虚拟现实中基于图像绘制虚拟场景技术综述

虚拟环境漫游系统 ,传统上是采用计算机图形学原理建模来绘制虚拟场景。这种方法需要费时费力的建模和昂贵的专用绘制硬件。绘制质量和场景的复杂性常常因为实时要求而受到限制。最近几年 ,基于图像的绘制技术渐渐引起人们的兴趣。与传统的几何绘制技术完全不同 ,它是一种通过实景拍摄获取图像来表示虚拟场景的技术。全面介绍了基于图像绘制虚拟场景的发展历史、现状以及应用前景。深入地论述了所采用的方法和相关问题。     

从系统观整体性原则看科学技术学建设

系统观是对系统科学的概念、理论和方法进行高度抽象和概括的产物,目前已成为科学研究和技术开发中地位越来越重要的一种带有指导性的方法论。整体性原则是系统科学方法论的首要原则。本文从普遍存在的种类纷繁的系统中,抽象出科学技术学系统,通过探讨科学技术整体化发展趋势、系统整体与部分、系统内部部分与部分及系统整体与外部环境间的相互联系、相互作用论证了系统观整体性原则在科学技术学建设中的体现。     

完善现代农业金融支撑体系的实证研究——以长沙市为例

在现代农业建设背景下,从农村金融服务对象的视角,以问卷调研的方式,借助结构方程模型等统计方法,分析了长沙市周边地区农户对农村金融服务和金融环境的评价及其对金融期望的影响,总结了农村金融支撑体系完善路径.     

西宁市自然及人为因素与城市环境生态系统的作用机制

本文通过对西宁市地貌、气候、水文等自然因素及人类活动与环境生态系统的作用机制的研究，得知自然因素、人类活动，特别是人工地貌正在越来越大的程度上影响着城市环境生态系统，而这种或优或劣的影响所导致的反馈又作用于前者的演化，从而产生良性或恶性的循环。为西宁市的环保、城建等有关部门统筹规划，避免和改善自然和人为因素的不良效应，避免城市地貌灾害的发生，控制热岛效应，防治环境污染，提供有关理论依据。     

基于GIS的地下水环境信息系统

以遵义市海龙坝地下水资源管理为例，介绍了基于GIS的地下水环境信息系统的总体设计以及系统实现的功能。并以模糊综合评判模型为例，阐述了地下水环境评价与预测子系统所实现的评价和预测功能；另外，数据库管理子系统则实现了常规DBMS所具有的一切数据库管理功能。     

畜禽排泄物对环境的危害及处理进展

随着畜牧业的飞速发展,生产规模的扩大和集约化程度的提高,畜禽排泄物已成为重要的环境污染源之一。解决畜禽排泄物对环境的污染问题,也是保护生态环境的一项重要内容。作者对畜禽排泄物的危害、处理现状及无害化处理方式进行了讨论,认为利用畜禽粪便进行资源化有效利用、大力发展有机肥产业是解决大中型养殖企业产生的大量畜禽排泄物的有效途径,是实现畜牧业可持续发展的必由之路。     

Partitioning phenotypic variation: genotypic,environmental and residual components from bryozoan skeletal morphology

Using morphometric studies of colonial (clonal) organisms such as Bryozoa grown as replicates in controlled laboratory experiments, phenotypic variation (hard part morphology) can be partitioned into its genotypic and environmental (ecophenotypic) components. The interaction between these, i.e. different genotypic responses to the same environmental change, can also be recognized. Palaeobiological studies are inherently constrained by species concepts based on morphotypes (preserved morphological phenotype). Uncertainties associated with fossil species concepts restrict the deductive resolution potential of fossil taxa in discussions of the broader biological questions of species evolution, ecology, biogeography and phylogeny. The relationship between species-level morphological variation and genetic variation in modern taxa is central to evaluating the viability of fossil morphotypes as biological species. Results from a preliminary study of three genotypes of Electra pilosa L., grown as replicate colonies in tanks comprising different microenvironmental conditions, allow for direct evaluation of morphospecies concepts. Numerical analyses (Cluster Analysis, Principal Component Analysis and Two-way ANOVA) of six morphometric characters demonstrated a strong Genotype control over zooid morphology and limited environmental (Tank) effects with minimal environmental differences among tanks. No significant Genotype by Tank (=environment) interactions were found for any characters. These results demonstrate that it is possible to quantify the extent to which a given trait is plastically expressed in different environments. The strong degree of correlation between morphology and genetics for this species is encouraging for the use of morphotypes as proxies for biological species.     

Expanding the taxonomic conundrum: Three new species of groundwater crustacean (Syncarida,Bathynellacea, Parabathynellidae) endemic to the Iberian Peninsula

Two new species of the genus Iberobathynella and one new species of the cosmopolitan genus Hexabathynella are described from the Iberian Peninsula. The three new species were found in the groundwater of caves and the gravelly bank of a river, two species in the north of Spain (Cantabria and Burgos) and one in the south (Sevilla). The two new species of the genus Iberobathynella present a unique combination of characters. These character combinations for the species from Cantabria are: thoracopod 8 female with wrinkled cuticle and two teeth; seven spines on the furca; nine spines on the sympod, three barbed and one plumose seta on the exopod and two barbed setae on the endopod of the uropod; maxilla with 0, 0 and 15 setae on the three segments, respectively; five teeth on the pars incisiva and six teeth on the pars molaris of the mandible and seven segments on the antennule. The combinations of characters for the species from Burgos are: antennule with seven segments; segment 5 of the antennule with one aesthetasc; mandible with four and five teeth on the pars incisiva and pars molaris respectively; maxillule with one seta on segment 1 and 14 setae on segment 3; segment 1 of the endopod of the thoracopod 1 with two setae; uropod with six spines on the sympod, four barbed setae and one plumose seta on the exopod and no setae on the endopod; furca with five spines and the thoracopod 8 female with wrinkled cuticle and two teeth. This last species has an exclusive character for the genus: the absence of setae on the endopod of the uropod. The new species of the genus Hexabathynella has six spines of similar length on the sympod of the uropod (in all other species within the genus the distal spine is longer than the others); the form of the antennal organ in the males is shown to be a new unique character for the genus; the maxilla has three and 13 setae on segments 2 and 3, respectively; the uropod has six spines on the sympod, three barbed setae on the exopod and two smooth setae on the endopod, the endopod is twice as long as the exopod and the shape of the female thoracopod 8 is unique.     

南海问题中的日本因素与我国的安全环境

冷战期间日本承认中国对南海的主权,冷战后日本追随美国开始介入南海争端。新世纪,为维护其海上“生命线”安全的需要,保障其经济利益,争夺地区主导权并在钓鱼岛的主权问题和东海划界问题上牵制中国,日本开始介入南海争端,其战略措施有：舆论炒作“中国威胁论”;加强与亚太国家的合作并进一步巩固日美同盟,包括拉拢东南亚国家联盟、建立日越战略合作伙伴关系、加强与印度尼西亚和菲律宾的战略关系;从军事战略上谋划介入南海地区。日本介入南海争端意图推动南海问题的国际化,增加问题解决的难度,阻遏中国走向海洋的步伐,严重地威胁中国领海主权的完整。在解决南海争端的过程中,如何平衡日本因素是中国面临的一大挑战。     

汽车自动驾驶技术研究进展

人工智能和新一代信息技术的快速发展正推动汽车产品的智能化与网联化,以革命性的变化推动未来人们交通出行的变革。当前,在技术发展和产业探索实践的综合推动下,汽车自动驾驶成为现阶段汽车技术领域研究的重点和热点。基于此,重点围绕环境感知、路径规划与轨迹跟踪等汽车自动驾驶关键技术的发展和研究现状进行梳理和分析,为今后的自动驾驶相关研究提供参考。