Kalman filter-based model predictive control for drag-free satellite under actuator failures and input saturations.

This paper studies the problem of fault-tolerant control for the drag-free satellite subject to actuator failures and input saturations. Particularly, a new Kalman filter-based model predictive control method for the drag-free satellite is proposed. Based on the developed dynamic model and the Kalman filter strategy, a new fault-tolerant design scheme is presented for the challenging situation where the satellite is subject to measurement noise and external disturbance. With the designed controller, the robustness of the system can be guaranteed, and the problem caused by actuator constraints and faults can be solved. Finally, the correctness and effectiveness of the proposed method are verified by numerical simulations.

Robust Control Allocation for Space Inertial Sensor under Test Mass Release Phase with Overcritical Conditions.

This paper proposes a robust control allocation for the capture control of the space inertial sensor's test mass under overcritical conditions. Uncertainty factors of the test mass control system under the overcritical condition are analyzed first, and a 6-DOF test mass dynamics model with system uncertainty is established. Subsequently, a time-varying weight function is designed to coordinate the allocation of 6-DOF generalized forces. Moreover, a robust control allocation method is proposed to distribute the commanded forces and torques into individual electrodes in an optimal manner, which takes into account the system uncertainties. This method transforms the robust control allocation problem into a second-order cone optimization problem, and its dual problem is introduced to simplify the computational complexity and improve the solving efficiency. Numerical simulation results are presented to illustrate and highlight the fine performance benefits obtained using the proposed robust control allocation method, which improves capture efficiency, increases the security margin and reduces allocation errors.

Acupuncture combined with an antidepressant for patients with depression in hospital: a pragmatic randomised controlled trial.

OBJECTIVE: To assess the effectiveness of acupuncture combined with selective serotonin reuptake inhibitors (SSRIs) for patients with depression in hospital using a pragmatic randomised controlled trial. METHODS: 76 patients with depression were randomly divided into two groups (randomisation ratio 2:1 for treatment and control groups (CGs), respectively) and 71 patients completed the study. The 45 patients in the treatment group (TG) underwent acupuncture and received an SSRI and the 26 patients in the CG received an SSRI only. The 17-item Hamilton Depression Rating Scale (HDRS-17) was used to quantitatively assess patients after 1, 2, 4 and 6 weeks of treatment. RESULTS: The mean (SD) baseline total HDRS scores were 22.2 (0.60) and 22.1 (0.33) in the TG and CG, respectively. After the first week of treatment the HDRS score for the TG was reduced to 15.6 (0.81), significantly different from the score of 18.3 (0.55) for the CG, p<0.05. This significant difference was maintained to the end of the 6-week treatment period, when HDRS scores had fallen to 6.3 (0.49) and 8.2 (0.35) for the TG and CG, respectively. CONCLUSIONS: Acupuncture combined with an SSRI showed a statistically significant benefit for patients with depression in hospital over the 6-week period compared with SSRIs alone. This reduction in symptoms started in the first week and continued throughout the 6 weeks of treatment.

Safety and immunogenicity of a diphtheria, tetanus, acellular pertussis and Haemophilus influenzae Type b combination vaccine compared with separate administration of licensed equivalent vaccines in Chinese infants and toddlers for primary and booster immunization.

To evaluate the safety and immunogenicity of a diphtheria, tetanus, acellular pertussis and Haemophilus infuenzae Type b (DTaP/Hib) combination vaccine first developed by a Chinese manufacturer, a randomized, two-stage, parallel controlled, single center clinical trial was conducted in Dafeng, Jiangsu Province of China. A total of 720 infants were enrolled and randomly assigned to two groups with a 2:1 allocation. In Stage I, 480 subjects in Group T were administered with 3 doses of the DTaP/Hib vaccine at 3, 4 and 5 months of age, respectively, while 240 subjects in Group C received separate licensed DTaP vaccine and Hib conjugate vaccine on the same schedule. In Stage II, 633 primed toddlers (431 of Group T and 202 of Group C) were given a booster dose at 18 months of age. Sera samples were collected at pre-dose 1, 4 weeks post-dose 3, pre-dose 4 and 4 weeks post-dose 4, respectively. Levels of protective antibodies were measured by Enzyme Linked Immunoadsorbent Assay (ELISA). Immunogenicity was evaluated with regard to geometric mean concentrations (GMCs), seroconversion rates and seroprotection rates of the antibodies. Solicited adverse reactions were recorded for 3 days after each dose; unsolicited adverse events and serious adverse events were monitored for 28 days after vaccination. Results showed that seroconversion rates of anti-pertussis toxoid (PT), anti-filamentous hemagglutinin (FHA), anti-diphtheria toxoid (DT), anti-tetanus toxid (TT) and anti-polyribosyl-ribitol-phosphate (PRP) in Group T (Stage I: 98.06%, 97.33%, 100%, 100%, 98.79%; Stage II: 99.18%, 83.42%, 99.18%, 63.32%, 85.05%) were comparable to that of Group C (Stage I: 95.26%, 93.16%, 100%, 100%, 98.42%; Stage II: 98.89%, 83.89%, 98.33%, 53.89%, 76.67%). Nearly 100% of the subjects in both groups achieved seroprotective levels of anti-DT (> or = 0.1IU/ml), anti-TT (> or = 0.1IU/ml) and anti-PRP (> or = 0.15 microg/ml) after primary and booster vaccination. The frequencies of local induration, swelling and redness as well as general reactions such as fever, diarrhea and anaphylaxis were low and acceptable in both groups. In conclusion, the DTaP/Hib vaccine was demonstrated to be non-inferior to the control vaccines on safety and immunogenicity. There could be a bright future for the DTaP/Hib vaccine to be widely used in the universal vaccination of Chinese children.