Radiation energy flux of Dirac field of static spherically symmetric black holes

By the statistical entropy of the Dirac field of the static spherically symmetric black hole, the result is obtained that the radiation energy flux of the black hole is proportional to the quartic of the temperature of its event horizon. That is, the thermal radiation of the black hole always satisfies the generalised Stenfan--Boltzmann law. The derived generalised Stenfan--Boltzmann coefficient is no longer a constant. When the cut-off distance and the thin film thickness are both fixed, it is a proportional coefficient related to the space--time metric near the event horizon and the average radial effusion velocity of the radiation particles from the thin film. Finally, the radiation energy fluxes and the radiation powers of the Schwarzschild black hole and the Reissner--Nordstrõm black hole are derived, separately.     

A multi-directional ground filtering algorithm for airborne LIDAR

Automatic ground filtering for Light Detection And Ranging (LIDAR) data is a critical process for Digital Terrain Model (DTM) and three-dimensional urban model generation. Although researchers have developed many methods to separate bare ground from other urban features, the problem has not been fully solved due to the similar characteristics possessed by ground and non-ground objects, especially on abrupt surfaces. Current methods can be grouped into two major categories: neighborhood-based approaches and directional filtering. In this study, following the direction of the second branch, we propose a new Multi-directional Ground Filtering (MGF) algorithm to incorporate a two-dimensional neighborhood in the directional scanning so as to prevent the errors introduced by the sensitivity to directions. Besides this, the MGF algorithm explores the utility of identifying pattern varieties in different directions across an image. The authors conducted a comprehensive test of the performance on fifteen study sites and compared our results to eight other publicized methods based on the Kappa coefficients calculated from the error matrices reported by ISPRS. Overall, the MGF filter produces a promising performance in both urban and forest areas. The size and shape of non-ground objects do not pose significant influence on the performance of the MGF algorithm. The fact that MGF algorithm is robust to two commonly required parameters, slope and elevation difference thresholds, has added practical merits to be adopted in different landscapes.     

Comparative analysis of relationships between NLDAS‐2 forcings and model outputs

This study reports results from an analysis of the relationship between atmospheric forcing and model‐simulated water and energy fluxes for the North American Land Data Assimilation System Project Phase 2 (NLDAS‐2). The relationships between mean monthly precipitation and total runoff are stronger in the Sacramento (SAC) and variable infiltration capacity (VIC) models, which grew out of the hydrological community, than in the Noah and Mosaic models, which grew out of the soil‐vegetation‐atmosphere transfer (SVAT) community. The reverse is true for the relationship between mean monthly precipitation and evapotranspiration. In addition, surface energy fluxes in VIC are less sensitive to model forcing (except for air temperature) than those in the Noah and Mosaic model. Notwithstanding these general conclusions, the relationships between forcings and model‐simulated water and energy fluxes for all models vary for different seasons, variables, and regions. These findings will ultimately inspire a combination of SVAT‐type model energy components with hydrological model water components to develop a SVAT‐hydrology model to improve both evapotranspiration and total runoff simulations. Copyright © 2011 John Wiley & Sons, Ltd.     

复合片取心钻头的研制及其应用

由金刚石共晶体与硬质合金基座制成的复合体是一种新型超硬研磨材料，用它和特制的钻头胎体制成的复合片取心钻头适用于可钻性小于Ⅶ级岩石的钻进，它的应用可大大提高煤系地层（特别是煤心）的采取率。     

Study on Inclusions in Natural and Synthetic Gems

The characteristics of inclusions in natural and synthetic gems are distinct owing to their different forming mechanisms and can be utilized to distinguish gems from different localities.In addition,intensive studies on inclusion characteristics of natural gems could identify their geographical origins and provide valuable information on gem synthesis,In this paper synthetic gems (synthetic star-spangled sapphire and emerald)and natural gems from various locations including natural sapphire from Thailand and Australia,and natural aquamerine from Mufushan,Hunan Province,and Ailoshan,Yunnan Province,were selected for the comparative study of inclusion.Significant research results have been achieved,thus providing the important basis for distinguishing natural from synthetic gems.     

LN-GDXT-1型多功能电源的研制

引言我国地震系统数字化台网改造工作正在全面展开 ,不仅需要高质量的数字化地震观测仪器 ,提高观测质量 ;同样也需要一种适合遥测台工作特点的供电系统 ,提高遥测台地震观测仪器的连续运行率。在遥测台网的监测工作中 ,由于原有的电源不尽完善 ,不能完全适应遥测台的工作环境 ,造成地震信号断记的现象时有发生。一直是困扰遥测台网监测工作质量的一个难题。为此 ,我们研制了 LN-GDXT-1型多功能电源。LN-GDXT-1型多功能电源具有性能稳定 ,输入交流电压范围宽 ,停电时持续供电时间长 ,免维护等特点 ,是一种较为理想的遥测台供电系统。1…     

用GMS—5气象卫星资料遥感监测白天雾的研究

用日本GMS－5静止气象卫星的可见光通道和长波红外通道的资料，采用多通道合成和图像增强技术生成云雾彩色图像，分析了云雾的纹理特征、运动规律和消散规律，探讨了白天雾和低层云的遥感监测和识别方法，对沪宁高速公路沿线大雾进行了实时监测。     

Discrimination Between Foreshocks and Earthquake Swarm from the Change of First Motion Sign

Based on the data of first motion of 11 earthquake sequences with ML ≥ 3.0 recorded by the Telemetric Seismic Network of Shanxi since the 1980s, the first motion characteristics of each earthquake sequence were studied. It is known that earthquake sequences of different types have different consistency characteristics of focal mechanism. The decrease and increase of the first motion contradictory sign ratios could be taken as an index to judge whether there would still be a larger earthquake to come after the earthquake sequence.     

Activity Feature of Kazkeaerte Fault Zone in the Late Quaternary

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