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Characterizing Potential Fishing Zone of Skipjack Tuna during the Southeast Monsoon in the Bone Bay-Flores Sea Using Remotely Sensed Oceanographic Data 被引量:3
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作者 Mukti Zainuddin Alfa Nelwan +4 位作者 Siti Aisjah Farhum Najamuddin   Muhammad A. Ibnu Hajar Muhammad Kurnia Sudirman   《International Journal of Geosciences》 2013年第1期259-266,共8页
Potential fishing zones for skipjack tuna in the Bone Bay-Flores Sea were investigated from satellite-based oceanography and catch data, using a linear model (generalized linear model) constructed from generalized add... Potential fishing zones for skipjack tuna in the Bone Bay-Flores Sea were investigated from satellite-based oceanography and catch data, using a linear model (generalized linear model) constructed from generalized additive models and geographic information systems. Monthly mean remotely sensed sea surface temperature and surface chlorophyll-a concentration during the southeast monsoon (April-August) were used for the year 2012. The best generalized additive model was selected to assess the effect of marine environment variables (sea surface temperature and chlorophyll-a concentration) on skipjack tuna abundance (catch per unit effort). Then, the appropriate linear model was constructed from the functional relationship of the generalized additive model for generating a robust predictive model. Model selection process for the generalized additive model was based on significance of model terms, decrease in residual deviance, and increase in cumulative variance explained, whereas the model selection for the linear model was based on decrease in residual deviance, reduction in Akaike’s Information Criterion, increasing cumulative variance explained and significance of model terms. The best model was selected to predict skipjack tuna abundance and their spatial distribution patterns over entire study area. A simple linear model was used to verify the predicted values. Results indicated that the distribution pattern of potential fishing zones for skipjack during the southeast monsoon were well characterized by sea surface temperatures ranging from 28.5℃ to 30.5 ℃ and chlorophyll-a ranging from 0.10 to 0.20 mg·m-3. Predicted highest catch per unit efforts were significantly consistent with the fishing data (P 2 = 0.8), suggesting that the oceanographic indicators may correspond well with the potential feeding ground for skipjack tuna. This good feeding opportunity for skipjack was driven the dynamics of upwelling operating within study area which are capable of creating a highly potential fishing zone during the southeast monsoon. 展开更多
关键词 Skipjack Tuna Satellite Data Generalized Additive Model Linear Model Upwelling Potential FISHING Zones BONE BAY and flores SEA Southeast MONSOON
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考虑球面副间隙的4-SPS/CU并联机构动力学分析 被引量:33
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作者 王庚祥 刘宏昭 《机械工程学报》 EI CAS CSCD 北大核心 2015年第1期43-51,共9页
基于机械系统动力学方程的增广法建立考虑球面副间隙的4-SPS/CU并联机构动力学模型。为了简化该并联机构的动力学模型,通过质量矩的方法视驱动支链为一个整体。根据含间隙球面副元素的接触方式建立该间隙运动副的运动学模型,求出含间隙... 基于机械系统动力学方程的增广法建立考虑球面副间隙的4-SPS/CU并联机构动力学模型。为了简化该并联机构的动力学模型,通过质量矩的方法视驱动支链为一个整体。根据含间隙球面副元素的接触方式建立该间隙运动副的运动学模型,求出含间隙球面副元素之间的接触变形量与相对接触速度。考虑到接触体之间接触刚度与机械系统动力学模型之间的耦合性,以非线性刚度系数代替Flores接触模型中的常数刚度系数而提出一种改进的接触力模型,并基于该接触力模型利用接触变形量与相对法向接触速度建立间隙运动副元素之间的法向接触力模型,为了保证数值运算的稳定性,采用具有动态修正系数的Coulomb摩擦模型,建立接触体之间的切向接触力模型。进一步把间隙运动副元素之间的接触力转换到该间隙运动副所连接的驱动支链和上平台的质心上,并把该接触力集成到4-SPS/CU并联机构动力学模型的广义力中,从而成功引入了关节间隙效应,采用Baumgarte稳定约束法避免了积分过程中的约束违约问题。通过数值分析预测球面副间隙对4-SPS/CU并联机构动力学性能的影响。 展开更多
关键词 4-SPS/CU并联机构 球面副间隙 flores接触模型 Coulomb摩擦模型 动力学
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不同修剪时期对杜鹃花花期的影响 被引量:3
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作者 张艳红 《北方园艺》 CAS 北大核心 2007年第3期118-119,共2页
以开花时间不同的杜鹃花为试材,研究了不同时期修剪对杜鹃花生长和开花的影响。试验结果表明:修剪可以使早、中花型的杜鹃花花期短期延后,对晚花型的杜鹃花影响甚微。修剪过早,株型不整齐;过晚影响开花的数量和质量。
关键词 杜鹃花 修剪 花期
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含间隙3-CPaR&R_(1)R_(2)混联机构磨损特性分析 被引量:1
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作者 曹毅 刘俊辰 +3 位作者 翟明浩 王保兴 盛永健 居勇健 《哈尔滨工程大学学报》 EI CAS CSCD 北大核心 2021年第6期893-901,共9页
为研究不同物理条件下间隙关节磨损特性,本文以3-CPaR&R_(1)R_(2)混联机构为研究对象并在转动副中考虑间隙的存在,运用Flores接触力模型及修正Coulomb摩擦模型分别建立关节元素间接触点法向接触力及切向接触力模型,关节润滑力则通过... 为研究不同物理条件下间隙关节磨损特性,本文以3-CPaR&R_(1)R_(2)混联机构为研究对象并在转动副中考虑间隙的存在,运用Flores接触力模型及修正Coulomb摩擦模型分别建立关节元素间接触点法向接触力及切向接触力模型,关节润滑力则通过Sommerfeld润滑条件下无限长轴颈-轴承的润滑力模型建立,最终运用拉格朗日方程建立了考虑转动副间隙及关节润滑的动力学数值仿真模型,通过Archard磨损模型分析不同的物理参数对于含间隙关节磨损预测的影响并对比研究有无润滑条件下关节磨损特性。研究结果表明:较高的驱动速度可使间隙磨损相对均匀,但会使磨损深度增加;间隙尺寸对于磨损深度影响较小,但间隙尺寸的增加仍会使磨损深度增加;关节润滑可使间隙关节磨损深度显著减小。 展开更多
关键词 混联机构 关节间隙 动力学 磨损 润滑 flores接触力模型 Coulomb摩擦模型 Sommerfeld润滑条件
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基因工程在花卉业的发展
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作者 赵丽华 杨平 《农业科技通讯》 2008年第7期24-27,共4页
观赏花卉是21世纪的朝阳产业,在很多国家都得以迅猛发展,而成就突出的基因工程技术又为花卉产业的发展提供了全新的思路和手段,本文就基因工程在花卉的花色、花形、花期、保鲜、花香、抗性等方面取得成就进行了综述,并提出目前花卉基因... 观赏花卉是21世纪的朝阳产业,在很多国家都得以迅猛发展,而成就突出的基因工程技术又为花卉产业的发展提供了全新的思路和手段,本文就基因工程在花卉的花色、花形、花期、保鲜、花香、抗性等方面取得成就进行了综述,并提出目前花卉基因工程中存在的问题及展望。 展开更多
关键词 花卉 基因工程 花色 花形 花期 保鲜 花香 抗性
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Analysis of the testimonial evidence of Portugal's first major forensic case:partⅡ 被引量:1
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作者 Ricardo Jorge Dinis-Oliveira 《Forensic Sciences Research》 CSCD 2020年第4期266-285,共20页
The crime possibly perpetrated by a doctor named Vicente Urbino de Freitas in 1890 is one of the most famous cases of poisoning,and it had echoes in the Portuguese and foreign press for several decades.This prestigiou... The crime possibly perpetrated by a doctor named Vicente Urbino de Freitas in 1890 is one of the most famous cases of poisoning,and it had echoes in the Portuguese and foreign press for several decades.This prestigious doctor was convicted of the fatal poisoning of his nephew.He also attempted the homicide of two nieces and their mother-in-law,who only escaped because they obstinately refused to comply with the"therapeutics"prescribed by the family doctor.The motive of the crime should have been Vicente Urbino de Freitas'ambition to receive the family inheritance of his wife,the daughter of the well-known mer-chant Jose Antonio Sampaio of Flores Street in Porto.Vicente Urbino de Freitas was con-victed but doubt about his guilt persists for more than a century.This second work aimed to collect and analyse all the relevant and contradictory testimonial evidence of the prosecu-tion and defence witnesses.This case represents an odd historical record obtained through more than 12years of research on the first major significant Portuguese forensic case.Rare and unprecedented testimonial evidence and photographs were obtained from different countries and then repaired,since these also provide an important historical record of the medical photography. 展开更多
关键词 History of legal medicine forensic sciences forensic toxicology Vicente Urbino de Freitas Mário Guilherme Augusto de Sampaio testimonial evidence flores Street
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Analysis of the autopsy,toxicological,and psychiatric reports of Portugal’s first major forensic case:partⅢ
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作者 Ricardo Jorge Dinis-Oliveira 《Forensic Sciences Research》 CSCD 2021年第4期250-272,共23页
This work presents an odd historical record obtained through more than 14 years of research regarding one of the first major european forensic cases.The presumed homicide of Mário Guilherme Augusto de Sampaio in ... This work presents an odd historical record obtained through more than 14 years of research regarding one of the first major european forensic cases.The presumed homicide of Mário Guilherme Augusto de Sampaio in 1890 was allegedly perpetrated by his uncle,the prestigious doctor vicente Urbino de Freitas.This famous poisoning had international repercussions for decades,with the participation of several forensic experts that made the history of forensic sciences,namely forensic toxicology and pathology.This third work aims to collect,restore,and analyse all the forensic evidence,particularly from the autopsy,toxicological,and psychiatric forensic reports.Facts regarding the life of vicente Urbino de Freitas during his exile in Brazil were also recovered,along with a vast and outstanding assortment of forensic medicine photographs from the 19th century. 展开更多
关键词 Forensic sciences forensic reports ALKALOIDS history of legal medicine flores Street vicente Urbino de Freitas JoséAntónio de Sampaio Junior Mário Guilherme Augusto de Sampaio
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