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From flying dreams to programming pioneer
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作者 孙启禄 《疯狂英语(新读写)》 2025年第7期24-27,76,共5页
More than seventy years before airplanes were invented,a twelve⁃year⁃old girl named Ada Lovelace dreamed of flying.She studied birds and experimented with materials to make wings,even writing a guide called Flyology.B... More than seventy years before airplanes were invented,a twelve⁃year⁃old girl named Ada Lovelace dreamed of flying.She studied birds and experimented with materials to make wings,even writing a guide called Flyology.But her curiosity didnt stop there. 展开更多
关键词 GUIDE flyology ada lovelace programming pioneer FLYING
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Demographic performance and climate change response of a pioneer tree species(Pinus massoniana)during ecological restoration in subtropical China
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作者 Ao Liu Rong Liu +5 位作者 Feiya Lei Jiazheng Wang Yongwei Luo Bingqi Hu Shouzhong Li Xianyu Yang 《Journal of Forestry Research》 2025年第3期107-119,共13页
Climate change is expected to alter the popu-lation dynamics of pioneer tree species and their planned use in sustainable forest management,but we have a lim-ited understanding of how their demographic rates change in... Climate change is expected to alter the popu-lation dynamics of pioneer tree species and their planned use in sustainable forest management,but we have a lim-ited understanding of how their demographic rates change in response to climate changes during ecological restora-tion.Based on 12 years of demographic data for a pioneer tree species(Pinus massoniana)censused in three plots that correspond to three stages of ecological restoration in south-eastern China.We built integral projection models(IPMs)to assess vital rates(survival,growth,reproduction)and population growth in each plot,then evaluated demographic changes to simulated changes in seasonal mean temperature and precipitation in the current and previous census period.The plot representing the medium restoration stage had the highest population growth rate(λ=0.983).Mean population survival probability increased with ecological restoration,and reproduction probability was significantly suppressed at the high restoration stage.Survival is always the most important vital rate forλ,and climate affectsλprimarily via survival at each restoration stage.The current spring tem-perature was the most critical climate variable forλin the low and medium restoration stages,and previous summer temperature was most critical in the high restoration stage.Simulated warming leads to a decrease in the stochastic population growth rate(λ_(s))of P.massoniana in every stage.These findings suggest that during ecological restoration,P.massoniana responds to habitat change via modified demo-graphic performance,thus altering its response to climate change.Despite diverse responses to climate change,the persistence of P.massoniana populations is facing a wide-spread threat of warming states at each restoration stages. 展开更多
关键词 Climate change Demographic performance Ecological restoration Integral projection models pioneer tree species
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Visionary Pioneer Founding President of the Tianfu Association(Singapore)Du Zhiqiang:advancing win-win cooperation between China and Singapore
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作者 Huang Jiangqin Chen Xiaoran 《China Report ASEAN》 2025年第8期38-38,共1页
Against the backdrop of the 35th anniversary of China-Singapore diplomatic relations,Tianfu Association(Singapore)has emerged as a key force fostering closer people-to-people and economic ties between the two countrie... Against the backdrop of the 35th anniversary of China-Singapore diplomatic relations,Tianfu Association(Singapore)has emerged as a key force fostering closer people-to-people and economic ties between the two countries.Founded in January 2000 by a group of new immigrants from China’s Sichuan Province,the association was the first Chinese immigrant organization established after diplomatic ties were formed between Singapore and China.Over the past two decades,it has actively engaged in local affairs and now serves as a council member of the Singapore Federation of Chinese Clan Associations.Today,it is widely recognized as one of the most vibrant and influential new immigrant groups promoting integration into Singaporean society. 展开更多
关键词 pioneer win win cooperation economic ties tianfu association singapore China singapore diplomatic relations new immigrants people people ties founding president
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Pioneer3-AT上基于双目立体视觉的环境识别系统 被引量:4
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作者 杨洁 闫清东 《实验室研究与探索》 CAS 北大核心 2016年第2期102-106,共5页
针对研究用的平台——Pioneer3-AT的软硬件环境,结合基于双目立体视觉的环境识别过程、原理和实际的应用环境设计了一个双目立体视觉系统。根据经典图像传感器的特点、实际需求、要观测的视野大小、精度要求确定硬件参数,进而选择了两个... 针对研究用的平台——Pioneer3-AT的软硬件环境,结合基于双目立体视觉的环境识别过程、原理和实际的应用环境设计了一个双目立体视觉系统。根据经典图像传感器的特点、实际需求、要观测的视野大小、精度要求确定硬件参数,进而选择了两个CMOS摄像机,建立了几个可行的系统方案,并从中选定了一个符合本实验的方案。然后结合平台的结构和双目立体视觉系统实际的硬件技术要求,设计并制作了一个两层可水平放置两台摄像机的双目立体视觉实验或应用系统,最后加入了控制器——笔记本电脑构成了一个完整的环境识别系统。实验表明这个建立的试验系统比较实用。 展开更多
关键词 平台 pioneer3-AT 双目立体视觉 环境识别
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Pioneer移动机器人遥操作系统设计
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作者 刘欢 张毅 《微计算机信息》 北大核心 2008年第23期268-270,共3页
本文以ActivMedia公司的Pioneer 3-DX型移动机器人为控制对象,实现了一个可以通过Web浏览器远程访问和控制的移动机器人遥操作系统,该系统为研究人员和机器人爱好者提供了一个远程实验平台。
关键词 pioneer 移动机器人 INTERNET 遥操作
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pioneer3-AT机器人小车焊缝跟踪系统
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作者 魏复理 洪波 +2 位作者 屈岳波 尹力 来鑫 《现代焊接》 2008年第6期21-22,25,共3页
本文将pioneer3-AT机器人小车研究平台应用于焊缝跟踪的研究,设计了相应的焊缝跟踪系统,并对机器人小车进行了运动学分析;针对机器人小车的转弯控制与十字滑架的水平调节存在协调优化的问题,采用了模糊控制技术,取得了良好效果。
关键词 pioneer3-AT机器人小车 电弧传感器 焊缝跟踪 模糊控制
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Pioneer PDP-503HDC
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作者 叶新海 陈奕 简凝 《视听技术》 2004年第1期17-19,共3页
日本先锋公司在等离子显示领域,如同它所擅长的影碟机领域一样,也扮演着业界“先锋”的角色。在等离子技术问世并且正式产品面市初始.先锋就一直保持着先人一步的姿态。1997年,先锋推出了全球首部XGA显示精度的等离子显示器。同年... 日本先锋公司在等离子显示领域,如同它所擅长的影碟机领域一样,也扮演着业界“先锋”的角色。在等离子技术问世并且正式产品面市初始.先锋就一直保持着先人一步的姿态。1997年,先锋推出了全球首部XGA显示精度的等离子显示器。同年年底叉推出了全球首部供应消费市场的高清晰度50英寸等离子显示器。如今。先锋已经成为全球等离子显示板少数几个大型生产厂家之一, 展开更多
关键词 pioneer公司 PDP-503HDC 等离子显示器 菜单设置 性能 外形
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Pioneer 3机器人在基础教育技术课程研究性学习中的应用
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作者 黄捷 《福建教育学院学报》 2015年第1期80-83,共4页
文章研究机器人教育在基础教育技术课程研究性学习中的应用,培养学生控制与设计和计算机编程的综合能力。首先简要介绍了Pioneer 3机器人的体系结构及相关软件特点,然后以机器人路径规划及控制这一开放性问题开展研究性学习活动,并给出... 文章研究机器人教育在基础教育技术课程研究性学习中的应用,培养学生控制与设计和计算机编程的综合能力。首先简要介绍了Pioneer 3机器人的体系结构及相关软件特点,然后以机器人路径规划及控制这一开放性问题开展研究性学习活动,并给出了问题的解决方案。 展开更多
关键词 pioneer 3机器人 通用技术 信息技术 技术课程 控制与设计
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一类Pioneer-Climax模型的全局分歧 被引量:2
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作者 许丹丹 李艳玲 《安徽师范大学学报(自然科学版)》 CAS 北大核心 2010年第5期409-413,共5页
研究了一类带扩散项的Pioneer-Climax模型,运用分歧理论和度理论的知识,以扩散系数d为分歧参数,讨论了在一定条件下系统在正常数平衡态解附近的分歧现象,并给出了分歧点附近解的结构,且局部分歧可以延拓为全局分歧.
关键词 pioneer-climax模型 分歧理论 度理论
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Restoration potential of pioneer plants growing on lead-zinc mine tailings in Lanping, southwest China 被引量:14
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作者 Lei Dongmei Duan Changqun 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第10期1202-1209,共8页
This study focused on the restoration potential of ten pioneer plants (Artemisia roxburghiana, Artemisia tangutica, Carex inanis, Cyperaceae hebecarpus, Plantago depresa, Cynoglossum lanceolatum, Potentilla saundesian... This study focused on the restoration potential of ten pioneer plants (Artemisia roxburghiana, Artemisia tangutica, Carex inanis, Cyperaceae hebecarpus, Plantago depresa, Cynoglossum lanceolatum, Potentilla saundesiana, Coriaria sinica, Oxyria sinensis, and Miscanthus nepalensis) during the early phase of Pb-Zn mine tailings phytostabilization, in Lanping, China. The concentrations of heavy metals (Pb, Zn, and Cu) and soil fertility (the available N, P, K, and organic matter) in the rhizosphere of these spe... 展开更多
关键词 pioneer plant mine tailings PHYTOSTABILIZATION rhizosphere soil
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Wg signaling in Drosophila heart development as a pioneering model 被引量:2
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作者 Xiushan Wu The Center for Heart Development, Key Lab of MOE for Developmental Biology and Protein Chemistry, College of Life Sciences, Hunan Normal University, Changsha, 410081, China 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2010年第9期593-603,共11页
The heart is one of the first functional embryonic organs occurring during development. The fundamental developmental processes and genes involved in cardiogenesis are conserved between the invertebrates and vertebrat... The heart is one of the first functional embryonic organs occurring during development. The fundamental developmental processes and genes involved in cardiogenesis are conserved between the invertebrates and vertebrates. In the past fifteen years, one of signaling pathways that has been best characterized in heart development in both invertebrates and vertebrates is the Wg/Wnt signaling pathways. Since our discovery of the Wg signaling required for the early heart development in Drosophila, the past fifteen years have witnessed tremendous progress in the understanding of specific Wnt signaling pathways in vertebrate cardiogenesis. This review will summarize the current state of knowledge of Wg signaling transduction in Drosophila heart development, which will benefit our understanding of vertebrate cardiogenesis and human congenital malformations. 展开更多
关键词 heart development Wg/Wnt signaling pioneering model congenital malformations
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PIONEER PLANTS FOR ECOSYSTEM RECOVERY IN DRAINAGE BASIN OF ERLONGSHAN RESERVOIR IN HEILONGJIANG PROVINCE, CHINA 被引量:1
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作者 ZHANGXue-ping ZHANGYi CAOHui-cong 《Chinese Geographical Science》 SCIE CSCD 2004年第4期377-381,共5页
This article reveals the ecological features and the theories and methods of introducing pioneer plants in the process of eco-restoring in different degenerative ecosystems in the drainage basin of Erlongshan Reservoi... This article reveals the ecological features and the theories and methods of introducing pioneer plants in the process of eco-restoring in different degenerative ecosystems in the drainage basin of Erlongshan Reservoir in Heilongjiang Province by systemically studying the deteriorative ecosystems and using recovery theory. The study shows that with the rise in degenerative degrees of the ecosystems, bio-species and bio-diversity sharply decrease in the study area and microclimate becomes warmer and drier in natural ecosystem. Therefore, we must attach importance to the construction of plants and biodiversity. In the study, different pioneer plants are selected for different degenerative ecosystems to restore and maintain the service functions of the ecosystems. 展开更多
关键词 degenerative ecosystem pioneer plants BIODIVERSITY
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Roots of pioneer trees in the lower sub-tropical area of Dinghushan, Guangdong, China
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作者 HAO Yan-ru PENG Shao-lin +4 位作者 MO Jiang-ming LIU Xin-wei CHEN Zhuo-quan ZHOU Kai WU Jin-rong 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2006年第5期377-385,共9页
Representative pioneer tree root systems in the subtropical area of South China were examined with regard to their structure, underground stratification and biomass distribution. Excavation of skeleton roots and obser... Representative pioneer tree root systems in the subtropical area of South China were examined with regard to their structure, underground stratification and biomass distribution. Excavation of skeleton roots and observation of fine roots of seven species including the Euphorbiaceae, Theaceae, Melastomataceae, Lauraceae and Fagaceae families was carried out. The results showed that: (1) Pioneer tree roots in the first stage of natural succession were of two types, one characterized by taproot system with bulky plagiotropic branches; the other characterized by flat root system with several tabular roots. The late mesophilous tree roots were characterized by one obvious taproot and tactic braches roots up and down. Shrub species roots were characterized by heart fibrous root type featured both by horizontally and transversally growing branches. Root shapes varied in different dominant species at different stages of succession. (2) Roots of the different species varied in the external features-color, periderm and structure of freshly cut slash. (3) In a set of successional stages the biomass of tree roots increased linearly with the age of growth. During monsoon, the total root biomass amounted to 115.70 t/ha in the evergreen broadqeaved forest; 50.61 t/ha in needle and broad-leaved mixed forest dominated by coniferous forest; and 64.20 t/ha in broad-and needle-leaved mixed forest dominated by broad-leaved heliophytes, and are comparable to the underground biomass observed in similar tropical forests. This is the first report about roots characteristics of forest in the lower sub-tropical area of Dinghushan, Guangdong, China. 展开更多
关键词 pioneer tree Tree roots Lower subtropical forest Dinghushan China
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Chen Jiayong:Pioneer in hydrometallurgy and chemical engineering disciplines
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作者 Zai-Sha Mao Huizhou Liu Chao Yang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第1期2-5,共4页
Dr.Chen Jiayong(Chia-Yung)was born on Feb.17,1922 in a prestigous intellectual clan at Jintang County,Sichuan Province,China.After receiving early education at the Chengdu County Middle School(now Chengdu 7th School),... Dr.Chen Jiayong(Chia-Yung)was born on Feb.17,1922 in a prestigous intellectual clan at Jintang County,Sichuan Province,China.After receiving early education at the Chengdu County Middle School(now Chengdu 7th School),he was admitted as an undergraduate student to the Department of Chemical Engineering,the National Central University at the city of Chongqing from 1939 through 1943 during the Anti-Japanese War.After graduation,he continued to work as a teaching assistant for both the inorganic and organic chemistry courses. 展开更多
关键词 CHONGQING pioneer admitted
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万力推出“PIONEER先锋”概念轮胎 被引量:1
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作者 本刊编辑部 《橡胶科技》 2016年第2期50-50,共1页
广州丰力橡胶轮胎有限公司近期推出了以"绿色环保"为主打理念的概念轮胎——"PIONEER先锋"轮胎,成为国内率先推出概念轮胎的企业。"PIONEER先锋"概念轮胎以安全、环保、节能为主要推点,是首款新能源汽车专用的跑气保用轮胎。"PIO... 广州丰力橡胶轮胎有限公司近期推出了以"绿色环保"为主打理念的概念轮胎——"PIONEER先锋"轮胎,成为国内率先推出概念轮胎的企业。"PIONEER先锋"概念轮胎以安全、环保、节能为主要推点,是首款新能源汽车专用的跑气保用轮胎。"PIONEER先锋"轮胎胎面使用高性能胶料, 展开更多
关键词 轮胎胎面 pioneer 橡胶轮胎 汽车专用 首款 胎面花纹 普通轮胎 滚动阻力 抗湿滑性能 芳烃油
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Shaggy Rug Pioneer SRP92织机:织造优质毛绒地毯
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《纺织导报》 CAS 北大核心 2008年第8期71-71,共1页
在长毛绒地毯日益增长的市场需求的推动下,比利时Van de Wiele(范德纬尔)集团继Shaggy Ruge Xplorer织机在长毛绒地毯生产领域获得巨大成功之后,推出了其新型Shaggy Rug Pioneer SRP92地毯织机。Shaggy Rug PioneerSRP92织机可以采... 在长毛绒地毯日益增长的市场需求的推动下,比利时Van de Wiele(范德纬尔)集团继Shaggy Ruge Xplorer织机在长毛绒地毯生产领域获得巨大成功之后,推出了其新型Shaggy Rug Pioneer SRP92地毯织机。Shaggy Rug PioneerSRP92织机可以采用8色提花加工市场上非常普遍的绒高为2X50mm的长毛绒地毯或绒高为2X70mm的超长毛绒地毯(图1),其毛绒原料一般为热定形聚丙烯(卷曲或高捻度的)、聚酯、羊毛、棉等, 展开更多
关键词 pioneer 地毯织机 长毛绒 优质 织造 市场需求 VAN 比利时
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Park公司新建先进复合材料生产厂Pioneer Plant开业
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《热固性树脂》 CAS CSCD 2008年第2期18-,共1页
关键词 生产厂 先进复合材料 PARK pioneer Plant
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Pioneer DV—3310—S
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《电子科技》 2002年第2期47-47,共1页
关键词 pioneer DV-3310-S 先锋 DVD播放机
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Chen Nianzu,pioneer of medical popularization
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作者 Yongxuan Liang Yinghua Huang 《Journal of Traditional Chinese Medical Sciences》 CAS 2024年第1期1-2,共2页
Chen Nianzu,also known as Chen Xiuyuan and Chen Shengxiu(1573—1823)was from the Mei Village,Changle Xi,Fujian Province.He was a distinguished traditional Chinese medicine(TCM)theorist,clinician and educator of the Qi... Chen Nianzu,also known as Chen Xiuyuan and Chen Shengxiu(1573—1823)was from the Mei Village,Changle Xi,Fujian Province.He was a distinguished traditional Chinese medicine(TCM)theorist,clinician and educator of the Qing Dynasty and the author of the Three-Character Primer of Medicine(Yi Xue San Zi Jing),Versified Currrent Formulas(Shi Fang Ge Kuo),Briefly Annotated Treatise on Cold-induced Diseases(Shang Han Lun Qian Zhu),and Briefly Annotated Essentials fromthe Golden Cabinet(Jin Kui Yao Lue Qian Zhu),etc. 展开更多
关键词 Province. GOLDEN pioneer
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Pioneer Hi-Bred购进Native Plants的RFLP项目
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作者 王璋瑜 《生物技术通报》 CAS CSCD 1991年第11期17-17,共1页
Pioneer公司(Des Moines,IA)已从Native Plants Inc.(NPI)(Salt Lake City,UT)购得其限制性片段长度多态性(RFLP)项目.NPI原先是单纯的植物生物技术公司.此番交易使其业务范围漂移到植物衍生的杀虫剂.未公布交易的详细条款. 这种RFLP技... Pioneer公司(Des Moines,IA)已从Native Plants Inc.(NPI)(Salt Lake City,UT)购得其限制性片段长度多态性(RFLP)项目.NPI原先是单纯的植物生物技术公司.此番交易使其业务范围漂移到植物衍生的杀虫剂.未公布交易的详细条款. 这种RFLP技术(有时被称为指印分析),被用来定位并标记特异的植物基因.通过这一途径,育种者可以根据RFLP探针的出现来确定植物的性状,而不必进行费时的筛选.在植物育种工作者眼中,这项技术是改进传统植物育利工作、鉴别专利性材料以及追踪重要遗传性状的关键技术. 展开更多
关键词 pioneer Native Plants 植物基因 植物育种 专利性 植物生物技术 育种者 此番 战略性转移 原有客户
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