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With the rapid development in civil aviation industry, the pilot is a lot of demand in short supply, which leads to high pressure on flight training. It is necessary to optimize the scheduling model for flight instructors and the urgency of the utilization of optimization techniques to realize flight instructor scheduling is increasingly significant. A fair and balanced scheduling model will take flight instructor’s willingness and flight duty time limitations into consideration. Therefore a multi-objective model of scheduling for flight training is provided,and the solution of the model is discussed.

Grey model GM(1,1) is applied to forecast flight training time. The discreteness of originality data is overcome and the high-precise predicted result is received under the condition of a small amount of data. This paper takes a short-term forecast flight training time of Civil Aviation Flight University of China (CAFUC) by using grey system theory. With a comparison of the actual data to the forecast result, it is proved that using grey system theory to forecast the flight training time of Civil Aviation Flight University of China is feasible with relatively high prediction accuracy.

The dynamic performance of the CNC turret affect the cutting capability and cutting efficiency of the NC machine tool directly, embody the core level of the design and manufacture of the NC machine tool. However, the dynamic performance of the CNC turret mostly decided by the dynamic performance of the power transmission system of the power turret. This passage use Pro/E to set the accurate model of the gears and the CAD model of the gear transmission system and based on this to constitute the ADAMS model of virtual prototype. On the many-body contact dynamics theory basis, dynamic describes the process of the mesh of the gears, work out the dynamic meshing force under the given input rotating speed and loading, and the vibration response of the gear system. The simulation result disclosure the meshing shock excitation and periodical fluctuation phenomena arose by stiffness excitation of the gear transmission. Analyses and pick-up the radial vibration response of the output gear of the gear transmission system as the feasibility analysis data.

Based on the computation method of reliability in limit state theory, the paper analyzes sensitivity of gear reliability with the change of various random factors. Taking the reliability computation of circular gear as an example, it systematically calculates the change of gear reliability with the change of average value and RMS error of random variables. Based upon the computed result, it analyzes and finds out sensible random factors that have larger influence on gear reliability for the convenience of strict control of gear design, manufacturing, use and maintenance in future in order to guarantee the requirement for gear reliability. Computed result in this paper can be used as reference for the study on gear reliability in future.

The paper studies on the gear reliability design method using probability finite element method based on response surface and it indicates that the reliability sensibility calculation method of function in response surface can be used when limit state function is unknown. The limit state function established on response function is quadratic polynomial with simple form and it makes the calculation of variance and deviation very convenient, which realizes the simple and easy calculation of reliability sensitivity and largely increases calculation velocity and precision. The method can be applied for general purpose with certain standard, which is easy for programming and accomplishing gear reliability design in a rapid and precise way.

Utilizing finite element software, an universal program has been worked out by the APDL, and it can output the heat dissipating capacity of appointed surfaces in analysis software. The program is so powerful that it can calculate the heat dissipating capacity of heat conductor in which the heat transfer two-dimensionally or three-dimensionally even if the heat conductor is anisotropic, which is difficult to calculate with the mathematic analysis method. The method mentioned in the paper can diminish the inaccuracy caused by the predigestion with the mathematic analysis method. The calculation principle of the program was introduced in detail. Comparing the result of the program with that got by mathematic method, it was indicated that the calculation error of program is very small.

Bt5198, a new rice restorer line containing Bt gene, was developed from the cross and backcross of the elite restorer line Chenghui 177 with Bt Minghui 63, a transgenic Bt restorer line. The inbred lines were evaluated using PCR amplification, test paper evaluation, insect resistance evaluation in both the laboratory and paddy fields, nursery evaluation of rice blast resistance and pedigree selection of agronomic traits. Larval mortalities on Bt5198 and Bt Minghui 63 were 100% when rice culms were inoculated with the eggs of the striped stem borer (SSB) in the laboratory. Bt5198 was highly resistant against SSB and the yellow stem borer (YSB) under field conditions. The F1 hybrids derived from Bt5198 and four cytoplasmic male sterile (CMS) lines were also highly resistant to SSB and YSB and had a significant heterosis. Two-year evaluation of rice blast resistance confirmed that the resistance levels of Bt5198 to leaf blast and neck blast were similar to those of Chenghui 177 and significantly better than those of Bt Minghui 63. Seed germination ability and pollen yield of Bt5198 were similar with Chenghui 177, suggesting that the introduction of the Bt gene into the new restorer line had no significant effects on seed vitality or the yield of seed production. To identify the presence of the Bt gene, it was effective to combine test paper examination with the evaluation of insect-resistance, both in the laboratory and under field conditions.

AIM To compare the efficacy of a session of extracorporeal shock wave lithotripsy (ESWL) before endoscopic retrograde cholangiopancreatography (ERCP) vs ERCP only for problematic and large common bile duct (CBD) stones. METHODS Adult patients with CBD stones for whom initial ERCP was unsuccessful because of the large size of CBD stones were identified. The patients were randomized into two groups, an “ESWL + ERCP group” and an “ERCP-only” group. For ESWL + ERCP cases, ESWL was performed prior to ERCP. Clearance of the CBD, complications related to the ESWL/ERCP procedure, frequency of mechanical lithotripsy use and duration of the ERCP procedure were evaluated in both groups. RESULTS There was no significant difference in baseline characteristics between the two groups. A session of ESWL before ERCP compared with ERCP only resulted in similar outcomes in terms of successful stone removal within the first treatment session (74.2% vs 71.0%, P = 0.135), but a higher clearance rate within the second treatment session (84.4% vs 51.6%, P = 0.018) and total stone clearance (96.0% vs 86.0%, P = 0.029). Moreover, ESWL prior to ERCP not only reduced ERCP procedure time (43 ± 21 min vs 59 ± 28 min, P = 0.034) and the rate of mechanical lithotripsy use (20% vs 30%, P = 0.025), but also raised the clearance rate of extremely large stones (80.0% vs 40.0%, P = 0.016). Post-ERCP complications were similar for the two groups. CONCLUSION Based on the higher rate of successful stone removal and minimal complications, ESWL prior to ERCP appears to be a safe and effective treatment for the endoscopic removal of problematic and large CBD stones.

AIM: To evaluate the effect of cholecystokinin (CCK) during extracorporeal shockwave lithotripsy (ESWL) in the clearance of common bile duct (CBD) stones in endoscopic retrograde cholangiopancreatography (ERCP). METHODS: Between January 2007 and September 2012, patients with large CBD stones who were treated with ESWL and ERCP were identified retrospectively. Patients were randomized in equal numbers to cholecystokinin (CCK) and no CCK groups. For each CCK case, a dose (3 ng/kg per min for 10 min) of sulfated octapeptide of CCK-8 was administered intravenously near the beginning of ESWL. ERCP was performed 4 h after a session of ESWL. The clearance rate of the CBD was assessed between the two groups. RESULTS: A total of 148 consecutive cases (CCK group: 74, no CCK group: 74) were tallied. Overall there were 234 ESWLs and 228 ERCPs in the 148 cases. The use of CCK showed a significantly higher rate of successful stone removal in the first ESWL/ERCP procedure (71.6% vs 55.4%, P = 0.035), but resulted in similar outcomes in the second (42.8% vs 39.4%) and third (41.7% vs 40.0%) sessions, as well as total stone clearance (90.5% vs 83.8%). The use of mechanical lithotripsy was reduced in the CCK group (6.8% vs 17.6%, P = 0.023), and extremely large stone (≥ 30 mm) removal was higher in the CCK group (72.7% vs 41.7%, P = 0.038). CONCLUSION: CCK during ESWL can aid with the clearance of CBD stones in the first ESWL/ERCP session. Mechanical lithotripsy usage was reduced and the extremely large stone (≥ 30 mm) clearance rate can be raised.