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A coupled convolutional neural network for small and densely clustered ship detection in SAR images
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作者 Juanping ZHAO Weiwei GUO +1 位作者 Zenghui ZHANG Wenxian YU 《中国科学:信息科学(英文版)》 SCIE EI CSCD 2019年第4期107-122,共16页
Ship detection from synthetic aperture radar(SAR) imagery plays a significant role in global marine surveillance. However, a desirable performance is rarely achieved when detecting small and densely clustered ship tar... Ship detection from synthetic aperture radar(SAR) imagery plays a significant role in global marine surveillance. However, a desirable performance is rarely achieved when detecting small and densely clustered ship targets, and this problem is difficult to solve. Recently, convolutional neural networks(CNNs)have shown strong detection power in computer vision and are flexible in complex background conditions,whereas traditional methods have limited ability. However, CNNs struggle to detect small targets and densely clustered ones that exist widely in many SAR images. To address this problem while preserving the good properties for complex background conditions, we develop a coupled CNN for small and densely clustered SAR ship detection. The proposed method mainly consists of two subnetworks: an exhaustive ship proposal network(ESPN) for ship-like region generation from multiple layers with multiple receptive fields, and an accurate ship discrimination network(ASDN) for false alarm elimination by referring to the context information of each proposal generated by ESPN. The motivation in ESPN is to generate as many ship proposals as possible, and in ASDN, the goal is to obtain the final results accurately. Experiments are evaluated on two data sets. One is collected from 60 wide-swath Sentinel-1 images and the other is from20 GaoF en-3(GF-3) images. Both data sets contain many ships that are small and densely clustered. The quantitative comparison results illustrate the clear improvements of the new method in terms of average precision(AP) and F 1 score by 0.4028 and 0.3045 for the Sentinel-1 data set compared with the multi-step constant false alarm rate(CFAR-MS) method. The values are verified as 0.2033 and 0.1522 for the GF-3 data set. In addition, the new method is demonstrated to be more efficient than CFAR-MS. 展开更多
关键词 SAR image SHIP detection CNN EXHAUSTIVE SHIP proposal network(ESPN) accurate SHIP DISCRIMINATION network(ASDN)
Enhancing the observing capacity for the surface ocean by the use of Volunteer Observing Ship 预览
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作者 Zong-Pei Jiang Jiajun Yuan +1 位作者 Susan E.Hartman Wei Fan 《海洋学报:英文版》 SCIE CAS CSCD 2019年第7期114-120,共7页
Knowledge of the surface ocean dynamics and the underlying controlling mechanisms is critical to understand the natural variability of the ocean and to predict its future response to climate change.In this paper,we hi... Knowledge of the surface ocean dynamics and the underlying controlling mechanisms is critical to understand the natural variability of the ocean and to predict its future response to climate change.In this paper,we highlight the potential use of Volunteer Observing Ship(VOS),as carrier for automatic underway measuring system and as platform for sample collection,to enhance the observing capacity for the surface ocean.We review the concept,history,present status and future development of the VOS-based in situ surface ocean observation.The successes of various VOS projects demonstrate that,along with the rapid advancing sensor techniques,VOS is able to improve the temporal resolution and spatial coverage of the surface ocean observation in a highly cost-effective manner.A sustained and efficient marine monitoring system in the future should integrate the advantages of various observing platforms including VOS. 展开更多
关键词 VOLUNTEER observing SHIP SHIP of OPPORTUNITY SURFACE OCEAN in SITU observation sensor
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基于SEEMP的船舶营运能效评价指数的开发及应用:韩国某案例研究 预览
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作者 Nam-kyun IM Bora Choe Chung-Hwan Park 《船舶与海洋工程学报:英文版》 CSCD 2019年第2期185-194,共10页
The CO2 emission reduction policy of the International Maritime Organization(IMO)recommends that the operation of ships,managed by maritime transport companies,should be energy-efficient.An evaluation method that can ... The CO2 emission reduction policy of the International Maritime Organization(IMO)recommends that the operation of ships,managed by maritime transport companies,should be energy-efficient.An evaluation method that can determine how successfully a ship implements the energy efficiency plan is proposed in this study.To develop this method,the measures required for energy-efficient ship operations according to the Ship Energy Efficiency Management Plan(SEEMP)operational guidelines were selected.The weights of the selected measures,which indicate how they contribute to the energy-efficient operation of a ship,were derived using a survey based on the analytic hierarchy process(AHP)method.Consequently,using these measures and their weights,a new evaluation method was proposed.This evaluation method was applied to shipping companies in South Korea,and their ship operation energy efficiency indices were derived and compared.This evaluation method will be useful to the government and shipping companies in assessing the energy efficiency of ship operations. 展开更多
关键词 SHIP GREENHOUSE gas SHIP ENERGY EFFICIENCY Management Plan ENERGY EFFICIENCY Operational Indicator ENERGY EFFICIENCY Design Index
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基于耦合作用的建筑泥浆运输船适货性评价模型 预览
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作者 薛孝行 吴建军 胡甚平 《中国航海》 CSCD 北大核心 2019年第2期83-86,共4页
为研究装载建筑泥浆的船舶的安全性能,通过分析建筑泥浆的特性与其专用运输船的结构特点和性能,研究货-船间的耦合效应,阐述耦合效应与船舶安全之间的关系,建立建筑泥浆运输船层次评价体系,利用模糊层次分析法(Fuzzy Analytic Hierarchy... 为研究装载建筑泥浆的船舶的安全性能,通过分析建筑泥浆的特性与其专用运输船的结构特点和性能,研究货-船间的耦合效应,阐述耦合效应与船舶安全之间的关系,建立建筑泥浆运输船层次评价体系,利用模糊层次分析法(Fuzzy Analytic Hierarchy Process,FAHP),构建建筑泥浆运输船评价模型,获得该类型船舶的评价结果。通过算例进行验证,计算结果表明:该技术方法和评价模型可用于建筑泥浆运输船适货性安全评价工作中,对推动船舶的适货性研究具有一定意义。 展开更多
关键词 船舶 船舶适货性 泥浆运输 模糊层次分析法
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An investigation on HOBEM in evaluating ship wave of high speed displacement ship 预览
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作者 Xi Chen Ren-chuan Zhu +1 位作者 Ya-lan Song Ju Fan 《水动力学研究与进展:英文版》 SCIE EI CSCD 2019年第3期531-541,共11页
A practical numerical tool is developed to evaluate ship waves of high speed displacement ships on the basis of potential flow theory, in which high order boundary element method (HOBEM) based on biquadratic shape fun... A practical numerical tool is developed to evaluate ship waves of high speed displacement ships on the basis of potential flow theory, in which high order boundary element method (HOBEM) based on biquadratic shape functions is applied to solve the boundary value problem. Since the sinkage and trim of ship at high speeds are notable, influences of ship attitude on wave drag are investigated and three kinds of models are used to evaluate them. To make the numerical approach highly efficient, an incomplete LU factorization preconditioner is adopted and incorporated with the restarted generalized minimal residual method GMRES (m) to solve the boundary integral equation. A corresponding Fortran code is developed and applied to evaluate ship waves of the Wigley hull and 4a model, a transom stem ship. Computations are performed for both monohulls and catamarans over a wide range of Froude numbers (Fr= 0.10-l.00). Numerical issues including mesh convergence and computational efficiency are investigated at first. Computed results of the wave drag, sinkage and trim show generally good agreement with experimental data. Reasonable wave patterns are obtained and physical phenomena that wake angle max, where the largest waves occur, would become narrow at high speeds is also captured by the present computations. Numerical results indicate the proposed method would be accurate and efficient to evaluate resistance for hull design of high speed displacement ship. 展开更多
关键词 High speed SHIP SHIP WAVES HOBEM ILU-GMRES SINKAGE and TRIM
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乳康饮对裸鼠乳腺癌组织PI3K/Akt信号通路相关因子表达的影响
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作者 李湘奇 王莹 +2 位作者 魏昌然 刘晓菲 李静蔚 《中华中医药学刊》 CAS 北大核心 2019年第7期1543-1547,共5页
目的:观察中药乳康饮对移植瘤小鼠乳腺癌PI3K/AKT信号通路相关因子表达的影响,探讨其抑制乳腺癌的作用机制。方法:60只BALB/c裸鼠乳腺原位种植人乳腺癌细胞株MDA-MB-231,建立乳腺癌移植瘤自发性转移模型,随机分成6组,分别为模型对照组,5... 目的:观察中药乳康饮对移植瘤小鼠乳腺癌PI3K/AKT信号通路相关因子表达的影响,探讨其抑制乳腺癌的作用机制。方法:60只BALB/c裸鼠乳腺原位种植人乳腺癌细胞株MDA-MB-231,建立乳腺癌移植瘤自发性转移模型,随机分成6组,分别为模型对照组,5-FU对照组、疏肝理气组、化痰散瘀组、益气健脾组、乳康饮组,每组10只。分别给予生理盐水、5-FU、乳康饮及各拆方(疏肝理气、化痰散瘀、益气健脾)药物灌胃,灌胃液体量均为0.4 mL/(d·只),均1次/d,连续6周后将裸鼠处死,检测裸鼠第2、3对乳腺原位肿瘤PI3K、Akt、PTEN、SHIP蛋白水平及mRNA的表达。结果:乳康饮及各拆方组药物对PI3K、Akt mRNA的表达均起到抑制作用,对PTEN、SHIP mRNA表达有促进作用,与模型对照组比较差异有统计学意义(均P<0.05或P<0.01),而益气健脾组和乳康饮全方效果更具优势;裸鼠乳腺癌组织PI3K、Akt、PTEN、SHIP蛋白水平的表达的检测结果,乳康饮组及各拆方组对PI3K、Akt蛋白的表达均有不同程度的抑制作用,对抑癌因子PTEN、SHIP蛋白的表达有促进作用,各拆方组之间也存在统计学差异,乳康饮的作用明显优于各拆方组(P<0.05或0.01)。结论:乳康饮可能通过抑制PI3K、Akt的表达,促进PTEN、SHIP的表达,调控PI3K/AKT信号通路,对乳腺癌的发生发展起到抑制作用。 展开更多
关键词 乳腺癌 乳康饮 磷脂酰肌醇3-激酶/丝苏氨酸蛋白激酶B信号通路 PTEN SHIP
乍浦港区船舶急涨流进港船首右偏致失控的风险 预览
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作者 徐晓 《广州航海学院学报》 2019年第3期26-29,共4页
本文运用船舶水动力学原理,根据乍浦港区流场水平和垂向不均匀性分布特征,结合进港航路方向水深连续变浅和当地盛行风况实际,说明了船舶急涨流进港船首右偏效应的主要成因和影响因素;分析了不当操纵措施引发的船舶急涨流进港船首右偏致... 本文运用船舶水动力学原理,根据乍浦港区流场水平和垂向不均匀性分布特征,结合进港航路方向水深连续变浅和当地盛行风况实际,说明了船舶急涨流进港船首右偏效应的主要成因和影响因素;分析了不当操纵措施引发的船舶急涨流进港船首右偏致失控的风险,并提出了合理的防范和应急处置措施. 展开更多
关键词 船舶 偏转 流场 分布
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Fuzzy Optimal Control Design for Ship Steering 预览
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作者 EJAZ Muhammad CHEN Mou 《南京航空航天大学学报:英文版》 EI CSCD 2019年第3期459-467,共9页
This paper presents a method to design a control scheme for nonlinear systems using fuzzy optimal control.In the design process,the nonlinear system is first converted into local subsystems using sector non linearity ... This paper presents a method to design a control scheme for nonlinear systems using fuzzy optimal control.In the design process,the nonlinear system is first converted into local subsystems using sector non linearity approach of Takagi Sugeno(T S)fuzzy modeling.For each local subsystem,an optimal control is designed.Then,the parameters of local controllers are defuzzified to construct a global optimal controller.To prove the effectiveness of this control scheme,simulations are performed using the mathematical model of Esso Osaka tanker ship for set point regulation with and without disturbance and reference tracking.In addition,the simulation results are compared with that of a PID controller for further verification and validation.It has been shown that the proposed optimal controller can be used for the nonlinear ship steering with good rise time,zero steady state error and fast settling time. 展开更多
关键词 Takagi Sugeno(T S) fuzzy modeling OPTIMAL control OPTIMAL linear QUADRATIC TRACKER (LQT) SHIP STEERING
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船舶海上航行路径三维虚拟系统设计 预览
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作者 王文震 《舰船科学技术》 北大核心 2019年第6期58-60,共3页
传统的船舶海上航行路径三维虚拟系统存在着虚拟清晰度低的缺陷,为此提出船舶海上航行路径三维虚拟系统设计。船舶海上航行路径三维虚拟系统硬件设计包括船舶海上航行路径数据信息采集单元、三维虚拟设备单元与通信单元,软件设计包括三... 传统的船舶海上航行路径三维虚拟系统存在着虚拟清晰度低的缺陷,为此提出船舶海上航行路径三维虚拟系统设计。船舶海上航行路径三维虚拟系统硬件设计包括船舶海上航行路径数据信息采集单元、三维虚拟设备单元与通信单元,软件设计包括三维虚拟场景设计、船舶海上航行路径数据信息库设计与船舶海上航行路径三维虚拟设计,通过硬件与软件设计实现了船舶海上航行路径三维虚拟系统的运行。通过实验得到,设计的船舶海上航行路径三维虚拟系统虚拟清晰度比传统系统高出28%,说明设计的船舶海上航行路径三维虚拟系统虚拟效果更好。 展开更多
关键词 船舶 海上 航行路径 三维 虚拟
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含NaCl低压细水雾抑制受限空间油池火研究 预览
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作者 霍东晨 徐伟程 +3 位作者 肖林 白雪 郭晨宇 王亮 《消防科学与技术》 CAS 北大核心 2019年第5期647-649,共3页
针对高压细水雾灭火系统在抑制船舶油料火灾过程中的强化燃烧及设备布置空间大等缺点,利用1.5 m×1.5 m×1.0m封闭舱室平台,以正庚烷为燃料,实验研究不同NaCl质量分数(5%、10%、15%、20%)添加剂的低压细水雾(0.2~0.6 MPa)抑制... 针对高压细水雾灭火系统在抑制船舶油料火灾过程中的强化燃烧及设备布置空间大等缺点,利用1.5 m×1.5 m×1.0m封闭舱室平台,以正庚烷为燃料,实验研究不同NaCl质量分数(5%、10%、15%、20%)添加剂的低压细水雾(0.2~0.6 MPa)抑制油池火特性。分析了细水雾灭火过程中的燃烧状态、火焰温度和灭火时间。结果表明:在压力为0.4、0.6 MPa下的细水雾,灭火时间随着NaCl质量分数的提升大致呈"V"型规律;在相同的NaCl质量分数下,压力越高,灭火效果越好,时间最短为35 s。 展开更多
关键词 船舶 受限空间 NaCl添加剂 低压细水雾 油池火
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船舶水上纵向运动的非线性数学模型构建 预览
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作者 关砚蓬 《舰船科学技术》 北大核心 2019年第4期1-3,共3页
为了解决当前船舶水上纵向运动预测精度的问题,设计了一种船舶水上纵向运动的非线性数学模型构建方法。首先分析了当前船舶水上纵向运动的线性数学模型的缺陷,然后引入非线性建模方法—神经网络对船舶水上纵向运动变化特点进行拟合,建... 为了解决当前船舶水上纵向运动预测精度的问题,设计了一种船舶水上纵向运动的非线性数学模型构建方法。首先分析了当前船舶水上纵向运动的线性数学模型的缺陷,然后引入非线性建模方法—神经网络对船舶水上纵向运动变化特点进行拟合,建立船舶水上纵向运动的非线性预测模型,最后与线性船舶水上纵向运动建模方法进行仿真对比实验。结果表明,本文方法的船舶水上纵向运动预测精度高,船舶水上纵向运动预测误差要小于线性船舶水上纵向运动建模方法,验证了本文非线性船舶水上纵向运动建模方法的有效性以及优越性。 展开更多
关键词 船舶 水上纵向运动 非线性数学模型 改进神经网络
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混流式喷水推进泵导叶的反问题设计及数值验证 预览
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作者 王声森 苏石川 +1 位作者 冯德胜 曹佳斌 《机电设备》 2019年第2期8-13,共6页
采用反问题设计方法,在满足设计流量、转速、扬程、推力等参数的条件下对原始导叶进行重新设计,以提高喷水推进泵导叶性能。通过调整叶片载荷分布,构造了前、中、后3种加载形式,获得了相应的导叶形状。使用计算流体动力学方法,在额定工... 采用反问题设计方法,在满足设计流量、转速、扬程、推力等参数的条件下对原始导叶进行重新设计,以提高喷水推进泵导叶性能。通过调整叶片载荷分布,构造了前、中、后3种加载形式,获得了相应的导叶形状。使用计算流体动力学方法,在额定工况下对所得导叶进行数值模拟,选择最优结果并在多工况下进行数值计算并验证推力。计算结果表明:前载型导叶流道较短,可有效抑制角区分离,额定工况下导叶效率达到94.95%,喷泵效率较后载型提升2.14%,扬程高出设计参数3.24m,变工况条件下推力均高出设计要求。计算结果验证了反问题设计方法的可行性及有效性。 展开更多
关键词 船舶 喷水推进泵 导叶 反问题设计 载荷分布 数值验证
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VR技术在船舶消防培训中的应用 预览
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作者 朱苏 周卫平 +1 位作者 李酬 陈极 《造船技术》 2019年第4期89-92,共4页
为了加强船舶高级消防技能专业化训练,基于当前船舶消防培训的现状,提出基于VR技术的船舶消防模拟实训模式。结合工程应用,详细介绍基于VR技术的消防基础知识实训、船舶结构认知实训、船舶高级消防分布式仿真实训等系统的功能和特点。... 为了加强船舶高级消防技能专业化训练,基于当前船舶消防培训的现状,提出基于VR技术的船舶消防模拟实训模式。结合工程应用,详细介绍基于VR技术的消防基础知识实训、船舶结构认知实训、船舶高级消防分布式仿真实训等系统的功能和特点。系统已得到初步应用,可为船舶高级消防培训提供一种新思路。 展开更多
关键词 VR 船舶 消防 培训
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Structural Optimization of Dust Removal Tank of Ship Desulphurization Equipment 预览
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作者 Han Mingyang Gou Shenlong +3 位作者 Zheng Wei Zhang Chao Deng Xin Zhou Junbo 《气象与环境研究:英文版》 CAS 2019年第4期88-92,共5页
With the improvement of the international community s environmental requirements, ship emissions standards are more stringent. In order to complete the exhaust gas purification work, Dafa 6DL-26 diesel engine set is u... With the improvement of the international community s environmental requirements, ship emissions standards are more stringent. In order to complete the exhaust gas purification work, Dafa 6DL-26 diesel engine set is used for simulation. Finite element multi-phase flow model and DPM model are used for numerical simulation and structural optimization of the position of dust removal tank at the desulfurization pretreatment part (Venturi segment). The results show that it can effectively optimize the flow field and reduce the power consumption of the marine diesel engine when the rightmost axis of the dust removal tank coincides with the axis of the Venturi center. 展开更多
关键词 SHIP EXHAUST gas DUST REMOVAL TANK Structural optimization
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艇体及对接装置的仿真数学模型研究 预览
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作者 黄长琴 《舰船科学技术》 北大核心 2019年第6期16-18,共3页
提出一种用于艇体水下对接的仿真数学模型,分析了水下潜艇与艇体对接装置受到的水流阻力与深水压力,并确定出机械臂旋转的自由度与空间运动距离;构建出数学模型与对接装置的运动方程,求解对接装置中心坐标的空间运动矩阵,与机械臂运动... 提出一种用于艇体水下对接的仿真数学模型,分析了水下潜艇与艇体对接装置受到的水流阻力与深水压力,并确定出机械臂旋转的自由度与空间运动距离;构建出数学模型与对接装置的运动方程,求解对接装置中心坐标的空间运动矩阵,与机械臂运动的最优路径,实现水下对接装置与艇体的精确对接。仿真结果表明:本文提出的数学控制模型所确定的机械臂运动角度、距离与理论值重叠度很高,控制误差相对于传统水下对接装置优势明显。 展开更多
关键词 舰艇 对接装置 数学模型 最优路径
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船舶参数横摇非线性力学特征数值分析 预览
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作者 杨波 王骁 吴明 《船舶力学》 EI CSCD 北大核心 2019年第7期802-809,共8页
为研究船舶参数横摇发生的力学机理,文章基于计算流体力学方法,对DTMB5512船模规则波顶浪航行时的参数横摇运动进行了数值模拟。模拟结果表明:参数横摇复原力矩曲线会随横摇角增大而出现2个拐点,呈现出先增大、后减小、再增大的非线性特... 为研究船舶参数横摇发生的力学机理,文章基于计算流体力学方法,对DTMB5512船模规则波顶浪航行时的参数横摇运动进行了数值模拟。模拟结果表明:参数横摇复原力矩曲线会随横摇角增大而出现2个拐点,呈现出先增大、后减小、再增大的非线性特征;其零点、拐点及最大值点可以分别用垂荡、纵摇及船/波相对位置进行表征。文中方法实现了船舶参数横摇力学特征的数值分析,可为船舶波浪中的完整稳性评估提供新的方法。 展开更多
关键词 船舶 参数横摇 非线性特征 计算流体力学
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与船舶专业知识相结合的单片机实验教学改革研究 预览
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作者 方智 方春慧 《科技创新导报》 2019年第16期217-218,220共3页
为解决现有的单片机教学模式中理论与实践相脱节的教学弊端,提出一种仿真和实验板相结合的双平台单片机教学改革方案。主要采用“理论教学+Keil编译软件+Proteus仿真软件”和“实践教学+Keil编译软件+实验板”的虚实结合的双平台教学思... 为解决现有的单片机教学模式中理论与实践相脱节的教学弊端,提出一种仿真和实验板相结合的双平台单片机教学改革方案。主要采用“理论教学+Keil编译软件+Proteus仿真软件”和“实践教学+Keil编译软件+实验板”的虚实结合的双平台教学思路,将理论教学和Proteus仿真平台以及开发板实践平台相融合,兼顾虚实双平台的优势,结合船舶专业开设相关实验使用单片机控制船模,激发学生学习理论知识和自主实践的兴趣,进而达到培养学生的科研素质和工程实践能力,提高学生创新意识的目的。 展开更多
关键词 双平台 单片机 船舶 教学改革
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Effects of C-terminal amidation and heptapeptide ring on the biological activities and advanced structure of amurin-9KY,a novel antimicrobial peptide identified from the brown frog,Rana kunyuensis
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作者 Fen Zhang Zhi-Lai Guo +3 位作者 Yan Chen Li Li Hai-Ning Yu Yi-Peng Wang 《动物学研究》 CAS CSCD 2019年第3期198-204,共7页
Rana kunyuensis is a species of brown frog that lives exclusively on Kunyu Mountain,Yantai,China.In the current study,a 279-bp cDNA sequence encoding a novel antimicrobial peptide (AMP),designated as amurin-9KY,was cl... Rana kunyuensis is a species of brown frog that lives exclusively on Kunyu Mountain,Yantai,China.In the current study,a 279-bp cDNA sequence encoding a novel antimicrobial peptide (AMP),designated as amurin-9KY,was cloned from synthesized double-strand skin cDNA of R.kunyuensis.The amurin-9KY precursor was composed of 62 amino acid (aa) residues,whereas the mature peptide was composed of 14 aa and contained two cysteines forming a C-terminal heptapeptide ring (Rana box domain) and an amidated C-terminus.These structural characters represent a novel amphibian AMP family.Although amurin-9KY exhibited high similarity to the already identified amurin-9AM from R.amurensis,little is known about the structures and activities of amurin-9 family AMPs so far.Therefore,amurin-9KY and its three derivatives (amurin-9KY1-3) were designed and synthesized.The structures and activities were examined to evaluate the influence of C-terminal amidation and the heptapeptide ring on the activities and structure of amurin-9KY..Results indicated that C-terminal amidation was essential for antimicrobial activity,whereas both C-terminal amidation and the heptapeptide ring played roles in the low hemolytic activity.Circular dichroism (CD) spectra showed that the four peptides adopted an α-helical conformation in THF/H2O (v/v 1∶1) solution,but a random coil in aqueous solution.Elimination of the C-terminal heptapeptide ring generated two free cysteine residues with unpaired thiol groups,which greatly increased the concentration-dependent anti-oxidant activity.Scanning electron microscopy (SEM) was also performed to determine the possible bactericidal mechanisms. 展开更多
关键词 Antimicrobial peptides RANA kunyuensis' Amurin-9KY Heptapeptide RING C-TERMINAL AMIDATION STRUCTURE activity relati on ship
船舶溢油事故态势演化风险排序 预览
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作者 王海燕 陈洁 《中国航海》 CSCD 北大核心 2019年第3期89-94,共6页
为降低溢油事故对近岸水域造成的影响,采用科学方法识别溢油事故发生后系统可能存在的各种风险和演化态势,并通过风险排序找出船舶溢油事故应急处置的重点。分析船舶溢油事故发生后人、机、环境、管理系统中影响溢油事故态势发展的关键... 为降低溢油事故对近岸水域造成的影响,采用科学方法识别溢油事故发生后系统可能存在的各种风险和演化态势,并通过风险排序找出船舶溢油事故应急处置的重点。分析船舶溢油事故发生后人、机、环境、管理系统中影响溢油事故态势发展的关键因素,识别其中可能存在的风险。采用改进的(Technique for Order Preference by Similarity to an Ideal Solution,TOPSIS)法,考虑风险指标的模糊性和不确定性,将模糊集与TOPSIS法相结合,建立船舶溢油事故态势演化风险排序模型。实例验证排序模型的实用性,为提高溢油应急处置效率,降低溢油事故后果提供理论依据。 展开更多
关键词 TOPSIS 船舶 溢油 态势演化 风险排序
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With Belt and Road Vitality, Export to Main tain Growth Momentum
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作者 《船舶经济贸易》 2019年第4期68-70,共3页
China ship export achieved good performance in 2018 as a result of great efforts of the national shipbuilding industry with strong support of various national policies and nirasures of stabilize foreign trade. China s... China ship export achieved good performance in 2018 as a result of great efforts of the national shipbuilding industry with strong support of various national policies and nirasures of stabilize foreign trade. China ship export totaled US$25.036 billion in 2018. a vear-onyear growth of 10.2%. 展开更多
关键词 China ship EXPORT RESULT of GREAT EFFORTS foreign trade
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