Lights, camera and acoustics: Assessing macrobenthic communities at a dredged material disposal site off the North East coast of the UK

This study presents the results of a trial assessment based on a combination of sampling techniques at a dredged material disposal site located off the North East coast of the UK, over 2001 to 2004. The site was surveyed with a high-resolution sidescan sonar system producing a mosaic with 100% coverage of the survey area. Benthic communities and sediments were ground-truthed using a Hamon grab with a video camera. Additionally, the area was also sampled in 2003 with a Sediment Profile Imaging (SPI) camera, which complemented other techniques by providing in situ information on sediment quality, and biogenic activities. An assessment is made of the benefits of combining the results from conventional methods, principally using grab samples, with those from acoustic techniques and optical imaging devices to determine seafloor and macrobenthic conditions. This information has the potential to contribute to the enhancement of routine monitoring programmes within UK waters.     

Corrosion of working chains continuously immersed in seawater

Chains used in the offshore industry typically are exposed to continued high rates of corrosion, in part due to the working of the chain not permitting a build up of protective rusts. Herein, a procedure is described for estimating the corrosion loss of low-alloy steel chain under continued immersion corrosion conditions. The procedure is based on extensive recent investigations of the effects of water temperature, salinity, water velocity, and surface roughness on steel corrosion under field conditions. Since the working of the chain does not allow corrosion products (rust) to build up on the critical contact surfaces, erosion due to wear and abrasion can be estimated separately. Two example applications are given.     

Design,manufacturing and evaluation of glass/polyester composite crash structures for lightweight vehicles

The development and validation of a modular composite impact structure is presented in the present paper. Quasi-static and dynamic impact tests of the composite components and a full frontal crash test of a vehicle prototype with composite impact structures manufactured by a new UV-pultrusion process have been performed. The results have demonstrated the feasibility of composite impact structures for crash applications with high specific energy absorption values compared with current metallic crash structures. Furthermore, due to the high production capacity of this new manufacturing process, cost-effective composite impact structures for mass-production of conventional cars may be feasible. Finally, a multimaterial numerical model as design tool for crashworthiness applications has also been validated. Different accelerations measured in the crash test have been accurately predicted as well as the crash behaviour of the composite impact structures.     

Ekman transport along the Galician Coast (NW, Spain) calculated from QuikSCAT winds

Ekman transport is studied close to the Galician coast by means of wind data provided by the QuikSCAT satellite from November 1999 to October 2005. Three different coastal zones are identified, western coast from Miño River to Cape Finisterre, middle coast from Cape Finisterre to Cape Ortegal and northern coast, from Cape Ortegal to Cape Peñas. In addition to existence of long-term variations, the periodicity of the transport signal is characterized by an annual component (365 days), a seasonal fluctuation (50–80 days) and a time scale related to passing storms (15–20 days). Although the periodicity of the signal is similar at the three zones due to external meteorological forcing, the Ekman transport is modulated by the presence of the coast, in such a way that seasonal patterns vary in intensity and direction along the coast. Thus, the spring–summer pattern is characterized by high transport at the western coast, pointing seaward perpendicular to the shore-line. The same orientation is observed at the middle coast although with a lower magnitude. Finally, Ekman transport at the northern coast points landward and oblique to the shore-line. The different transport orientations are shown to be responsible for the upwelling probability variation along the coast. On the other hand, the autumn–winter pattern does not show a clear trend with important inter-annual differences showing the high variability of Ekman transport for this period.     

客车制造企业工艺装备的管理

从工装的计划、设计标准化与系列化、资产化、台账信息化和使用与考核等五个方面的管理对多品种、小批量生产模式的客车制造企业的工装管理的关键过程进行分析,指出工装管理应加强计划管理的分解与强化、体系的信息化系统建设.     

Flag state performance: An empirical analysis

Based on data available in mid-2006, the five cooperating international institutions of shipping — BIMCO, Intertanko, Intercargo, ICS, and ISF — produced a summary of factual information on 106 flag states. These international institutions intentionally avoided drawing conclusions on underperformance. This paper extends this assessment allowing for an in-depth empirical assessment of flags performance. Towards this end, the analysis uses weight factors reflecting the importance that an operator might wish to attach on the different variables before making his flag choice, and seeks to statistically (un)group ‘conventionally’ grouped flag states performance. The paper also examines whether IMO membership and/or active participation in the IMO is associated with a greater compliance of a flag-state to safety and relevant environment rules and thus to a better performance. The findings challenge the classic outright categorization of national flags as good performing ones and of commercial flags as those performing badly. The findings also support the suggestion that an active IMO participation, rather than a simple membership, enhances flag performance.     

扬帆江海守望蔚蓝光辉十年回眸危防——中国海事局建局十周年成就之危管防污篇

冬去春来，左搏右击，十年风风雨雨，十年坎坷磨砺，在汹涌澎湃的改革大潮中，中国海事局给海事事业带来了春的希望，夏的热情，秋的收获，冬的和谐。这是一部难忘的历史，这是一段不平的历程，这是一个真实的故事，这是一首雄壮的史诗。危防工作作为海事工作的重要一环，在十年的探索与实践中谱写着属于自己的旋律……     

A generic system dynamics based tool for airport terminal performance analysis

Decision making for airport terminal planning, design and operations is a challenging task, since it should consider significant trade-offs regarding alternative operational policies and physical terminal layout concepts. Existing models and tools for airport terminal analysis and performance assessment are too specific (i.e., models of specific airports) or general simulation platforms that require substantial airport modelling effort. In addition, they are either too detailed (i.e., microscopic) or too aggregate (i.e., macroscopic), affecting, respectively, the flexibility of the model to adapt to any airport and the level of accuracy of the results obtained. Therefore, there is a need for a generic decision support tool that will incorporate sufficient level of detail for assessing airport terminal performance. To bridge this gap, a mesoscopic model for airport terminal performance analysis has been developed, that strikes a balance between flexibility and realistic results, adopting a system dynamics approach. The proposed model has a modular architecture and interface, enabling quick and easy model building and providing the capability of being adaptable to the configuration and operational characteristics of a wide spectrum of airport terminals in a user-friendly manner. The capabilities of the proposed model have been demonstrated through the analysis of the Athens International Airport terminal.     

梅赛德斯-奔驰全新一代E级轿车

更安全 更舒适 更环保 犹如宝马3系之于入门级豪华车，在中大型车这一细分市场．奔驰E级轿车是当之无愧的标杆，无需赘言，超过1200万辆的历史总销量就是最好的佐证。2009年，我们迎来了仿佛从2046年穿越时空回来的全新一代E级轿车，其智能程度之高让人咋舌，通过一系列独特的驾驶辅助功能．提升了安全性。     

Improving noise assessment at intersections by modeling traffic dynamics

Three families of road noise prediction models can be distinguished. Static noise models only consider free-flow constant-speed traffic with uniformly distributed vehicles. Analytic noise models assume that all vehicles are isolated from one another but account for their mean kinematic profile over the network. Micro-simulation noise models relax the hypothesis of no interaction between vehicles and fully capture traffic flow dynamic effects such as queue evolution. This study compares the noise levels obtained by these three methodologies at signalized intersections and roundabouts. It reveals that micro-simulation noise models outperform the other approaches. Particularly, they are able to capture the effects of stochastic transient queues in under-saturated conditions as well as stop-and-go behaviors in oversaturated regime. Accounting for traffic dynamics is also shown to improve predictions of noise variations due to different junction layouts. In this paper, a roundabout is found to induce a 2.5 dB(A) noise reduction compared to a signalized intersection in under-saturated conditions while the acoustic contributions of both kinds of junctions balance in oversaturated regime.