, which is the soul of ring signatures. We introduce a modified method which can achieve both strong unforgeability and anonymity in the standard model. Applying this method to Shacham-Waters scheme, we get the first ring signature with strong unforgeability in the stand model.

Abstract: This paper, through studying of LED luminescence properties, presents a fast measurement method and device of LED sources spatial intensity distribution. This method is based on planar imaging, and it has significant merits of fast, easy operated, informative and real–time. The basic structure is LED luminous energy converges on image space through optical lens of a certain numerical aperture(NA). In image space, the energy on the defocused plane is collected with the imaging detector. Then, calculating energy distribution on object virtual plane from that on the image space defocused plane through imaging relationship. Thus, each point of the LED luminous intensity distribution on object virtual plane can be calculated. Tracepro simulation software is used to simulate energy distribution of the model, and the corresponding data analysis shows that planar imaging can accurately reflect the distribution of the LED light. This method has practical meanings for luminous flux measurement of some LEDs.

Abstract: The Internet of Things (IOT) is a self-styled term to describe a new network technology that make all of objects be able to communicate in the Internet via RFID and different sensor devices. It is the basis of intelligent management. In this paper, the concept of IOT was first explained from the side of technology and application etc. Then the model and architecture of IOT were analyzed in detail. Finally, this paper introduced the specific application of IOT in Urban agriculture, and gave the application frame model in agricultural production and agricultural product supply system.

Abstract: Mine geological factors involved in measuring systems are very complex, large amount of data and attribute more. In actual measurement, due to the precision of measuring instruments and measurement operations personnel and other reasons, the data is inevitably flawed, and then has the subsequent impact of the design, production and management. With intelligent technology and development of computer science, mine has an increasingly high demand of geologic measure data and there are more and more methods to deal with the data. In this paper, rough set theory is applied by analyzing the characteristics of geological measure data and the structure of the database, the corresponding model is established, the uncertainty is found from the database of knowledge and abnormal data, and geological measure dataand the noise in the process of knowledge discovery interference is eliminated. As rough set method is easy to execute in parallel, without any prior knowledge of data and automatically select the appropriate set of attributes, can greatly improve the efficiency of knowledge discovery, get rid of excess property, reduce error rates, then has more advantages in processing the mass of the geological measure data and mining a more realistic data than fuzzy sets and neural network method. In addition, it is easier to be proven and tested in the resulting decision rules and reasoning processes than the latter neural network method are, and the results obtained is more easily evaluated and interpreted. Thus, using rough sets to mine the geologic measure data and find the knowledge hidden in the data, and then make the forecast analysis and decision-support for mine production and management, which is more practical.

Abstract: In this paper, we investigate the solvability of matrix equations with -involutary symmetric matrix , the general solution of which is obtained when it is solvable. Meantime, the associated optimal approximation problem for some given matrix is also considered under some particular hypothesis.