支持GPU的Flash3D技术

3D图形技术的应用早已十分广泛.随着互联网的发展,越来越多的应用被推广到互联网上,但涉及3D的应用却不多,近年来,多种新技术的发展给基于Web的3D图形技术注入了新的活力.本文主要研究了基于Adobe Flash平台的Web3D技术.首先介绍了Flash3D的工作原理,然后介绍了相关的一些3D引擎,最后基于其中的一个3D引擎研究了创建3D场景的一系列关键技术,并实现了一个演示范例.

Better prognostic determination of cT3 rectal cancer through measurement of distance to mesorectal fascia:A multicenter study

Objective:To forward the magnetic resonance imaging(MRI)based distance between the deepest tumor invasion and mesorectal fascia(DMRF),and to explore its prognosis differentiation value in cT3 stage rectal cancer with comparison of cT3 substage.Methods:This was a retrospective,multicenter cohort study including cT3 rectal cancer patients undergoing neoadjuvant chemoradiotherapy followed by radical surgery from January 2013 to September 2014.DMRF and cT3 substage were evaluated from baseline MRI.The cutoff of DMRF was determined by disease progression.Multivariate cox regression was used to test the prognostic values of baseline variables.Results:A total of 804 patients were included,of which 226(28.1%)developed progression.A DMRF cutoff of7 mm was chosen.DMRF category,the clock position of the deepest position of tumor invasion(CDTI)and extramural venous invasion(EMVI)were independent predictors for disease progression,and hazard ratios(HRs)were 0.26[95%confidence interval(95%CI),0.13-0.56],1.88(95%CI,1.33-2.65)and 1.57(95%CI,1.13-2.18),respectively.cT3 substage was not a predictor for disease progression.Conclusions:The measurement of DMRF value on baseline MRI can better distinguish cT3 rectal cancer prognosis rather than cT3 substage,and was recommended in clinical evaluation.

Ice rafting history and paleoceanographic reconstructions of Core 08P23 from southern Chukchi Plateau, western Arctic Ocean since Marine Isotope Stage 3

Multiproxy investigations have been performed on Core 08P23 collected from the Chukchi Plateau, the western Arctic Ocean, during the Third Chinese National Arctic Expedition. The core was dated back to Ma-rine Isotope Stage （MIS） 3 by a combination of Accelerator Mass Spectrometric （AMS） carbon-14 dating and regional core correlation. A total of five prominent ice-rafted detritus （IRD） events were recognized in MIS 2 and MIS 3. The IRD sources in MIS 3 are originated from vast carbonate rock outcrops of the Canadian Arctic Archipelago and clastic quartz in MIS 2 may have a Eurasian origin. Mostδ18O andδ13C values of Neogloboquadrina pachyderma （sinistral） （Nps） in Core 08P23 are lighter than the average values of surface sediments. The lighterδ18O andδ13C values of Nps in the two brown layers in MIS 1 and MIS 3 were resulted from meltwater events; and those in the gray layers in MIS 3 were caused by the enhanced sea ice formation. Theδ18O values varied inversely withδ13C in MIS 2 indicate that the study area was covered by thick sea ice or ice sheet with low temperature and little meltwater, which prevented the biological productivity and sea-atmosphere exchange, as well as water mass ventilation. The covaried light values ofδ18O andδ13C in MIS 1 and MIS 3 were resulted from meltwater and/or brine injection.

Yuanzheng 3 Upper Stage

Upper stage is an indispensable vehicle in the space transportation system.For its role in multi-satellite transportation area in China,the development of the Yuanzheng 3 upper stage was approved.The article introduces in detail the Yuanzheng 3 upper stage development requirements,task definition and systems as well as main features and performance including payload capacity and insertion accuracy for typical orbits,interfaces with satellites.The article also presents the development cycle of Yuanzheng 3 upper stage,which is divided into 3 stages including concept demonstration stage,prototype stage and flight proof stage.The Yuanzheng 3 upper stage,which will make its maiden flight in 2018,is capable of restarting more than 20 times,and operating for more than 48 hours.It is equivalent to mainstream upper stages in the world in terms of performance,such as restart times,in-orbit operation time,independent digital control system,and adaptable behavior for various tasks.Technologies tackled and accumulated in the development of the Yuanzheng 3 upper stage will lay a solid foundation for the development of future space transportation vehicles.

Flash应用程序在移动端的显示效率研究

移动端应用程序的开发目前很流行,但在丰富用户体验的要求下,其显示效率的优化是非常关键的。主要针对目前基于flash平台进行移动端应用程序开发的显示效率问题进行研究,并给出Blitting技术、Stage3D技术的实现原理、思路和效果分析,不同的实现方法有着不同的适用场合。

Soil Properties in Two Soil Profiles from Terraces of the Nam Co Lake in Tibet,China

This article investigates the soil properties in two soil profiles from the terraces of the Nam Co Lake in Tibet,China. Profile 1,with a slope aspect to east,is 37 m,and profile 2,to southwest,is 32 m above the lake level. Twelve and nine layers were identified in profile 1 and profile 2,respectively,based on the color,texture,structure,moisture content,presence of carbonate,and root density. Grain sizes and measurements of water content,total organic carbon,total inorganic carbon,total carbon,pH value and electrical conductivity were all analyzed for each sample. The results show that soil is poorly developed because of sparse vegetation coverage and weak chemical weathering in the cold and arid area. The results also indicate that the soil properties are different between the two profiles and suggest that soil is better developed in profile 1 than in profile 2. These differences are ascribed to the dissimilarity of landform,vegetation and timing. Profile 1 faces to east as compared with profile 2 facing to southwest and gets less insolation and therefore less evaporation. Thus,vegetation grows better in profile 1 than in profile 2. Radiocarbon dating and OSL dating show that profile 1 underwent a longer soil forming process than profile 2,which is helpful for the soil development in profile 1.

Evolution of sedimentary environments of the middle Jiangsu coast, South Yellow Sea since late MIS 3

An evolutionary model of sedimentary environments since late Marine Isotope Stage 3 （late MIS 3, i.e., ca. 39 cal ka BP） along the middle Jiangsu coast is presented based upon a reinterpretation of core 07SR01, new correlations between adjacent published cores, and shallow seismic profiles recovered in the Xiyang tidal channel and adjacent northern sea areas. Geomorphology, sedimentology, radiocarbon dating and seismic and sequence stratigraphy are combined to confirm that environmental changes since late MIS 3 in the study area were controlled primarily by sea-level fluctuations, sediment discharge of paleo-rivers into the South Yellow Sea （SYS）, and minor tectonic subsidence, all of which impacted the progression of regional geomorphic and sedimentary environments （Le., coastal barrier island freshwater lacustrine swamp, river floodplain, coastal marsh, tidal sand ridge, and tidal channel）. This resulted in the formation of a fifth-order sequence stratigraphy, comprised of the parasequence of the late stage of the last interstadial （Para-Sq2）, including the highstand and forced regressive wedge system tracts （HST and FRWST）, and the parasequence of the postglacial period （Para-Sql）, including the transgressive and highstand system tracts （TST and HST）. The tidal sand ridges likely began to develop during the postglacial transgression as sea-level rise covered the middle Jiangsu coast at ca. 9.0 cal ka BP. These initially submerged tidal sand ridges were constantly migrating until the southward migration of the Yellow River mouth to the northern Jiangsu coast during AD 1128 to 1855. The paleo-Xiyang tidal channel that was determined by the paleo-tidal current field and significantly different from the modern one, was in existence during the Holocene transgressive maxima and lasted until AD 1128. Following the capture of the Huaihe River in AD 1128 by the Yellow River, the paleo-Xiyang tidal channel was infilled with a large amount of river-derived sediments from AD 1128 to 1855, causing the emergence of some of the previously submerged tidal sand ridges. From AD 1855 to the present, the infilled paleo-Xiyang tidal channel has undergone scouring, resulting in its modern form. The modern Xiyang tidal channel continues to widen and deepen, due both to strong tidal current scouring and anthropogenic activities.

An early Cambrian Sidneyia(Arthropoda) resolves the century-long debate of its head organization

We report the extraordinarily preserved euarthropod Sidneyia minor sp.nov.from the Cambrian Stage 3 Xiaoshiba Lagerst?tte in Yunnan,South China.So far this is the earliest occurrence of the genus.As with other species of Sidneyia,the new taxon shares similar features such as a crescent-shaped head shield with paired lateral notches for stalked eyes,but more significantly and new,is the presence of three pairs of post-antennal appendages beneath the head shield identified by micro-CT methods.We conclude that Sidneyia is a sister group to other members of Vicissicaudata within the diverse radiation of Artiopoda.