Ignition models and simulation of solid propellant of thermodynamic undersea vehicle

The starting characteristics of thermodynamic undersea vehicle systems are determined by the geometry, size and combustion area of solid propellants, which directly effect liquid propellant pipeline design. It is necessary to establish accurate burning models for solid propellants. Based on combustion models using powder rings and two different solid ignition grains, namely star-shaped ignition grains and stuffed ignition grains, a mathematic model of the ignition process of the propulsion system was built. With the help of Matlab, a series of calculations were made to determine the effects of different grains on ignition characteristics. The results show that stuffed ignition grain is best suited to be the ignition grain of a thermodynamic undersea vehicle system.     

工程英语专业机电类专业课双语教学构想

本文从教师、教材和教法方面,探讨了工程英语专业的机电类专业课双语教学的有关问题。旨在提倡构建工程英语专业机电类专业课教学的新模式,主要从双师型队伍建设、教材开发和教学方法改革等方面入手,服务于双语教学,找到英语专业专业课教和学的更好方法。     

便携式船舶智能航迹仪

本文详细介绍了应用ＭＣＳ－８０３２（ＢＡＳＩＣ－５２）单片机ＳＴＤ总线的船舶智能航迹仪的系统的硬件电路和软件设计。该航迹仪具有精度及可靠性高、使用方便、成本极低等特点，可广泛应用于各种船舶。     

西门子车辆测试中心及欧洲地铁车站防灾设施——欧洲地铁考察之三

西门子（SIMENS）车辆测试中心 随着轨道交通系统在大运量交通系统和干线交通系统中越来越广泛的采用．轨道交通技术的发展越来越快．技术更新周期缩短、成本增加。为了适应不断变化的市场．对车辆的开发、制造和测试都提出了新的要求。虽然车辆制造商自己的测试设备都能对以前的车辆进行测试．但并不能迅速适应采用新技术的车辆的测试要求。因此．建立一个适应性广的、综合的、现代化的测试中心是很有必要的。     

对安全气囊应用中存在问题的思考

通过对安全气囊结构的了解，针对其在实际使用中存在的问题，提出关于安全气囊改进措施，使得安全气囊得以充分发挥安全保护性能，在实际应用中得到广泛推广。     

基于CAN总线的舰船发电机节点模块电路板设计

CAN总线是现场总线的一种，它凭借卓越的特性、极高的可靠信与独特的设计，特别适合工业过程监控设备的互联。把CAN总线应用于船舶自动化已经成为控制领域的一种趋势。本文就是探讨如何把CAN总线更好的应用于船舶电站的自动化控制。     

一种基于DSP的宽范围高精度实时数据采集系统的设计

在船用挠性捷联航姿基准系统中，如何保证大动态范围条件下的动调陀螺仪数字量化线路的准确性和实时性是其关键。本文详细介绍了一种基于TMS320VC5409DSP的大动态范围高精度数据采集系统，其动态范围优于140dB，其测量精度满足了航姿基准系统的数据采集要求。     

甲醇锂电池混合动力汽车控制策略分析

文中介绍了一种新型甲醇锂电池混合动力汽车结构及其控制策略。利用排气余热供入甲醇改质器,保证反应所需高温,在气候温度较低时,可提供热量给车载锂电池,保证正常工作温度;按汽车各行驶工况,采用合理控制策略,以保证车辆良好的燃油经济性、动力性和排放性能。     

Non-natural equilibrium contour design for radial tire and its influence on tire performance

Two types of radial tire 11.00R20 and 385/65R22.5 are chosen as the research objects, and their carcass contours are redesigned by using Sakai Hideo’s, Frank’s and the new non-natural equilibrium contour design theories, which were based on analyzing the current non-equilibrium contour design theories of radial tire. Then the tire wear, rolling resistance and grip performance of the two radial tires designed by different non-natural equilibrium contour design theories are comprehensively analyzed with the finite element software ABAQUS. The results show that Frank’s contour design theory can reduce tire wear; the new non-natural equilibrium contour design theory can enhance tire wear, rolling resistance performance, etc. It is also found that the tire carcass contour has great influence on tire performance, especially on the tire rolling resistance. The new non-natural equilibrium contour theory provides a guidance to reduce the tire rolling resistance, and it can break through the target conflicts in tire performance. The tire with the new non-natural equilibrium carcass contour can enhance its comprehensive performance.     

胃癌hPOT1基因单核苷酸多态性与幽门螺杆菌感染的关系

目的探讨胃癌中人端粒保护蛋白1基因(hPOT1)IVS13-98G/T位点单核苷酸多态性与幽门螺杆菌(H.pylori)感染的关系。方法采用聚合酶链反应和限制性片段长度多态性技术(PCR-RFLP)对150例外科手术切除的胃癌患者和156例正常对照者行基因型分析,采用PCR和Warthin-Starry银染色法检测幽门螺杆菌。结果胃癌组hPOT1IVS13-98 T/G位点GG、GT、TT基因型的频率分别22.00%、41.67%、36.67%,G、T等位基因频率分别为42.67%、57.33%;对照组GG、GT、TT基因型的频率分别为24.36%、51.92%、23.72%,G、T等位基因频率分别为49.68%和50.32%。两组G、T等位基因型频率比较无统计学意义(2χ=3.0257,P=0.0820)。以T/T基因型作为参照基因型,G/T和G/G两种基因型OR值分别为0.432(95%CI:0.242-0.772,P=0.005)、0.540(95%CI:0.274-1.064,P=0.075)。胃癌中3种基因型H.pylori的检出率无统计学意义(P>0.05)。结论hPOT1 IVS13-98G/T单核苷酸多态性可能与甘肃胃癌高发区的胃癌患者有关,可能为胃癌的保护因素。胃癌hPOT1 IVS13-98G/T单核苷酸多态性与H.pylori感染无关。