Analysis of Short Sea Shipping-Based Logistics Corridors in the Baltic Sea Region

Despite recent turbulences in global economy, the growth of global trade volumes is expected to continue in the future, leading to increased demands on the performance of logistics networks. The political framework for EU （European Union） Transport Policy Development is presented in the EU White Paper on Transport 2011 in order to build a competitive European transport system. One significant aspect is the promotion of multimodal transport in order to decrease terrestrial transport services （road and rail） and to increase services in the maritime transport sector, especially considering the relief of road and railway infrastructure. Looking at the present situation, SSS （Short Sea Shipping） is already used in many different transport fields all around the world. However, there still exists a great potential which currently is not used or not sufficiently exploited for many different reasons. In order to identify the potential use of SSS in multimodal transport, different scenarios in the Baltic Sea Region and the adjoining hinterland have been developed pointing out alternative solutions for routing. These options are analyzed in detail and evaluated from different perspectives （i.e. transport and handling costs, time consumption and transport-related emissions）. Afterwards, advantages and disadvantages of each alternative will be examined by taking into account economic and ecological aspects in making decision.

Freight Transport Using Short Sea Shipping

The increasing imbalance between road and maritime transport has led to saturation of the terrestrial infrastructures. For this reason, the development and analysis of an intermodal freight transport which is safe, reliable and sustainable is the first step to a more balanced growth of other transport options. In this sense, SSS （Short Sea Shipping） rises like a real and efficient alternative to the land road-based transport as well as integrated to a multimodal system door to door for the freight distribution. This paper aims to evaluate and identify all those parameters required to determine the characteristics ofa SSS service under a theoretical approach. The increasing growth of the transport market demands to the maritime transport an adaptation effort to the redistribution space processes of production centers and consumption and, as a result of it, of the logistic flows and transport. For this reason, a specific methodology has been developed to model all those phases integrated in the logistic chain of SSS. The final purpose is to determine costs and time of each one of them, for its later implementation in a heuristic algorithm of routing analysis. The main driving factors that determine under which conditions the SSS represents an effective and a feasible solution to road freight are also identified. Information regarding European Union programs to promote the SSS is also presented for a better understanding of the ways of funding sustainable freight transport projects. This investigation states an initial basis for evaluating the competitiveness of SSS concepts, and shows where market and environmental circumstances could be handled in order to enhance the competitiveness of SSS.

Assessment of Investment Risk in Greek Short Sea Shipping： A Ro-Ro Passenger Ferry Case

The purpose of this paper is to introduce an innovative methodology in shipping investment evaluation based on simulation of a project cash flow. It concerns a complementary approach to current practices and its aim is to provide more information mainly to ship-owners that consider the feasibility of deploying Ro-Ro Passenger ferries. The paper examines a typical semi-conventional RoPax ferry operating in the Aegean Sea. It addresses important economic, operational and procedural issues concerning risk evaluation. The current status is that risk is a notion still strange to main stakeholders. The Greek practice in performing a feasibility study for a project draws on investor＇s experience and feeling aided by a preliminary economic study. The main thesis of this paper is that there are alternative techniques to evaluate investment risk and measure profitability of a project. A Monte Carlo simulation in collaboration with a typical Ro-Ro cash-flow model is implemented to reveal the extent of risk and provide a useful tool for the assessment of future investments in Greek Short Sea Shipping.

Experimental and Numerical Studies of the Wave-Induced Responses of a River-to-Sea Ship

The ship motions and wave-induced loads of a new type of river-to-sea ship are investigated experimentally and numerically. A river-to-sea ship is an unconventional type of container ship characterized by high breadth to draft ratio and low length to breadth ratio, which makes it more prone to hydroelasticity than conventional ships of the same size. A segmented model was tested under two loading conditions, namely, ballast and loaded conditions, to determine the vertical motions and wave-induced loads under each condition. Results are compared with numerical simulations in the frequency domain. The wave-induced responses are calculated by a nonlinear time domain code at each time step. The response amplitude operators of vertical ship responses in regular waves are analyzed, and the wave-induced responses are consistent with the experimental results.

A synthetic aperture radar sea surface distribution estimation by n-order Bézier curve and its application in ship detection

To dates,most ship detection approaches for single-pol synthetic aperture radar（SAR） imagery try to ensure a constant false-alarm rate（CFAR）.A high performance ship detector relies on two key components：an accurate estimation to a sea surface distribution and a fine designed CFAR algorithm.First,a novel nonparametric sea surface distribution estimation method is developed based on n-order Bézier curve.To estimate the sea surface distribution using n-order Bézier curve,an explicit analytical solution is derived based on a least square optimization,and the optimal selection also is presented to two essential parameters,the order n of Bézier curve and the number m of sample points.Next,to validate the ship detection performance of the estimated sea surface distribution,the estimated sea surface distribution by n-order Bézier curve is combined with a cell averaging CFAR（CA-CFAR）.To eliminate the possible interfering ship targets in background window,an improved automatic censoring method is applied.Comprehensive experiments prove that in terms of sea surface estimation performance,the proposed method is as good as a traditional nonparametric Parzen window kernel method,and in most cases,outperforms two widely used parametric methods,K and G0 models.In terms of computation speed,a major advantage of the proposed estimation method is the time consuming only depended on the number m of sample points while independent of imagery size,which makes it can achieve a significant speed improvement to the Parzen window kernel method,and in some cases,it is even faster than two parametric methods.In terms of ship detection performance,the experiments show that the ship detector which constructed by the proposed sea surface distribution model and the given CA-CFAR algorithm has wide adaptability to different SAR sensors,resolutions and sea surface homogeneities and obtains a leading performance on the test dataset.

The signature analysis of summer Antarctic sea-ice distribution by ship-based sea-ice observation

Based on the Chinese 19th National Antarctic Research Expedition,we carried out ship-based Antarctic sea-ice observa-tion on icebreaker Xue Long using Antarctic sea-ice process and climate (ASPeCt) criteria during austral summer.Sea-ice distribution data were obtained along nearly 6,500 km of the ship’s track.The measurement parameters included sea-ice thickness,sea-ice concentration,snow thickness,and floe size.Analysis showed the presence of the large spatial varia-tions of the observed sea-ice characteristics.Sea-ice concentration varied between 0 and 80 percent and reached its peak value in Weddell Sea because of the specific dynamical process affecting in summer sea-ice melting.There are large areas of open water along the study section.Sea ice and the upper snow thickness of the section varied between 10 cm and 210 cm and 2 cm and 80 cm,respectively,and each reaches its peak values near Amery ice shelf.The floe size varied from less than 10 cm and the maximum of more than 2,000 km along the section.

Interaction between sea ice/iceberg and ship structures: A review

For ship structural design and good maneuverability in an ice-covered sea, the local and global load of ice cover on ships should be well understood. This paper reviews the extensive work done on ice loads on ships, including： （a） Ice pressure and local load determination based on field and model tests; （b） Global ice loads on ships from full-scale field observations, model tests and numerical models under different ice conditions （level ice and pack ice） and ship operations （maneuvering and mooring）. Spe- cial attention is paid to the discrete element simulation of global ice loads on ships; and （c） Analytical solutions and numerical models of impact loads of icebergs on ships for polar navigation. Finally, research potential in these areas is discussed.

大连国际航运中心建设SEA的系统动力学研究

国际航运中心建设是一项复杂的综合性系统工程,系统内存在着错综复杂的关系,可以采用解决非线性问题的系统动力学方法对其进行仿真模拟。针对目前战略环境评价技术方法的不完善,采用系统动力学方法,在分析国际航运中心系统的主要影响因素及其因果关系的基础上,建立了包括人口、经济、交通、能源和环境子系统的系统动力学模型,并利用大连市相关统计数据对模型进行了仿真模拟和验证。通过对仿真结果的分析和预测,符合实际情况,为规划的实施提供科学的决策依据。

基于SEA的沿海高速客船声振预报与控制

利用声仿真软件VA ONE中的统计能量分析(Statistical Energy Analysis,SEA)模块对某沿海高速客船进行全船声振预报及隔振降噪分析。通过声仿真软件建立全船声仿真模型,对主机激励和螺旋桨激励下的船舶做初期声振预报,各主要舱室噪声均不符合规范要求。分析不符要求的舱室噪声产生原因,并且利用软件中的噪声控制模块对相应舱室布置隔声材料,隔声效果明显。软件分析结果可作为研究统计能量分析工程人员的参考。

The application of three-dimensional hydroelastic analysis of ship structures in Pekeris hydro-acoustic waveguide environment

The hydroelastic analysis and sonoelastic analysis methods are incorporated with the Green＇s function of the Pekeris ocean hydro-acoustic waveguide model to produce a three-dimensional sonoelastic analysis method for ships in the ocean hydro-acoustic environment. The seabed condition is represented by a penetrable boundary of prescribed density and sound speed. This method is employed in this paper to predict the vibration and acoustic radiation of a 1 500 t Small Water Area Twin Hull （SWATH） ship in shallow sea acoustic environment. The wet resonant frequencies and radiation sound source levels are predicted and compared with the measured results of the ship in trial.

Seasonal changes in sea ice conditions along the Northeast Passage in 2007 and 2012

Remote sensing data from passive microwave and satellite-based altimeters, associated with the data measured underway, were used to characterize seasonal and spatial changes in sea ice conditions along the Arctic Northeast Passage （NEP） and the high-latitude sea route （HSR） north of the island groups in the eastern Arctic Ocean in 2007 and 2012. In both years, summer Arctic sea ice extent reached minima since satellite records began in 1979. However, there were large differences in spatial distribution of sea ice between the two years. Sea ice conditions in the eastern sections of the sea routes were relatively slight in the 2007 summer, because of the remarkable decline of sea ice in the Pacific sector. A belt of sea ice that blocked sections from the western Laptev Sea to the eastern Kara Sea resulted in both sea routes not completely opening through the 2007 summer. The combination of a great storm in early August causing sea ice to be sheared from the Arctic pack ice and the thick ice surviving the winter delayed the summer opening of the eastern parts of the sea routes in 2012. However, the average open period, defined by 50% ice concentration for the entire NEP and HSR, reached 82 d and 55 d, respectively. Thus, 2012 was the most accessible year since the satellite era began in 1979. The distinct decrease in sea ice in the western parts of the HSR in the 2012 summer can be attributed to the thinning preconditions of sea ice prior to the melt season. The HSR opening can benefit Arctic shipping of deeper-draft vessels.

Ships Bottom Cavities as Shock Absorbers in Waves

Bottom ventilated cavitation is the successfully proven ship drag reduction technology,but the impact of sea waves on ships with bottom cavities is the substantial concern for a broad technology implementation.The influence of waves on vertical force experienced by such ships is analyzed in this paper using a perturbation technique.The unperturbed cavity shape at given Froude number and cavity length was found from a nonlinear steady ideal fluid problem.The ship response to an impact of a wave of the given length and amplitude is considered as the one-frequency perturbation.This perturbation was found by combined consideration of compressible flow in the cavity and incompressible flow in the surrounding water.Computational examples relate to an earlier tested model with the bottom cavity restricted by skegs.The vertical forces on the model with bottom cavities and in cavitation-free conditions were compared in head and following seas.It was found that within the major part of the consider range of wavelengths the cavity acts as a shock absorber significantly reducing the vertical force pulsation and ship acceleration in waves.

江海直达集装箱船线型开发研究

以万吨级江海直达集装箱船为研究对象,针对其船型设计需求,结合计算流体动力学(CFD)方法开展了线型优化,优化线型首部采用低阻的隐形球首形式,尾部采用有利于螺旋桨推进效率的双尾鳍形式,经过优化形成了满足要求的优化线型。基于优化线型进行了快速性模型试验验证,模型试验结果表明,优化线型在设计吃水指定功率下航速可达13.55 kn,高于预期航速,进一步验证了该万吨级江海直达集装箱船线型开发满足设计需求。本文开发的万吨级江海直达集装箱船线型以及优化思路可为后续开展江海直达船线型优化设计提供借鉴与参考。

Application of pre-whitened-constrained-MUSIC in ship-borne radar

In ship-borne radar, because of the influence of interference factors such as the correlation of background array noise and the coherence of targets and so on, the performance of high-resolution algorithms such as MUSIC is degraded. In this document by pre-whitening of background array color noise, de-correlation of coherent targets, compensation of amplitude-phase mismatch, pre-whitened-constrained-MUSIC algorithm in ship-borne radar effectively resolutes ship target and first-order sea echo. Furthermore, the algorithm performance is compared with other algorithms, result shows that pre-whitened-constrained-MUSIC can be applied effectively in high-resolution processing in ship-borne radar.

船舶操纵性海试实验虚拟仿真设计与应用

操纵性试验是船舶海试的重要组成部分,可有效评估船舶投入运营后操纵性能的优劣。船舶操纵性海试准备时间长、成本高、风险大,难以开展实验教学。依托虚拟仿真软硬件设施,充分融合虚拟现实技术、3D成像投影技术与船舶操纵性能分析方法,探索新型实验教学模式,完成船舶操纵性海试虚拟仿真设计;并以集装箱船为例,开展实验教学应用研究。船舶操纵性海试实验虚拟仿真有效弥补了海试的诸多不足,为学生沉浸式体验船舶操纵性海试全过程、掌握相关实验规程与分析方法提供良好的虚拟仿真环境。

前沿科研成果融入船舶快速性课程教学探索

随着科学技术的不断发展,科研成果的产出使得传统教学形式和教学内容产生重要变革。该文结合新型船舶及新型推进方式,将前沿科学技术进步趋势和研究成果融入船舶快速性课程教学,立足于海洋强国战略需求,紧跟船舶海洋领域前沿科研发展形势,不断充实和完善船舶快速性教学内容,从而使教学内容适应船舶行业快速发展的变化形式,将最新科研成果融入教学,丰富教学内容,开拓学生视野,培养学生对船舶海洋领域国际前沿问题的敏感性和前瞻性。

基于海上观测值的舰船导航信号滤波方法研究

为弥补单一数据源不足,并在不同航行环境下,确保导航信号的稳定性与可靠性,研究基于海上观测值的舰船导航信号滤波方法。在舰船导航中,基于纬度、经度、海流分量、航速、航向和角速度变化量等观测值建立了导航信号模型。利用改进量子粒子群优化算法,优化卡尔曼滤波算法的观测噪声协方差矩阵,以及舰船导航信号模型噪声协方差矩阵,得到改进卡尔曼滤波算法,结合舰船导航信号模型,获取舰船导航信号滤波估计结果。实验结果证明,该方法可有效滤波估计舰船导航信号,提升舰船导航信号质量;该方法改进后的舰船导航轨迹与期望轨迹非常接近,即改进后该方法的舰船导航信号滤波效果较优。

两栖攻击舰编队海上航渡对潜防御队形优化配置研究

针对两栖攻击舰编队对潜防御时的队形配置问题,从潜艇对编队的威胁分析入手,建立了潜艇鱼雷极限射距圆模型,通过模型分析与仿真计算,得出了两栖攻击舰应配置在威胁圆圆心稍后位置的结论,并给出了优化位置计算模型;结合潜艇威胁范围与威胁距离模型及警戒舰艇对潜防御范围模型,给出了护航兵力优化配置方法,为两栖攻击舰编队海上航渡时的对潜防御提供了参考。

DDPG深度强化学习算法在无人船目标追踪与救援中的应用

为保证海上救援活动的高效性,研究结合深度确定性策略梯度算法(Deep Deterministic Policy Gradient,DDPG)从状态空间、动作空间、奖励函数方面对船只追踪救援目标算法进行设计,并实际应用到无人船追踪救援之中。结果显示DDPG算法的稳定成功率接近100%,性能优异。该设计的算法最终回合累积奖励值能够稳定在10左右,而平均时长则能稳定在80 s左右,能够根据周边环境的状态调整自己的运动策略,满足海上救援活动中的紧迫性要求,能为相关领域的研究提供一条新的思路。

论北方海航道开发前景:气候、海运与破冰船

随着全球气候不断变暖,北极冰川融化加剧,北方海航道海域冰层日趋缩小和变薄,为北方海航道开发提供了历史性机遇。全球化趋势下,国际货物贸易飞速发展,国际海运尤其是欧亚大陆间海运活动昌盛,传统南方航道面临压力,为北方海航道开发提供了现实需求。破冰船自出现以来,不断迭代升级,在动力、船体设计、船体材料、辅助设备等方面飞速发展,破冰能力不断提高,为北方海航道开发提供了技术可能。近年来北方海航道的开发取得飞速发展,而且俄罗斯仍在加大对北方海航道的开发力度,但北方海航道开发也面临国际合作环境恶化、资金投入大、经济性不强等问题。整体而言,在气候变暖、海运需求旺盛和破冰船技术不断发展的大背景下,长期来看,北方海航道开发的前景仍十分广阔。