Finite element analysis of overlay incorporating stress absorbing membrane interlayers against reflective cracking

A wheel tracking test was modelled to gain better understanding of the deflection and stress-strain distribution in an overlaid cracked pavements with and without membrane interlayer （SAMI）. For this purpose, commercial finite element software Abaqus 6.7-1 was used. Two different models were considered, one incorporating stress absorbing membrane interlayers （SAMIs） and the other without SAMI. In the study, full bond condition was assumed for the boundaries between the layers, and a linear elastic model was used for the analysis. The results show that introduction of SAMI caused greater deflection of the pavement. It is found that although with SAMIs, low stiffness is required, a very low stiffness may yield undesirable results. The results show that the introduction of SAMIs results in high strain concentration around the crack region, whilst the strain in the overlay is smaller than the values predicted in the models without SAMIs.     

An experimental study of the effect of low-noise wheels in reducing noise and vibration

Wheel/rail interaction is a major source of railway noise. A low-noise wheel structure is developed and its effect on noise reduction is investigated. This low-noise wheel employs a rubber material inserted into the steel rim or mounted on the wheel surface. The low-noise wheel has low stiffness and a high-damping ratio compared to a solid wheel. Measurement shows that it reduces rolling and squealing. It turns out that a subway line with the proposed wheel could reduce its interior noise level by 4–5 dB(A) and vehicle vibration level by 7–8 dB. While the proposed structure seems promising in noise reduction for railway vehicles, the endurance and cost effectiveness of the low-noise wheel are yet to be verified.     

DETECTION OF HPVB19 IN SERA OF KASHIN-BECK DISEASE PATIENTS

ＴｈｅＰａｒｖｏｖｉｒｉｄａｅａｒｅａｆａｍｉｌｙｏｆｓｍａｌｌＤＮＡｖｉｒｕｓｅｓｗｉｔｈｓｉｎｇｌｅ ｓｔｒａｎｄｅｄ ,ｌｉｎｅａｒｇｅｎｏｍｅｓａｐｐｒｏｘｉ ｍａｔｅｌｙ 5 0 0 0ｎｕｃｌｅｏｔｉｄｅｓ(ｎｔ)ｉｎｌｅｎｇｔｈ .Ｔｈｅｙｉｎｆｅｃｔａｖａｒｉｅｔｙｏｆｈｏｓｔｓ ,ｉｎｃｌｕｄｉｎｇｉｎｖｅｒｔｅｂｒａｔｅｓ ,ｂｉｒｄｓａｎｄｍａｍｍａｌｓ ,ｂｕｔｏｎｌｙｐａｒｖｏｖｉｒｕｓＢ19ｉｓｐａｔｈｏｇｅｎｉｃｔｏｈｕ ｍａｎｂｅｉｎｇ .Ｔｈｅａｇｅｎｔｗａｓｆｉｒｓｔｒｅｃｏｇｎｉｚｅ…     

理解消费者对质量的定义

汽车产品的质量总是会受到巨大的关注。质量较差会导致财务成本的增加,这使得制造商把提升质量作为一项商业必要的手段。过去的数年中有无数方法和流程被用来减少浪费和消除缺陷 (比如6-Sigma法和TQM完全质量管理法)。我们并不缺少这样的衡量工具,来衡量因质量问题和返工而产生的负面经济效益。运用这些衡量工具能够理解质量对每辆车或者公司的盈利能力造成的影响,并且帮助公司取得显著的产品质     

基于条件的近岸风能维修策略综述（英文）

The existing maintenance strategies of offshore wind energy are reviewed including the specific aspects of condition-based maintenance, focusing on three primary phases, namely, condition monitoring, fault diagnosis and prognosis, and maintenance optimization. Relevant academic research and industrial applications are identified and summarized. The state of art, capabilities,and constraints of condition-based maintenance are analyzed. The presented research demonstrates that the intelligent-based approach has become a promising solution for condition recognition, and an integrated data platform for offshore wind farms is significant to optimize the maintenance activities.     

两类锚泊系统在漂浮式双体浮动式波能转换装置垂荡运动状态下的性能（英文）

This work investigated the influence of two types of mooring systems on the hydrodynamic performance of a two-body floating wave energy converter(WEC). It also investigated the effects of the physical parameters of the mooring system on the amount of extractable power from incident waves in the frequency domain. The modeled converter comprised a floating body(a buoy), a submerged body with two mooring systems, and a coupling system for two bodies. The coupling system was a simplified power take-off system that was modeled by a linear spring-damper model. The tension leg mooring system could drastically affect the heave motion of the submerged body of the model and increase relative displacement between the two bodies. The effects of the stiffness parameter of the mooring system on power absorption exceeded those of the pretension tendon force.     

Review of Condition-Based Maintenance Strategies for Offshore Wind Energy

Journal of Marine Science and Application - The existing maintenance strategies of offshore wind energy are reviewed including the specific aspects of condition-based maintenance, focusing on three...     

Research and design of ship-shore integrated engine room intelligent operation and maintenance system based on data brain北大核心CSCD

[目的]为提升舰船机舱运维的智能化水平,针对机舱设备种类多、数量大、耦合关系复杂等特点,梳理机舱运维智能化应用的技术路线,开发船岸一体化机舱智能运维系统。[方法]首先,分析国内外机舱智能运维技术的发展趋势,融合利用健康管理、大数据挖掘、数字孪生、数据轻量化传输等技术优势;然后,设计符合舰船机舱特点的一体化智能运维系统。[结果]提出了一种基于数据大脑赋能的机舱智能运维系统功能框架、平台设计、运行体系、运行流程及关键技术应用。[结论]研究成果可为舰船机舱智能运维系统设计及应用实践提供参考。     

Conflict in the US maritime industry: An account of historical cycles

Historically there have been only two groups involved in the conflict that has engulfed the US maritime industry for the past fifty years maritime labour unions and shipping companies. The configuration of these groups at different times in this struggle, has led to distinct periods of conflict in the industry. This paper analyses the basis and continuation of the problem.     

信号设备状态修的探讨

状态修就是以监测设备和各种检查诊断技术为手段，获取设备运用状态的参数，参照《技规》、《维规》等技术标准，有针对性地对设备运用质量状态临近失效、但尚未故障时进行的预防性的维修。