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The atomic H-masers are widely used in time keeping nowadays. BIPM has changed clock frequency prediction method since September 2011 based on weighting the clocks according to their predictability. An H-maser characterized by a very significant frequency drift can be used in time keeping because its behavior can be well predicted. The clock ensemble of UTC(NIM) consists 6 H-masers (5 at the new campus) and 7 Cs clocks, an H-maser is chosen as the master clock. All the H-masers are model MHM-2010 made by Symmetricom. In order to verify whether the frequency drift of H-masers can be modified manually, some tests were performed and the results showed that the frequency drift of the MHM-2010 H-maser could be somehow modified by changing its Hydrogen pressure. The test procedure and the results are introduced in this paper.

Summary Microseismic location is the basic problem in microseismic monitoring.Currently there are two acquisition methods used in the industry for microseismic monitoring:downhole arrays and surface arrays.Furthermore,because of the low signalnoise ratio of microseismic data,complex underground structure, inaccurate velocity and other factors,each way of microseismic monitoring has its deficiencies.Although surface arrays has a higher lateral accuracy of the source, but lack of vertical information of the source results a lower hypocenter vertical accuracy,while downhole arrays has a higher vertical resolusion of the source but lack of lateral information of the source results a lower hypocenter lateral accuracy.Therefore,combining the two methods could improve the performance of the monitoring system.In this paper,we have researched the time-reverse location method with the interferometric imaging condition used the combined surface and downhole arrays.The imaging artifacts can be attenuated by this method and an improved location accuracy can be obtained through synthetic event modeling using elastic functions.

We assessed gene expression profiles in 2,752 twins, using a classic twin design to quantify expression heritability and quantitative trait loci (eQTL) in peripheral blood. The most highly heritable genes (~777) were grouped into distinct expression clusters, enriched in gene-poor regions, associated with specific gene function/ontology classes, and strongly associated with disease designation. The design enabled a comparison of twin-based heritability to estimates based on dizygotic IBD sharing and distant genetic relatedness. Consideration of sampling variation suggests that previous heritability estimates have been upwardly biased. Genotyping of 2,494 twins enabled powerful identification of eQTLs, which were further examined in a replication set of 1,895 unrelated subjects. A large number of local eQTLs (6,988) met replication criteria, while a relatively small number of distant eQTLs (165) met quality control and replication standards. Our results provide an important new resource toward understanding the genetic control of transcription.

In order to solve a problem of experience feeling in traditional electrical safety training, the Risk Experience System for electricity is designed based on ARM and ZigBee, this system puts emphasis on negative stimulation and reverse experiential training, and transmits the signal of switch, sensors and the state changes of security devices to ARM control board. It is sample information of electrical equipment and information of the insulated gloves and electric test pen with ZigBee by the way of wireless transmission, and then, this system analyses these information and outputs risk phenomena by physical simulation. If operational errors, the system will trigger a variety of simulated accident devices, resulting in highlight flash, smoke, explosion, and a strong electric shock feeling. By this way, the operator can understand the serious consequence that is caused by wrong operation more intuitively, and enhance the effect of training. It has been proved that the system can complete the function of risking experience successfully.

At NIM, one GPS carrier phase processing method exclusively for time and frequency transfer, GPSTFP, was developed. Using the method, we implemented the CCD and long baseline time and frequency transfer experiments for performance verification. We can acquire the good agreement among P3 results, GPSTFP results, and the ones by the professional GPS processing software. From one day data, the difference between the mean values of P3 and GPSTFP results was less than 0.5 ns and the time stability from the CCD experiment is about 100 ps.

Repairing the panel CAD geometric model is an important pre-processing step of the finite element analysis, and widely used in the computer-aided geometric design field. This paper focused on the surface healing method of panel CAD model, which was proposed and analyzed by NURBS technology. Through the pipeline method determines the matching-curves border fast firstly, make the curves discrete points sets and on the basis of the characteristics of the matching-curves method, the surfaces were stitched. On the basis of the algorithm, a surface stitching program module was developed. The validity of algorithm was verified by healing automobile front fender parts.

We obtained the slope efficiency of 20% and the maximum output energy of 5.3mJ by Nd3+ complex laser. To the best of knowledge, this is the highest slope efficiency in bulky lasers using Nd3+ complex.