火炮射表数据处理方法评述

主要介绍火炮射表数据处理方法，对国内目前较为流行的两种射表逼近方法进行了全面、系统的分析与比较，指出了逐步回归射表逼近方法存在的缺陷和不足。对国外近几年采用的插值法文中也进行了比较详细的讨论，并指出了未来的研究问题。

火炮射表数据处理中几个有关问题的讨论

本文是文献的继续,主要研究射表数据处理中的几个技术问题。其中包括:自变量、逼近多项式的结构、项数和逼近精度的选择问题,以及广义正规方程组的解法、选项中的异常现象和贼点剔除问题等。它们是正确和有效进行射表数据处理的重要因素,是必须很好解决的问题。

火炮射表数据处理计算步骤和程序框图

本文是文献［１—３］的继续，主要研究火炮射表数据处理算法的计算步骤和程序设计框图。这两个内容是正确进行程序设计、分析和使用的重要环节。

一种快速高精度的射表数据处理方法

介绍一种基于多结点样条函数的射表数据处理新方法。与弹道方程法和多项式函数逼近法的比较结果表明，本方法兼有快速、高精度和实现简便等优点。

基于射表数据的火炮射击诸元解算方法研究

依据现有射表数据,采用插值方法建立出多组数据对应关系,通过火炮坐标和目标坐标计算出炮目距离和炮目方向,获得表尺改变量和方向改变量计算表尺和方向。选用某自行火炮的某型弹射表为实验数据,对基于射表数据的火炮射击诸元解算方法进行仿真验证。结果表明,基于射表数据的火炮射击诸元解算方法的解算精度和解算速度满足技术指标要求。

基于射表数据反算弹道的分析

针对利用射表数据很难直接得出弹道轨迹的问题,根据某炮的射表数据和射击诸元数据计算出该射击诸元情况下的弹道轨迹。利用射表数据所得的射表拟合逼近函数,通过目标命中点得到的射击诸元信息,反算出此射击诸元情况下的弹道轨迹,并利用根据射表求出的弹道分析射击脱靶量。运用MATLAB数值仿真软件,对弹道轨迹以及脱靶量进行计算分析。仿真结果快速计算出弹道轨迹,并验证了该想法的可行性与实用性。

Multi-SPline Technique for the Extraction of Drag Coeffidents from Radar Data

In the preparation of firing tables, the determination of projectile drag coefficientsthrough firing test radar data reduction is very important. Many methods have been developed for this work but none of them appear to be satisfactory in one Way or another. Inthis paper a multi-spline model of drag coefficient (cd) curve is developed that can guaranteefirst derivative continuity of the cd curve and has good flexibility of fitting accurately to acd curve from subsonic up to supersonic range. Practical firing data reduction tests showboth fast convergence and accurate fitting results. Typical velocity fitting RMS errors are0.05-0.08 m/s.

Validation of Global Land Surface Satellite (GLASS) Downward Shortwave Radiation Product in the Rugged Surface

The downward shortwave radiation(DSR) is an essential parameter of land surface radiation budget and many land surface models that characterize hydrological,ecological and biogeochemical processes.The new Global LAnd Surface Satellite(GLASS) DSR datasets have been generated recently using multiple satellite data in China.This study investigates the performances of direct comparison approach,which is mostly used for validation of surface insolation retrieved from satellite data over the plain area,and indirect comparison approach,which needs a fine resolution map of DSR as reference,for validation of GLASS DSR product in time-steps of 1 and 3 hours over three Chinese Ecosystem Research Network sites located in the rugged surface.Results suggest that it probably has a large uncertainty to assess GLASS DSR product using the direct comparison method between GLASS surface insolation and field measurements over complex terrain,especially at Mt.Gongga 3,000 m station with root mean square error of 279.04 and 229.06 W/m2in time-steps of 1 and 3 hours,respectively.Further improvement for validation of GLASS DSR product in the rugged surface is suggested by generation of a fine resolution map of surface insolation and comparison of the aggregated fine resolution map with GLASS product in the rugged surface.The validation experience demonstrates that the GLASS DSR algorithm is satisfactory with determination coefficient of 0.83 and root mean square error of 81.91W/m2over three Chinese Ecosystem Research Network sites,although GLASS product overestimates DSR compared to the aggregated fine resolution map of surface insolation.

Northward expansion of the western Pacific Warm Pool in late 1990s and early 2000s

Based on 48-year (1958-2006) ocean reanalysis data of Simple Ocean Data Assimilation and 23-year (1984-2006) global ocean-surface heat flux products developed by the Objectively Analyzed Air-Sea Heat Flux Project, meridional variation of the western Pacific Warm Pool (WPWP) is addressed. The results show that there is a significant expansion of the northern edge of the WPWP in the late 1990s and early 2000s. This variation is mainly within 120°E-160°E by 8°N-20°N, we define this region (120°E-160°E by 8°N-20°N) as the core region. Furthermore, analyses on upper ocean heat budget show that the short wave radiation plays a key role in the northward expansion of the northern edge of the WPWP in the core region. It is proved that the northward expansion may be caused by the change of the mixed layer which became shallower in 1994-2006 compared with 1984-1993 in the study region. The short wave radiation flux distribution within the shallower mixed layer leads to a positive anomaly in seawater temperature, promoting the northward expansion of the WPWP.

Intercomparison of Surface Radiative Fluxes in the Arctic Ocean

Recent satellite data analysis has provided improved data sets relevant to the surface energy budget in the Arctic Ocean. In this paper, surface radiation properties in the Arctic Ocean obtained from the Surface Radiation Budget（SRB3.0） and the International Satellite Cloud Climatology Project（ISCCP-FD） during 1984– 2007 are analyzed and compared. Our analysis suggests that these datasets show encouraging agreement in basin-wide averaged seasonal cycle and spatial distribution of surface albedo; net surface shortwave and all-wave radiative fluxes; and shortwave, longwave, and all-wave cloud radiative forcings. However, a systematic large discrepancy is detected for the net surface longwave radiative flux between the two data sets at a magnitude of ~ 23 W m–2, which is primarily attributed to significant differences in surface temperature, particularly from April to June. Moreover, the largest difference in surface shortwave and all-wave cloud radiative forcings between the two data sets is apparent in early June at a magnitude of 30 W m–2.

Influence of Global Solar Radiation on Indoor Environment： Experimental Study of Internal Temperature Distribution in Two Test Cells with Different Roof Systems

This work is part of a large experimental study on the distribution of internal temperatures in two similar test cells, but with different systems of coverage. The main goal of this paper is to present results on an experimental field to determine the influence of solar radiation on the internal environmental conditions of different roof systems. Dry bulb temperature and internal surface temperatures were measured in two test cells with different roof systems （green roof and conventional ceramic roof）. Their thermal performances were compared on days with differing air mass domain, based on dynamic climatic approach. This research was based on the spatial and temporal approaches of dynamic climatology, from the climatic regime of the city of Itirapina, S^o Paulo State, analysed as representative episodes. Climatic data were provided by an automatic weather station and verified by satellite imagery, and the internal temperatures of the cells were collected by thermocouples installed on the surfaces of ceilings, floors, walls, and suspended inside the buildings. The results indicate that the solar radiation is mainly responsible for the great variations in temperature and its impact on indoor environments, since there were great differences in temperature inside comparing the two days of the experiment. This refutes the notion that the outside temperature is responsible for daily variations in temperature inside buildings.

Retrieval of aerosol optical depth over bright targets in the urban areas of North China during winter

Two factors that affect satellite retrieval of Aerosol Optical Depth(AOD) are aerosol model assumptions and the separation of surface reflectance.NASA/MODIS Dense Dark Vegetation(DDV) algorithm has been proven valuable in deriving aerosol distribution and properties over land;however,it cannot be applied to bright targets.As a supplement to the DDV algorithm,an algorithm to retrieve AOD over urban areas in North China in winter is developed using MODIS data,including(1) the generation and analysis of adjacent clear-days surface reflectance using MOD09 product from 2007 to 2008,and(2) seasonal aerosol models derived from AERONET data in Beijing and Xianghe sites.Ground-based measurements using sun photometers were used to validate the retrieved AOD,and the correlation coefficient(r) is up to 0.931.Especially for high AOD values(AOD>0.4),more retrievals meet the inversion accuracy.The temporal variations of retrieval errors over urban,rural and mountain regions were examined,and the results indicated that the variation of blue-band surface reflectance is less than 0.02 in a short period except for unusual weather conditions,the retrieval bias is under 0.08,and the relative error decreases as the AOD increases.

An unexpected tetranuclear Li_2Cr_2 trimethylsilylacetylide complex bridged by two μ_3-pyrazolates

A tetranuclear Li2Cr2 acetylide precursor complex, [Li(Tp)crm(c=CSiMe3)2(/,t3-pz)]2· (n-pentane)2 (Tp = hydridotris(pyra- zolyl)borate, pz = pyrazolate) (1) has been synthesized and characterized. The X-ray structure analysis shows that the complex contains a Li2Cr2 core bridged by two ,u3-pyrazolates. The magnetic data exhibit the existence of weak antiferromagnetic in- teraction in the cluster.

Calibration of ASTER and ETM + Imagery Using Empirical Line Method——A Case Study of North-East of Hajjah, Yemen

This study is aimed at using the Empirical Line Method （ELM） to eliminate atmospheric effects with respect to visible and near infrared bands of advanced spaceborne thermal emission and reflection radiometer （ASTER） and enhanced thematic mapper plus （ETM＋） data. Two targets （Amran limestone as light target and quartz-biotite-sericite-graphite schists as dark target）, which were widely exposed and easy to identify in the imagery were selected. The accuracy of the atmospheric correction method was evaluated from three targets （vegetation cover, Amran limestone and Akbra shale） of the surface reflectance. Analytical spectral devices （ASD） FieldSpec3 was used to measure the spectra of target samples. ETM＋ data were less influenced by the atmospheric effect when compared to ASTER data. Normalized differences vegetation indices （NDVI） displayed good results with reflectance data when compared with digital number （DN） data because it is highly sensitive to ground truth reflectance （GTR）. Most of the differences observed before and after calibration of satellite images （ASTER and ETM＋） were absorbed in the SWlR region.