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Motion modularity is the main method of motion control for higher animals. That means the complex movements of the muscles are made up of basic motion primitives, and the brain or central nervous system does not care about the specific details of the movement. However, the industrial robot control system does not adopt the technical roadmap of motion modularity, it generates complex trajectories by providing a large number of sampling points. This approach is equivalent to using the brain to directly guide the specific movement of the muscle and has to rely on a faster Fieldbus system to obtain complex motion trajectories. This work constructs a modularized industrial robot trajectory generation component based on Dynamic Movement Primitives (DMP) theory. With this component, the robot controller can generate complex trajectories without increasing the sampling points and can obtain good trajectory accuracy. Finally, the rationality of this system is proved by simulations and experiments.

An estimation method for inner temperature distribution of slow-wave structure is proposed without placing temperature sensors inside the traveling wave tube. The inner temperature distribution is estimated based on body temperatures, with Genetic BP Neural Network solving the thermodynamic parameters of the thermal model. The results showed that the method has good accuracy and feasibility.

The wear-resistant tin bronze (Cu-10Sn-4Ni-3Pb) with tin content above 8 wt.% prepared by traditional melting and casting process usually defects such as low density, poor properties and segregations. The crystallization under pressure processing of Cu-10Sn-4Ni-3Pb alloy was investigated. The microstructures were observed and analyzed and compared with that by traditional melting and casting process. The results show that the dendrite has obviously disappeared and the dendritic segregation alleviated by using the crystallization under 680 MPa pressure process, in comparison with the remarkably dendrite microstructure and severe as-cast defects of alloy prepared by traditional melting and casting technology. Based on the experimental study, the properties and microstructures of Cu-10Sn-4Ni-3Pb tin bronze prepared by crystallization under pressure have been improved significantly.

We demonstrate the characteristics of relatively low saturation intensity using co-doped Nd, Cr:YAG as saturable absorber for passively mode locking the Nd:YAG laser. The difference of the saturation intensity between Q-switched and mode-locked operation in co-doped Nd, Cr:YAG was only one to two orders of magnitude, while Cr:YAG was generally reported at a difference of five orders of magnitude. More than 80% mode locking modulation depth was achieved at an incident pump power of 4.4W, corresponding to an intracavity intensity of 6×104W/cm2, using a 68cm long plano-concave cavity.

We report for the first time on the observation of self-mode-locking in a diode pumped self-Q-switched (SQS) Nd3+,Cr4+:YAG laser. This phenomenon results from significant excited state absorption of the Cr4+ ions in the co-doped host during the SQS laser pulses. The self-mode-locking occurs already slightly above the SQS laser threshold. Experiments using relatively low saturable intensity achieved a modulation depth of more than 40%.

We carried out the operation of an intracavity frequency-doubled self-Q-switched Nd, Cr: YAG/KNbO3 946/473 nm microchip laser pumped by a Ti:sapphire laser. The overall cavity length was about 4 mm. The maximum average blue power of 12 mW was achieved with a repetition rate of 13 kHz at an absorbed pump power of 545 m W. The pulses of the 4 73 nm laser had a duration of 7 ns and a peak power of 132 W at this pump level. The conversion efficiency was 2.2% with respect to the absorbed pump power of a 808 nm laser.

Reliability of cathodes is critical for the reliability of traveling wave tubes. Accordingly, the reliability test and life prediction of diodes can provide useful information for cathode and TWT reliability evaluation. In this paper, a simple cathode life prediction method considering the evolving of heater power and perveance is presented. The method is applied on the reliability test data for some glass diode samples and several gun samples. The evaluation results show that the cathode life in the electron guns is much longer than those in the diode samples. And the cathode life prediction result for the diodes, based on the evolving of perveance and heater power for a certain anode current and voltage, is close to the final test result.

ObjectiveTo investigate whether 4-month preoperative lanreotide treatment would improve the surgical cure rate of newly diagnosed acromegalic patients with macroadenomas.DesignA prospective, randomised study.MethodsAfter a baseline evaluation, patients were randomly assigned to 4-month preoperative treatment with lanreotide (starting with 30 mg/2 weeks i.m. and increasing to 30 mg/week i.m. at week 8 if mean GH >2.5 μg/l on GH day curves; pretreatment group, Group 1) or to transsphenoidal surgery (direct surgery group, Group 2). Cure was evaluated 4 months postoperatively primarily by fasting IGF1 less than or equal to age-adjusted upper limit of normal.ResultsA pool of 108 patients was randomly divided into two groups. Five patients in each group were lost to follow-up during the study period, so 49 patients in each group were analysed. At baseline, no difference was observed between the two groups. Cure was established in 24 of 49 (49.0%, 95% confidence interval (CI), 35.0–63.0%) pretreated patients (Group 1) versus 9 of 49 (18.4%, 95% CI, 7.6–29.2%) direct surgery patients (Group 2;P=0.001). Surgical morbidity was recorded in 12 patients (12.2%) and was similar in Group 1 and 2 patients (14.3 and 10.2% respectively;P=0.538). The postoperative hospital stay was similar between groups: being 4.5±1.6 days in Group 1 vs 4.8±1.9 days in Group 2 (P=0.328).ConclusionsPretreatment with lanreotide before transsphenoidal surgery improves surgical cure rates in patients with GH-secreting pituitary macroadenomas. Pretreatment does not affect surgical complications or duration of hospital stay (ClinicalTrials.gov number, NCT00993356).