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241.
计及流体影响的船舶回转冰阻力数值模拟…倪宝玉,黄其,陈绾绶,薛彦卓(1)十字形和X形艉舵航行体的水动力特性对比…陈纪军,潘子英,彭超,夏贤,邱耿耀,李永成(8)波浪增阻计算方法在船型综合优化设计中的应用…孟巧,曲媛,陈玲(17)基于船舶破损安全性的舱室优化方法…边金宁,陈淼,韩涛(23)频选天线罩对阵列天线波束扫描特性影响分析…莫熠,奚秀娟,陈亮,吴为军,王冬冬(31)一种基于有源频率选择表面的可调吸波体特性分析…曾宪亮,张麟兮,万国宾(36)基于CFD的风洞及循环水槽设计系统程序开发…蒋望梁,陈作钢(42)基于视野锥的维修可视性分析方法改进…何春华,方舟,李阳,易朋兴(49)艉部新型球面舱壁结构强度及稳定性分析…侯磊(56)基于改进梯度提升决策树—蒙特卡罗法的超大型集装箱船绑扎桥可靠性分析…李放,王德禹(63)悬挂式铝合金整体壁板压杆的稳定性校核方法…吴剑国,章艺超,张平,陈海涛(70)LNG加注船C型舱优化方案设计…陈兴,叶超,奉宁琛(76)计及日照温差作用的坐坞舰船结构响应分析…李陈峰,王庭策,唐涛,张志超,任慧龙,周学谦(82)舰船加筋板结构的圆孔形穿甲损伤识别方法…吴昊,刘维勤,胡雨晨(88)大尺度高速水下无人艇控制系统设计与试验验证…王文晋,王冠学,李奔,徐国华(95)动力定位船舶全回转推进器工作区优化…尚留宾,王威,刘志华(104)水面无人艇领航—跟随固定时间编队控制…李贺,王宁,薛皓原(111)间歇通信环境下的船舶编队控制…刘睿,于双和,尹广帅(119)基于实时小波变换的燃料电池混合动力船舶能量管理策略…张泽辉,陈辉,高海波,管聪(127)潜艇X舵控制分配器设计和仿真…商建朋,李文魁,黄跃鹏(137)基于有限元法的喷水推进轴系回旋振动分析…马召召,周瑞平,刘琪,范君浩,胡云飞(143)基于小波理论的舰船IMU加速度计信号处理算法…徐博,刘斌,刘德政,崔耀虎,邓伟(151)大洋勘探船岩芯储存库内温度场的数值模拟…郭月姣,吴毅昊,马双,陈旭,孟博,雷淑雅,石大川,冯国增(159)  相似文献   
242.
[1] 航空母舰通道布置对疏散逃生性能的影响…刘伯运,周晓松,闫书逸(1)[2] NACA 0012摆动水翼水动力特性的二维数值模拟…吕元博,田新亮,李欣,宋春辉(7)[3] T型翼控制船舶在波浪上纵向运动的数值研究…孙一方,姜宜辰,宗智(16)[4] 三维有限长圆柱绕流数值模拟…王晓聪,桂洪斌,刘洋(27)[5] 水面舰船集防系统的超压值仿真分析…陈红超,宋靠华,包剑,罗雯军(35)[6] 舱内功能及人机工效导向的载人潜水器工作舱布局设计方法…陈登凯,范昱,张帅,曲俊霖(41)[7] 潜艇破冰上浮近场动力学模型…叶礼裕,王超,郭春雨,常欣(51)[8] 基于空间谐波分析的典型加筋板结构声振特性…高双,朱翔,李天匀,和卫平,魏建辉(60)[9] 管路弯头流致振动的影响因素分析…柯兵(70)[10] 中心典型形状开口的矩形薄板自由振动特性分析…张俊,李天匀,朱翔,郭文杰,陈繁(76)[11] 复合材料舵固有频率优化设计…吴加同,石敏,任春雨(84)[12] 低模高弹体泊松比试验测试方法…周军,梅志远,王永历,周晓松(91)[13] 轮印载荷下多跨梁装载方案聚类分级方法…朱广纪,贺远松,万琪,刘均,程远胜(97)[14] 叶环电驱桨的初步设计及其齿槽转矩的影响因素分析…余平,周军伟,张国政(103)[15] 船用螺旋桨及桨后发电机设计可行性研究…李航,余龙(110)[16] 船用二回路系统全工况热力计算方法及特性分析…崔佳林,杨自春,张磊(116)[17] 基于LS-DYNA的主蒸汽管道防甩设计影响因素分析…薛梅新,杨鹏举,赵翠娜(123)[18] 潜艇推进轴系纵向振动模型与解析研究…徐达,韩保红,赫万恒,于金凤,李维锴(129)[19] 舰船垂向感应磁场精确测量技术…郭成豹,周炜昶(135)[20] 飞行器雷击瞬态电磁响应数值仿真…李茜华,陈曦,刘贺楠,胡志军,彭勇,龙中权,郭俊(140)  相似文献   
243.
文章结合国内外汽车安全技术的发展,选择与设定主动安全、被动安全、耐撞性与维修经济性三方面评价车辆安全性能的具体指标,并基于交通事故环境挖掘了人、时间、地域等影响安全评价的其他因素;利用层次分析法与专家调研法,确定评价车辆安全性能指标的权重,构建出评价车辆安全性能的有效算法,并分析了算法的可行性;基于某大型保险公司201...  相似文献   
244.
Aircraft noise has been regarded as one of the major environmental issues related to air transport. Many airports have introduced a variety of measures to reduce its impact. Several air traffic assignment strategies have been proposed in order to allocate noise more wisely. Even though each decision regarding the assignment of aircraft to routes should consider population exposure to noise, none of the air traffic assignment strategies has addressed daily migrations of population and number of people exposed to noise. The aim of this research is to develop a mathematical model and a heuristic algorithm that could assign aircraft to departure and arrival routes so that number of people exposed to noise is as low as possible, taking into account temporal and spatial variations in population in an airport’s vicinity. The approach was demonstrated on Belgrade airport to show the benefits of the proposed model. Numerical example showed that population exposure to noise could be reduced significantly by applying the proposed air traffic assignment model. As a consequence of the proposed air traffic assignment, overall fuel consumption increased by less than 1%.  相似文献   
245.
Noise pollution in urban areas has many harmful effects on the citizens. There are varieties of noise generation sources of which the traffic noise could be a major source. The point which is perhaps less noticed is that sound level is not the only parameter to indicate the extent and intensity of noise pollution. Situation of urban land uses, distribution of population centers and types of passages can deeply affect the concern on this environmental issue but not with a similar ratio. This article presents an overlaying technique to define noise prone areas using all different factors involved. A case study was carried out in the District 14 of Tehran Metropolitan City where there are busy streets and highways. For this purpose, the share of each criterion in noise pollution intensity was determined using Analytical Hierarchy Process (AHP). Afterwards, the map layers were overlaid based upon the relative importance of the criteria to get the final map on which the noise prone areas are specified. The developed method could be used as a tool for indirect estimation of noise pollution by which instead of direct measurement of the equivalent sound level, it would be possible to predict noise susceptible areas considering the most important influential factors.  相似文献   
246.
Several studies have successfully developed laboratory and field measurement techniques to estimate tyre/road noise damping characteristics. However, laboratory–field noise correlations of pavement types in the form of nomographs is essential to cognize the pavements’ acoustical properties from a practical perspective. A toolkit that readily provides field tyre/road noise intensity of different pavement materials is needed. Thus, the main objective of this study was to develop nomographs with relationships for tyre/road noise versus pavement materials’ viscoelastic–vibroacoustical properties. Isothermal and isochronal nomographs of phase angle–tyre/road noise as toolkits were developed based upon well-established phase angle and noise intensities typical of mixtures, making the nomograph correlations very authentic, realistic, and novel along with benefit to predict tyre/road noise at any desired temperature and traffic speed (or frequency) combination. This study is envisaged to benefit in the discernment of road materials’ damping capabilities from vibroacoustical and field noise–viscoelastic relation aspects.  相似文献   
247.
Many residents are disturbed by road traffic noise which needs to be controlled and managed. The noise map is a helpful and important tool for noise management and acoustical planning in urban areas. However, the static noise map is not sufficient for evaluating noise annoyance at different temporal periods. It is necessary to develop the dynamic noise map or the noise spatiotemporal distribution. In this study, a method about urban road traffic noise spatiotemporal distribution mapping is proposed to obtain the representative road traffic noise maps of different periods. This method relies on the proposed noise spatiotemporal distribution model with two time-dependent variables - traffic density and traffic speed, and the spatiotemporal characteristics derived from multisource data. There are three steps in the method. First, the urban road traffic noise spatiotemporal distribution model is derived from the law of sound propagation. Then, the temporal characteristics are extracted from traffic flow detecting data and E-map road segment speed data by the outlier detection analysis. Finally, the noise distributions corresponding to different periods are calculated by an efficient algorithm which can save 90% above of the computing time. Moreover, a validation experiment was conducted to evaluate the accuracy of the proposed method. There is only 2.26-dB[A] mean absolute error that is within an acceptable range, which shows that the method is effective.  相似文献   
248.
文章针对汽车专业人数多、设备少的教学现状和新时期如何提高教学质量两方面的问题,通过课堂教学实践,利用学习通、微信、手机投屏、希沃手机助手和快手直播等多种手机软件,探索出了汽车专业线上和线下相结合的教学方式。通过此教学改革的应用,基本解决了汽车专业学生设备少、场地不足的问题。由于课堂活动的形式多样,将大部分学生的注意力从网络游戏中拉了回来。在上课过程中同时采用了网络直播的形式,解决了部分学生因病不能正常来校学习的问题,也有利于实现疫情时期的远程教学,从而贯彻“停课不停学”的线下教学模式。  相似文献   
249.
船舶电力系统建模   总被引:10,自引:0,他引:10  
分析研究船舶电力系统的安全性可以运用系统故障仿真手段,但必须对船舶电力系统精确的数学模型进行建模。从某大型集装箱船舶电力系统的工作原理出发,根据柴油发电机组的动态特性,研究了船舶电力系统模型的结构和原理,建立了船舶电力系统模型,该系统可以仿真船舶电力系统的许多运行工况。给出了发电机组正常起动过程和滑油泵、侧推器先后起动时滑油泵电缆发生三相接地故障的仿真过程,对电力系统的参数整定和安全策略的选取有一定的参考价值。  相似文献   
250.
符策  王惠 《中国航海》2004,(1):34-37
为探索软件无线电技术在海上通信中的应用,提出基于软件无线电技术的船舶移动电台的理论结构,并结合船舶通信的特点详细讨论了软件船舶电台的关键技术,展望其发展。  相似文献   
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