检索结果-南通市图书馆

在线全文

学校读者我要写书评

暂无评论

三维虚拟动画设计中的角色建模与行为控制

现代电子技术 2020年第10期43卷 108-110页

作者：于兵科西京学院陕西西安710123

针对传统三维虚拟动画模型方法中行为控制数据点识别水平低下的问题,设计一种三维虚拟动画设计中的角色建模与行为控制方法。采用动力学方式,以物理引擎为基础,建立角色骨骼模型,并采用ODE开源物理引擎模拟关节运动轨迹,完成效果的实时... 详细信息

针对传统三维虚拟动画模型方法中行为控制数据点识别水平低下的问题,设计一种三维虚拟动画设计中的角色建模与行为控制方法。采用动力学方式,以物理引擎为基础,建立角色骨骼模型,并采用ODE开源物理引擎模拟关节运动轨迹,完成效果的实时渲染。实验结果表明,与传统方法相比,所提方法在角色行为控制的过程中所采集到的数据点更加密集,动画效果更加逼真,具有极高的有效性及优越性。

关键词：三维虚拟动画动画设计角色建模行为控制实时渲染仿真实验

在线全文

学校读者我要写书评

暂无评论

基于虚拟现实的三维动画立体空间设计

现代电子技术 2021年第8期44卷 49-52页

作者：于兵科西京学院陕西西安710123

针对传统三维动画设计无法得到精准坐标数值的问题,该文提出虚拟现实技术下的三维动画设计和应用研究。计算像素点坐标值,利用数值微分画线算法,得到像素点所组成的直线段微分方程,获取最终输出值组成图像元素;使用虚拟现实技术,转换为... 详细信息

针对传统三维动画设计无法得到精准坐标数值的问题,该文提出虚拟现实技术下的三维动画设计和应用研究。计算像素点坐标值,利用数值微分画线算法,得到像素点所组成的直线段微分方程,获取最终输出值组成图像元素;使用虚拟现实技术,转换为立体表达方式,构建三维虚拟场景;根据视角差原理,采用摄像机模拟人眼成像效果,实现基于虚拟现实技术的三维动画设计。仿真实验结果表明,与传统设计方法相比,该文所提出的三维动画设计将虚拟现实技术应用到三维动画设计能有效提高精准坐标数值和弥补传统设计缺陷,使三维动画的设计与后期修改工作更加准确快捷。

关键词：三维动画设计虚拟现实技术立体表达三维场景构建仿真实验效果分析

在线全文

学校读者我要写书评

暂无评论

基于VOF-DPM耦合的Y型喷嘴雾化研究

化学工程 2024年第8期52卷 78-83页

作者：刘汉勇冯胜科李兵科谭永华虞育松山东华鲁恒升化工股份有限公司山东德州253024 北京航天动力研究所北京100076 航天推进技术研究院陕西西安710100 北京交通大学机械与电子控制工程学院北京100044

采用VOF-DPM(流体体积-离散相模型)耦合方法的数值模拟,研究液体黏度对Y型喷嘴内流动和喷嘴雾化性能的影响。首先对Y型喷嘴内部和外部区域进行多面体网格划分,并借助基于气液体积分数值的自适应网格加密技术有效提高气液界面识别精度。... 详细信息

采用VOF-DPM(流体体积-离散相模型)耦合方法的数值模拟,研究液体黏度对Y型喷嘴内流动和喷嘴雾化性能的影响。首先对Y型喷嘴内部和外部区域进行多面体网格划分,并借助基于气液体积分数值的自适应网格加密技术有效提高气液界面识别精度。分析喷嘴内流动与喷嘴外雾化的关联,研究液体黏度对雾化性能的影响。结果表明:重油黏度较高,流速较小,喷嘴内重油不易被气体吹散和掺混,液体雾化较难。柴油密度低于重油,易被加速,导致喷雾贯穿距离大于重油,雾化更容易,柴油的喷雾锥角与重油差距不大。重油的喷雾索特平均直径d s为137.14,略高于柴油d s约0.8%。研究对评估燃烧器燃烧性能及其适应多种燃料的改造设计具有重要的应用价值。

关键词： VOF-DPM耦合数值模拟液体黏度 Y型喷嘴雾化性能

Research on the dry intrusion accompanying the low vortex precipitation

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2007年第9期50卷 1396-1408页

作者： YAO XiuPing1,2,3, WU GuoXiong1, ZHAO bingke4, yu yuBin3 & YANG GuiMing2,5 1 LASG, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China 2 Institute of Heavy Rain, China Meteorological Administration, Wuhan 430074, China 3 China Meteorological Administration Training Center, Beijing 100081, China 4 Shanghai Typhoon Institute of China Meteorological Administration, Shanghai 200030, China 5 National Meteorological Center of the China Meteorological Administration, Beijing 100081, China LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Institute of Heavy Rain China Meteorological Administration Wuhan 430074 China China Meteorological Administration Training Center Beijing 100081 China LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Shanghai Typhoon Institute of China Meteorological Administration Shanghai 200030 China China Meteorological Administration Training Center Beijing 100081 China Institute of Heavy Rain China Meteorological Administration Wuhan 430074 China National Meteorological Center of the China Meteorological Administration Beijing 100081 China

By employing the 6.7μm satellite vapor cloud images and NCEP/NCAR 1°×1° reanalysis datasets, the characteristics and mechanism of the dry intrusion, as well as its impacts on the low vortex precipita- tion at the Meiyu front are explored in this paper. It is found that the formation,development and main- tenance of the low vortex precipitation at the Meiyu front are closely related to the evolution of the dry intrusion. The dry intrusion is characterized by high potential vorticity (PV), low humidity and cold air. The dry intrusion exhibits as an obvious dark zone on vapor cloud images, an area in which atmos- pheric relative humidity is lower than 60%. However, the features of the dry intrusion on the vapor im- ages are clearer than that of the humidity field, for the former is the digital vapor cloud images with high temporal and spatial resolution, and it can be used to explore the finer characteristics of the develop- ment, evolution and supplement of the intrusion during the development of the low vortex. The dry intrusion impacts accompanying the low vortex precipitation at the Meiyu front come from all levels of the troposphere, with the strongest intrusion located at the upper troposphere. The dry and cold air intrudes the vicinity of the low vortex from the upper isentropic surface to the lower one, slanting eastward from lower to higher level. The low vortex precipitation region is usually situated in front of the dry intrusion where the relative humidity gradient is higher. The research also reveals that the mechanism of the dry intrusion is that the high potential vorticity descends from the upper troposphere to the lower level, therefore, the dry intrusion can be used as an important index of the high PV forcing. To the west of the low vortex precipitation, the upper level northerlies descend across the isentropic surface, then the dry cold advection can trigger the instable development in the mid-low troposphere. The dry intrusion enhances the low vort

关键词： Meiyu front, low vortex precipitation, dry intrusion, mechanisim, vapor image, potential vorticity, relative humidity

Western North Pacific Tropical Cyclone Database Created by the China Meteorological Administration

在线全文

学校读者我要写书评

暂无评论

Advances in Atmospheric Sciences 2021年第4期38卷 690-699页

作者： Xiaoqin LU Hui yu Ming YING bingke ZHAO Shuai ZHANG Limin LIN Lina BAI Rijin WAN Shanghai Typhoon Institute China Meteorological AdministrationShanghai 200030China Key Laboratory of Numerical Modeling for Tropical Cyclone/China Meteorological Administration Shanghai 200030China

This paper describes the access to, and the content, characteristics, and potential applications of the tropical cyclone(TC) database that is maintained and actively developed by the China Meteorological Administration, with the aim of facilitating its use in scientific research and operational services. This database records data relating to all TCs that have passed through the western North Pacific(WNP) and South China Sea(SCS) since 1949. TC data collection has expanded over recent decades via continuous TC monitoring using remote sensing and specialized field detection techniques,allowing collation of a multi-source TC database for the WNP and SCS that covers a long period, with wide coverage and many observational elements. This database now comprises a wide variety of information related to TCs, such as historical or real-time locations(i.e., best track and landfall), intensity, dynamic and thermal structures, wind strengths, precipitation amounts, and frequency. This database will support ongoing research into the processes and patterns associated with TC climatic activity and TC forecasting.

关键词： tropical cyclone multi-source database western North Pacific

台风条件下火箭探测气象数据与ERA5再分析资料的对比分析

在线全文

学校读者我要写书评

暂无评论

热带气象学报 2024年第3期40卷 526-536页

作者：郑一赵兵科陈勇航刘琼刘统强宋金轲魏鑫魏煜罗维婷东华大学环境科学与工程学院上海201620 中国气象局上海台风研究所上海200030

再分析资料的准确性对台风等灾害性天气预报及研究有着重要价值。以往缺乏在强台风条件下平流层内的直接观测资料,使得无法对再分析资料的准确性进行验证,基于新型火箭探测数据对ERA5再分析数据的气象要素在强台风条件下进行对比分析。... 详细信息

再分析资料的准确性对台风等灾害性天气预报及研究有着重要价值。以往缺乏在强台风条件下平流层内的直接观测资料,使得无法对再分析资料的准确性进行验证,基于新型火箭探测数据对ERA5再分析数据的气象要素在强台风条件下进行对比分析。(1)台风条件下三次试验ERA5与火箭探测在对流层内的温度廓线几乎重合,15 km以下两者之间的误差不到1℃,但15 km以上的平流层两者偏差随高度增加而增大,ERA5比火箭探测的温度明显偏低,在15~20 km、20~30 km、30~40 km和40 km以上两者偏差平均值分别为3.75℃、5.52℃、14.41℃和19.25℃;(2)相对湿度三次试验两者的变化趋势还是比较相似的,但在平流层低层15~20 km两者存在较大差异,火箭探测相对湿度在15 km左右是上干下湿分界高度,而ERA5的分界高度抬升到20 km以上,也就是说ERA5把高湿度层抬升了5 km以上;值得一提的是25 km以上,台风影响前,两者相对湿度都几乎接近0%,而在台风影响期间火箭探测相对湿度可达5%左右,ERA5相对湿度仍然几乎为0%;(3)台风条件下三次试验风速廓线显示两者在平流层低层到对流层变化趋势十分相似,相关系数可达0.85左右,平均偏差大约为2 m·s^(-1);而在平流层中高层相似度降低,偏差增大,相较于火箭探空,ERA5风速偏低4 m·s^(-1)左右。

关键词： ERA5 台风火箭温度相对湿度风速

嵌套高分辨率网格对我国东南沿海登陆台风模拟的影响

在线全文

学校读者我要写书评

暂无评论

东华大学学报（自然科学版） 2024年第2期50卷 181-189页

作者：邬贤文陈勇航魏煜郑运霞孙琳琳马骁骏辛渝赵兵科刘海晨李金乐李纤宁东华大学环境科学与工程学院上海中国气象局上海台风研究所上海复旦大学大气与海洋科学系上海中国气象局乌鲁木齐沙漠气象研究所新疆乌鲁木齐中山大学海洋工程与技术学院广东珠海

嵌套高分辨率网格对台风模拟有十分重要的影响。基于COAWST(coupled ocean atmosphere wave sediment transport)模式,针对登陆广东、海南的11个台风,设计了2组模拟方案。一组是在9 km分辨率下嵌套3 km分辨率网格,另一组是采用单层9 km... 详细信息

嵌套高分辨率网格对台风模拟有十分重要的影响。基于COAWST(coupled ocean atmosphere wave sediment transport)模式,针对登陆广东、海南的11个台风,设计了2组模拟方案。一组是在9 km分辨率下嵌套3 km分辨率网格,另一组是采用单层9 km分辨率网格。将模拟结果与中国气象局热带气旋资料中心发布的最佳路径数据进行对比,以探讨嵌套高分辨率网格是否可以提高台风模拟的准确性。从台风路径的模拟结果来看,在9 km分辨率下嵌套3 km分辨率网格对台风路径模拟的误差较小,而单层9 km分辨率网格模拟的台风路径误差较大。通过对比两组方案模拟的台风路径、强度和结构,在模拟区域中使用嵌套高分辨率网格方案的模拟准确性有所提高。两种方案模拟的风场以及副热带高压十分接近。相比于单层网格,嵌套了高分辨率网格方案模拟的台风路径、强度误差更小,台风眼更小,位涡更强。

关键词：高分辨率网格台风模拟 COAWST模式台风路径台风强度台风结构

石灰施用与种肥播施方式对红壤旱地芝麻生育期和产量的影响

在线全文

学校读者我要写书评

暂无评论

安徽农学通报 2024年第12期30卷 30-33页

作者：万长艳王馨悦陈明熊文余跑兰黄天宝应治宏高冰可肖鸿勇江西省红壤及种质资源研究所江西南昌330046 九江市农业科学院江西九江332101 江西省农业技术推广中心江西南昌330046

为明确红壤旱地芝麻适宜的种植方式,本研究在两个不同种植区开展石灰施用、不同播种施肥方式对芝麻产量的影响试验。结果表明,不同种植区的芝麻生育期存在差异;种植区和石灰施用对株高无明显影响;不同种植区、石灰施用和播种施肥方式对... 详细信息

为明确红壤旱地芝麻适宜的种植方式,本研究在两个不同种植区开展石灰施用、不同播种施肥方式对芝麻产量的影响试验。结果表明,不同种植区的芝麻生育期存在差异;种植区和石灰施用对株高无明显影响;不同种植区、石灰施用和播种施肥方式对单株蒴数有明显影响,且种植区和播种施肥方式间存在一定的互作效应;各处理中,施用石灰、采用条播和侧深施肥处理的产量较高。生产中,红壤旱地芝麻种植在保证一定密度的前提下,可通过增施石灰,采用条播和侧深施肥方式提高产量。

关键词：芝麻石灰红壤旱地测深施肥芝麻产量

维普期刊数据库博看期刊

Analysis of genetic architecture and favorable allele usage of agronomic traits in a large collection of Chinese rice accessions

在线全文

学校读者我要写书评

暂无评论

Science China(Life Sciences) 2020年第11期63卷 1688-1702页

作者： Xiuxiu Li Zhuo Chen Guomin Zhang Hongwei Lu Peng Qin Ming Qi Ying yu bingke Jiao Xianfeng Zhao Qiang Gao Hao Wang yunyu Wu Juntao Ma Liyan Zhang Yongli Wang Lingwei Deng Shanguo Yao Zhukuang Cheng Diqiu yu Lihuang Zhu Yongbiao Xue Chengcai Chu Aihong Li Shigui Li Chengzhi Liang State Key Laboratory of Plant Genomics Institute of Genetics and Developmental BiologyInnovation Academy for Seed DesignChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Biotechnology Research Institute Heilongjiang Academy of Agricultural SciencesHarbin 150086China Rice Research Institute State Key Laboratory of Crop Gene Exploration and Utilization in Southwest ChinaSichuan Agricultural UniversityChengdu 611130China Lixiahe Agricultural Research Institute of Jiangsu Province Yangzhou 225009China Jiangsu Collaborative Innovation Center for Modern Crop Production Nanjing 210095China State Key Laboratory for Conservation and Utilization of Bio-Resources in yunnan Yunnan UniversityKunming 650091China

Genotyping and phenotyping large natural populations provide opportunities for population genomic analysis and genome-wide association studies(GWAS). Several rice populations have been re-sequenced in the past decade;however, many major Chinese rice cultivars were not included in these studies. Here, we report large-scale genomic and phenotypic datasets for a collection mainly comprised of 1,275 rice accessions of widely planted cultivars and parental hybrid rice lines from China. The population was divided into three indica/Xian and three japonica/Geng phylogenetic subgroups that correlate strongly with their geographic or breeding origins. We acquired a total of 146 phenotypic datasets for 29 agronomic traits under multi-environments for different subpopulations. With GWAS, we identified a total of 143 significant association loci, including three newly identified candidate genes or alleles that control heading date or amylose content. Our genotypic analysis of agronomically important genes in the population revealed that many favorable alleles are underused in elite accessions, suggesting they may be used to provide improvements in future breeding efforts. Our study provides useful resources for rice genetics research and breeding.

关键词： rice Chinese cultivars whole-genome resequencing multi-environmental phenotyping genome-wide association studies favorable alleles