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By taking the National Ignition Facility(NIF) from the USA and the Laser Megajoule(LMJ) from the France for examples,this paper analyzes the general layout and general structure engineering features of Inertial Confinement Fusion(ICF) laser facility.NIF is designed with a U-shaped building layout,and it not only can provide an optimum laser experimental equipment configuration but also allow the equipment to attach a second target chamber in future.The bundles of LMJ are arranged in an in-line building.Its layout decreases the optical path-length between the output of each beamline and the focusing system also provides an option for a second target chamber exists.The paper suggests that the general layout of an ICF laser facility should meet the requirements of the physical experimental purposes and should be characterized by operation stability,good integration and higher maintainability.Furthermore,it should design convenient interfaces for future development.In overall design of the equipment,optical elements are packaged into a optical-mehanical assemblies,and replaceable units(LRUs) are assembled with kinematic mounts.The general structure of ICF design should match the arrangement of the laser beams in structural layout and configuration.Moreover,the structure design can not dispense with the function,stability and cleanliness.The assignments of general structure design should meet the requirements of the installation and localization,integration and debugging,operation and maintenance of the optical components and the physical/optical diagnostic equipment.

Ardeidae and their habitat are being threatened by the destruction of wetland ecosystems.Because the availability of suitable Ardeidae habitats are gradually decreasing,habitat suitability evaluations using remote sensing and measurement technology are becoming research hotspots.In this study,Mai Po and the Deep Bay Area in Hong Kong was chosen as a case study area.Based on descriptive waterfowl statistics from field observation data,we used Moran′s index to assess spatial autocorrelation.The results of this analysis indicated that the field data was randomly distributed within the study area,and that there were no duplicate records.Therefore the data was suitable for modeling.We used a logistic regression model to determine the factors associated with the waterfowls′ habitat.First,according to Ardeidae habitat dependencies,we collected data of 15 factors relevant to the waterfowl in January 2003 using Geographic Information System(GIS) and Remote Sensing technology.We randomly selected 1000 points from each factor′s grid map and used the leverage value and cook distance method to look up unusual points.Few unusual points were identified,and most of the selected points were able to be used to establish the binary logistic regression model.Nine factors were identified by the model as having an important influence on the presence/absence of Ardeidae.These factors were land use,Normalized Difference Vegetation Index,slope,rainfall,TM 4 texture,TM 3 texture,road density,road distance,and human habitation density.The Nagelkerke R2 verified that the model was a good fit(coefficient =0.774).Aspect,digital elevation,human habitation distance,TM 2 texture,relative humidity,and temperature were simultaneously filtered out of the model,suggesting that the waterfowls′ habitat preferences were not influenced by these factors.We then used a quick clustering method to grade habitat suitability,and found that the case area could be divided into five levels.From a two figure stack in GIS,we selected 500 points from the Ardeidae population.We found that the prediction data from the binary logistic regression model was in good agreement with the observed field data of Ardeidae waterfowl in this area,with a kappa coefficient of 0.774.We suggest that the suitability grades basically correspond with the waterfowls′ habitat,and that we could predict the presence of waterfowl with the model.The model could also be used to estimate the presence of waterfowl in unstudied areas that are difficult to access.The model has better application prospects in studies of wetlands.Finally,we used January,2009 data of the nine significant factors in Mai Po and the Deep Bay Area to test the universality of the model′s equation.We followed the same steps as for the 2003 data,and the fitting accuracy reached a kappa coefficient of 0.758.The results of our study show that the binary logistic regression model could be used for forecasting Ardeidae waterfowl habitat suitability.We demonstrate the effectiveness of correlation analyses for predicting waterfowl habitat.Our model performed well in the prediction of the presence of Ardeidae waterfowl,and provides a reference for the protection and management of waterbird habitats,and for future studies.

A method called "wavelet packet approach to sub-band decomposition independent component analysis" was introduced to unmix hyperspectral mixed pixels.Using wavelet packet decomposition technique to improve independent component analysis,a blind unmixing method for hyperspectral data was proposed considering the characteristics of hyperspectral data,and this method could overcome the drawback derived from statistical independence assumption in independent component analysis.Two groups of synthetic data and three groups of indoor data were used to evaluate this method.The experiments show that spectra and fractional abundances of the endmemebers can be retrieved precisely using the proposed method,and its accuracy is significantly higher than that of independent component analysis.This approach is useful for blind unmixing of hyperspectral remotely sensed imagery.

To assure the pointing accuracy in a shooting target to be better than 30 μm for the Shen Guang Ⅲ(SGⅢ)facility,the switchyard of target area for the facility was designed and the rigid frame and transport mirrors in the switchyard were optimized to improve their stability.In design,the reinforced concrete was used to support the switchyard,and the tilted supports were added in the steel frame of switchyard to decrease and distribute the mass load reasonably.Furthermore,the herringbone supports were firmed to local horizontal beams.The transport mirror supports were also designed,in which their foundational frequencies were much higher than that of the swichyard.By above ways,the angle shifts of transmission mirrors in random broadband vibration can be suppressed successfully.The mechanical analysis of range structure by Finite Element Analysis(FEA) indicates that 87% of transport mirrors show their angle shifts less than 0.48 μrad.According to the relation between the rotation drifts of the optics components and the positioning errors of optical path,it can be seen that the rotation drifts of the transmission mirrors could meet the stability requirements for the positioning error of each single optical path not more than 12.9 μm.

The development of a novel push-type ultrasonic endoscope is described in which probe rotation is accomplished by a small motor situated near the transducer. A digital FPGA-based ultrasound imaging system is implemented which uses coded excitation to increase the SNR and penetration depth, with probe rotation accomplished by a small motor situated near the transducer replacing the external motor and the long steel wire used in other ultrasonic endoscopes. The apparatus is tested continuously for 300 hours with no obvious problems. The coded excitation, digital quadrature demodulation imaging system can obtain ultrasonic images of higher quality and more information of the echo is preserved compared with the analog imaging system, because the analog digital conversion is moved to the first step of the signal processing.The digital imaging system possesses a higher SNR resulting in a sharp image. Locating the motor near the probe improves the consistency of rotational speed in comparison with external guide-wire rotation, and increases the image quality and life-span of these devices.

The AlGaInAs semiconductor saturable Absorber grown by Metal-organic Chemical Vapor Deposition is used as the saturable Absorber in a 808 nm LD-pumped passively Q-switched Nd∶YVO4 laser at 1.06 μm.The dependences of the pulse energy,pulse width,pulse repetition rate on the pumping power are measured.With an incident pump power of 10.57 W,an average output power of 3.4 W is obtained,and the corresponding slope efficiency is 39%.At this pump power,the repetition rate reaches the maximum value of 101 kHz.The Q-switched pulse width reaches the minimum of 1.76 ns with an incident pump power of 8.07 W.Using the rate equations of passively Q-switched lasers,the theoretical results for the pulse energy,pulse width,pulse repetition rate are obtained,which show an agreement with the experimental results on the whole.

Based on the comprehensive study of core samples, well testing data, and reservoir fluid properties, the construction and the distribution of the abnormal pressure systems of the Huatugou oil field in Qaidam Basin are discussed. The correlation between the pressure systems and hydrocarbon accumulation is addressed by analyzing the corresponding fluid characteristics. The results show that the Huatugou oil field as a whole has low formation pressure and low fluid energy; therefore, the hydrocarbons are hard to migrate, which facilitates the forming of primary reservoirs. The study reservoirs, located at the Xiayoushashan Formation (N21) and the Shangganchaigou Formation (N1) are relatively shallow and have medium porosity and low permeability. They are abnormal low-pressure reservoirs with an average formation pressure coefficient of 0.61 and 0.72 respectively. According to the pressure coefficient and geothermal anomaly, the N1 and N21 Formations belong to two independent temperature-pressure systems, and the former has slightly higher energy. The low-pressure compartments consist of a distal bar as the main body, prodelta mud as the top boundary, and shore and shallow lake mud or algal mound as the bottom boundary. They are vertically overlapped and horizontally paralleled. The formation water is abundant in the Cl− ion and can be categorized as CaCl2 type with high salinity, which indicates that the abnormal low-pressure compartments are in good sealing condition and beneficial for oil and gas accumulation and preservation.