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At present, tight oil reservoir is a hot spot in the field of oil and gas development, and the effective development of such reservoir needs reservoir evaluation as a guide. Based on the experimental research on the core of tight oil reservoir of Chang7 member in Zhidan area, combined with the method of statistics and numerical simulation, eight parameters of “sand thickness, crude oil viscosity, main throat radius, starting pressure gradient, clay mineral content, rock brittleness index, percentage of movable fluid and reservoir pressure coefficient” are selected, and then, the new method of tight oil reservoir evaluation is obtained after normalizing the each parameter. Through this method, the tight oil reservoir of Chang7 member in Zhidan area can be divided into Class I, Class II and Class III, of which Class I and Class II reservoirs currently have certain development value. When development this kind of tight oil reservoir, large-scale hydraulic fracturing is required, which may affect or destroy the existing original forest protection area, water resource protection area and farmland. Therefore, after considering the environmental safety factors, the reservoir is classified and evaluated, and the development block is selected.

An optimization method of heart sound feature combination based on binary particle swarm optimization (BPSO) is proposed to analyze hypertrophic cardiomyopathy (HCM), which is a typical cardiovascular disease. The analysis procedure mainly includes feature extraction, feature combination optimization and HCM analysis. Firstly, 13-dimension energy features are extracted by the wavelet transformation. Secondly, feature combinations are selected by the proposed optimization method for classifying the normal and HCM heart sounds as well as the different types of HCM heart sounds. Lastly, 362 clinical cases including normal and HCM heart sounds are used to verify the validity of the proposed optimization method for heart sound feature combination, compared with principle component analysis (PCA), genetic algorithm (GA) and the analysis method without optimization of heart sound features. The average accuracy by our proposed optimization method, considering the number of features selected out, reaches to 20.91%, higher than the results utilizing feature combinations obtained by the other methods. In addition, the proposed optimization method of feature combination has potential for analyzing different kinds of HCM cases.

A three-stage W-band GaN monolithic microwave integrated circuit power amplifier (MMIC PA) is reported. Electron-beam lithography has been employed to define a 100-nm T-shaped gate on the AlGaN/GaN HEMT structure with ultrahigh aluminum content. The MMIC PA offers a peak small signal gain of 16.7 dB in the 90–97 GHz bandwidth. Moreover, it achieves a peak 1.66-W (32.2 dBm) output power at 93 GHz in a continuous-wave mode, with an associated power added efficiency of 21% and an associated power gain of 13.7 dB. Most notably, the peak power density is 3.46 W/mm with a 480- $\mu \text{m}$ wide output stage, which exceeds 3 W/mm in AlGaN/GaN HEMT at W-band for the first time.

A balanced four-stage W-band GaN MMIC PA with Lange couplers and micro-strips matching elements is reported. Electron-beam lithography has been used to produce a 100 nm T-shaped gate on the AlGaN/GaN HEMT structure with ultrahigh aluminum content. The MMIC PA offers a small signal gain of greater than 18 dB and an output power of greater than 2.5W from 88GHz to 93GHz with an associated power gain of greater than 15 dB. Moreover, it achieves a peak output power of 3.1W (34.9dBm) at 91GHz in continuous-wave mode, with an associated power density of 3.23W/mm. Most notably, it is the first time that the peak output power and power density exceed 3W and 3W/mm in AlGaN/GaN HEMT at W-band simultaneously.

Absolute test is one of the most important and efficient techniques to saperate the reference surface which usually limits the accuracy of test results. For the position error correction in absolute interferometry tests based on rotational and translational shears, the estimation algorithm adopts least-squares technique to eliminate azimuthal errors caused by rotation inaccuracy and the errors of angular orders are compensated with the help of Zernike polynomials fitting by an additional rotation measurement with a suitable selection of rotation angles. Experimental results show that the corrected results with azimuthal errors are very close to those with no errors, compared to the results before correction. It can be seen clearly that the testing errors caused by rotation inaccuracy and alignment errors of the measurements can be consequently eliminated from the differences in measurement results by the proposed method.

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.

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.

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.

Nd3+ complex doped polymer liquid laser have been demonstrated and the threshold of the laser was also calculated. The calculation results that a laser media with 2 mm length is suitable for low threshold laser oscillation. We obtained the slope efficiency of 20% and the maximum output energy of 5.3 mJ at the pumping energy of 31 mJ by the method of the side pumping. To the best of knowledge, this is the highest slope efficiency of the bulky laser using Nd3+ complex.