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The new extrusion route of ECAP which is called route 135 was put forward in this paper. The grain refinement of the traditional extrusion route BCand the new route of ECAP process in 99.9995% (5N5) high purity aluminum was compared using a die with a channel-intersection angle 90°. It was found through experiment that, the grain was very coarse in the cast ingot of 5N5 high purity aluminum, and the average grain size is about 60mm. High purity aluminum processed by one pass ECAP was refined notably, and average grain size is about 1000 μm. After two ECAP passes, the average grain size is 200μm with route BC, while it is less than 50μm with route 135. The refinement of two passes of route 135 is equivalent to the refinement of eight passes of route BC. It indicates that the route 135 is more effective than route BC. TEM micrograph of 5N5 high purity Al with different ECAP pass under route BCand route 135 was studied.

The signal noise ratio (SNR) of telemetry signals is low in the environment of reentry telemetry, MSD(Multi-Symbol Detection) technology can effectively improve PCM/FM telemetry signal demodulation performance. In view of the problem that maximum likelihood value is misjudged leaded by the noise in the process of reentry and doppler causing serious distortion of signal phase. A performance compensation method of MSD based on sliding strategy is researched: A MSD operation with N-1 element overlap before each MSD operation, where the each symbol sliding strategy sliding the length of 1 symbol. The simulation and test results verify the effectiveness of the improved algorithm.

In order to improve the performance of PCM/FM signal demodulation system, this paper studies a kind of Symbol Detection more (Multi-Symbol Detection, MSD) technology. First for PCM/FM in hardware demodulation, a series of problems in the introduction of MSD software demodulation method; Then the MSD demodulation under low SNR synchronous implementation; The algorithm simulation, the results show that the bit error rate of 10-4, detection performance than traditional non-coherent frequency discrimination algorithm can improve the nearly 3 dB, the performance is very ideal.

The silicon steel was rolled to 95% reduction at 20°C, 400°C and 600°C, and subsequently annealed at different temperatures to obtain complete recrystallization microstructure without appreciable grain growth. The effects of rolling temperature on through-thickness deformation and recrystallization textures were investigated by ODF analysis. The deformation textures are all composed of α- and γ-fiber, whereas α-fiber and {111}﹤110﹥ decrease and {111}﹤112﹥ increases with the increasing rolling temperature. Through-thickness recrystallization texture varied significantly, a strong partial γ-fiber spreading from {111}﹤112﹥ or {554}﹤225﹥ to {111}﹤134﹥ and {114}﹤481﹥ are developed in steel sheet rolled at 20°C and 400°C, while a dominated η-fiber peaked at {310}﹤001﹥ is formed between surface and quarter thickness in steel sheet rolled at 600°C. The different recrystallization textures can be ascribed to the profuse shear band at 600°C compared with the microstructures at 20°C and 400°C.

Nowadays, diagnosis for epilepsy depends on many systems helping the neurologists to quickly find interesting segments from the lengthy signal by automatic seizure detection. However, we notice that it is very difficult, to obtain long-term EEG data with seizure activities for epilepsy patients in areas lack of medical resources and trained neurologists. Therefore, we propose to study automated epileptic diagnosis using interictal EEG data that is much easier to collect than ictal data. The research, therefore, aims to develop an automated diagnostic system that can use interictal EEG data to diagnose whether the person is epileptic. To develop such a system, we extract from the EEG data three classes of features which respectively are Petrosian fractal dimension, Higuchi fractal dimension and Hjorth parameters and build a Probabilistic Neural Network (PNN) fed with these features. Meanwhile, we also broach demand for data standardization by analysis with EEG of epileptic patients.

An information consensus algorithm for high-order multi-agent systems is proposed based on algebraic graph theory. Sufficient and necessary conditions are given for each information to converge to common values. The network topology of multi-agent systems has a directed spanning tree and each weight of different derivatives is positive, then consensus is achieved.

According to the principle of photovoltaic(PV) grid-connected generation, the maximum power point tracking (MPPT) and grid-connected control strategy were presented in this paper. Based on the V-I characteristic curve of photovoltaic array, it built the mathematic model of photovoltaic array and the MPPT algorithm. Through adopting the double-loop feedback control strategy, it achieved the unit power factor control. Lastly, with the example system, it implemented the simulations analysis including the sunlight changing and the temperature changing. The simulation results show that the proposed models and the control strategy are correct.

According to the Beijing-Zhuhai Expressway K421+642~K421+975 Subgrade disease problems, it is reinforced by dry mixed of cement rubble pile. In order to study the reinforcement effect, the test site is divided into 5 sections and each section has six piles, the length of pile is 6.0m, the diameter of pile is 150mm, the pile spacing is 1m×1m and the weight of hammer is 120Kg. The packing height of pile and the compaction number of pile per layer is different on each section. By analyzing the results of the loading tests and the dynamic penetration test, when the packing height is less than 40cm and the compaction number is more than 7, the pile body is closely dense state and bearing capacity characteristic value is 340Kpa, and meet the design requirements; The variation is comparative analyzed by the results of the CPT, Rayleigh wave test and laboratory tests of the reinforcement of subgrade before and after, the water content of reinforced subgrade is decreased, the subgrade bearing capacity and settlement is improved. Subgrade diseases have not been detected after they were treated one year. The analysis and control methods provide references for similar projects treatment.

Mismatch is one of the main defects of tailor welded blanks(TWB), and leveling technology is a new method which can solve this problem. The structures, force analysis and flange morphology of the leveling mechanism are studied in this paper, and a three-dimensional prototype is designed. The results have practical significance for improving welding quality of TWB.

Using the electrostatic spraying method to spray the epoxy coating on the surface of prestressing wire or strand. By this method, the mechanical properties can reach the same level of original prestressed steel, the anti-corrosion ability is superior to that of galvanized steel, and the epoxy coating not only does not have a negative impact on anchorage performance, but also improve the bond strength between wire and cold-cast filler. The LZM cable system using epoxy-coated wire and the OVM250 and GJ cable system using epoxy-coated strand have been developed and widely applied in China since the year of 2001.

Based on the bending experiment for two-span continuous beams of retard-bonded prestress concrete, the analysis of the stress increment of prestressed tendons is made in the loading process. The theory that the working performance of retard-bonded prestressed concrete members is as same as unbonded prestressed concrete members during the retarding period is demonstrated. It is feasible to use the formulas for the reference (Technical specification for concrete structures prestressed with unbonded tendons) to calculate σputhe ultimate stress and Δσp the Stress increment of the retard-bonded prestressed tendons and the recommended formulas are advised to use. It is also demonstrated that retard-bonded prestressed concrete members have the same working performance as bonded prestressed concrete members after the retarding period. The conclusion of this paper can provide the reference date for the design of retard-bonded prestressed concrete continuous beam.