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31.
In this paper, we present a Finite pointset method (FPM) for the numerical simulation of free surface flow around a ship in calm water. It is a Lagrangian and meshless particle scheme which is applied to the projection method for the incompressible governing equations. This requires the solution of Poisson problems in each time step, so a moving least squares (MLS) interpolants is used for the spatial derivatives in order to discretize the Poisson equation with pressure-Dirichlet condition of free surface flow in meshless structure. Meanwhile, an additional problem of the periodic particle locations redistribution in the present approach is still handled by MLS interpolants. With the proposed FPM technique, problems associated with the free surface flow around a ship are circumvented. A verification of numerical modeling is made using the Wigley hull and the validity of the proposed methodology is examined by comparing the detail of wave profile and wave-making resistance with Series 60 model. The results demonstrate that FPM is able to perform efficient and stable simulations of free surface flow around a ship. 相似文献
32.
After several years of negotiation between Canada and the European Union, the Comprehensive and Economic Trade Agreement (CETA) was ratified in early 2017. The regime set out by the Canadian Coasting Trade Act that reserves shipments of cargo between Canadian ports to Canadian vessels remains mostly untouched under CETA. Minor, yet potentially significant, changes to the regime are introduced by the trade agreement. Provisions are made to liberalize the repositioning of empty containers within Canada. The liberalization of public markets now allows European firms to compete in the Canadian dredging market. Finally, EU vessels can undertake some transshipment activity in Canada but this is limited to international cargo on the specific Montreal-Halifax route. The paper attempts to highlight some possible CETA’s consequences for domestic Canadian shipping markets. It uses industrial economics analytical tools drawn from a Structure-Conduct-Performance (SCP) paradigm. From a literature review, it reconstructs different cases of deregulation that occurred internationally. The observed transformations are then characterized in terms of the SCP model. The paper identifies some common impacts which occurred in different transportation industries after a deregulation process. Using these findings, it concludes by discussing potential impacts for domestic shipping markets in Canada. 相似文献
33.
The study is based on a literature review of recent empirical research on crew resource management (CRM) training in the maritime industry, organised around what non-technical skills to learn and how. The review indicates that existing work is dominated by individualistic theories of learning with less focus on learning as a social process. Five main categories of skills that need to be trained are identified: assertiveness, decision-making, communication, situation awareness and team coordination. We argue that it is necessary to operationalise these broad concepts further, emphasising the work context and crew-specific needs. The review also shows that a combination of classroom lectures and simulator-based exercises is commonly used in maritime education and training in these skills. The learning effect seems to be suffering from training programmes that are exported ‘as is’ from aviation and not adjusted to the maritime domain or to operation-specific needs. This paper examines maritime crew resource management training from a social learning perspective, involving the view that learning is a context bound, social process that might take place in communities of practice (CoP). A CoP is a group (e.g. a crew) wherein members share an activity and learn from each other. It is argued that CRM training programmes will benefit from including a social learning perspective. Factors that enable the assessment of teams are discussed, and it is argued that the training should be tailored to existing crews, emphasising a learning environment as close to reality as possible. 相似文献
34.
35.
This paper proposes a recursive least squares algorithm for a nonlinear additive system with time delay. By the Weierstrass approximation theorem and the key term separation principle, the model can be simplified as an identification model. Based on the identification model, a recursive least squares identification algorithm is used to estimate all the unknown parameters of the time-delayed additive system. An example is provided to show the effectiveness of the proposed algorithm. 相似文献
36.
Along with higher and higher integration of intellectual properties (IPs) on a single chip, traditional bus-based system-on-chips (SoC) meets several design difficulties (such as low scalability, high power consumption, packet latency and clock tree problem). As a promising solution, network-on-chips (NoC) has been proposed and widely studied. In this work, a novel algorithm for NoC topology synthesis, which is decomposing and cluster refinement (DCR) algorithm, has been proposed to minimize the total power consumption of application-specific NoC. This algorithm is composed of two stages: decomposing with cluster generation, and cluster refinement. For partitioning and cluster generation, an initial low-power solution for NoC topology is generated. For cluster refinement, the clustering is optimized by performing floorplan to further reduce power consumption. Meanwhile, a good tradeoff between power consumption and CPU time can be achieved. Experimental results show that the proposed method outperforms the existing work. 相似文献
37.
张传勇 《上海交通大学学报(英文版)》2016,21(1):33-43
As more and more Chinese and foreign-funded banks settle in the China (Shanghai) Pilot Free Trade Zone (CSPFTZ), it has become an imperative to enhance risk management of offshore banking. At the international level, the regulatory effort for offshore banking mainly focuses on tax evasion and money laundering. Existing regulatory frameworks have established standards to identify countries providing facilities for money laundering and developed punitive measures. In terms of strategy, it is suggested that, firstly, relevant regulatory measures should be improved in the short term, and it is necessary to define the scope of offshore banking and regulatory measures for Chinese banks and foreign-funded banks under a suitable legal framework. Secondly, it is necessary to establish risk exposure mechanism and risk evaluation system for the offshore banking in the CSPFTZ, while risk management measures are implemented based on on-site supervision. Thirdly, in the medium and long term, it is necessary to enhance management of potential risks which can be created by offshore banking due to deregulation. Fourthly, on the one hand, specific regulations should be formulated to provide a regulatory basis for taxation; on the other hand, tax informational exchange agreements (TIEAs) may be used as a reference for achieving effective tax regulation. 相似文献
38.
Paul Musili Wambua 《WMU Journal of Maritime Affairs》2012,11(1):95-113
Since 2008 Kenya has distinguished itself in the global war against piracy by undertaking prosecutions in the national courts
of suspected pirates arrested in the high seas and handed over by navies of leading maritime nations under bilateral agreements
(MOUs) entered into between Kenya and these leading maritime nations. As of July 2011, Kenya had over 20 convicted pirates
serving jail terms ranging between 7 and 20 years and over 100 suspected pirates awaiting trial in national courts. This is
the largest number of suspected pirates held and tried in any one state at any given time in modern history. To achieve this,
Kenya had to effect far reaching changes in the law. In the initial stages, suspected pirates were charged under Kenya’s Penal
Code (Cap 63 Laws of Kenya). However, the high court in the case of Re Mohamud Mohamed Dashi and eight others [2010] eKLR,
ruled that Kenya had no jurisdiction to try suspected pirates under that law. In September 2009, Kenya passed a new law (the
Merchant Shipping Act), which not only defined more comprehensively and extensively the offence of piracy, but also extended
the jurisdiction of Kenyan courts to try piracy committed by non-nationals. Though the law gives Kenya a very broad jurisdiction
to try suspected pirates, the process is still fraught with challenges due to lack of financial and human resources. In the
case of Republic vs Hassan Jama Haleys Alias Hassan Jamal and five others [2010] eKLR, the court commented thus:
“… I must note that the ‘piracy trials’ have presented a unique challenge to the Kenyan legal system. We cannot ignore the fact that these are suspects who having been arrested by foreign naval forces on the High Seas are brought to Kenya for trial. They are strangers in the country, do not understand the legal system, may not know what their rights are and do not understand the language… the Kenyan Government and the International partners supporting these trials put in place a system to provide free legal representation for the suspects…” 相似文献
39.
A novel type of control law was adopted to reduce the vertical acceleration of a fast ferry as well as the motion sickness incidence suffered by the passengers onboard by means of a submerged T-foil. Considering the system changing characteristics under high disturbances, a model-free approach was adopted. In addition, an upgraded proportional-derivative (PD) controller with correction terms resulting from a fast-online estimation of the system dynamics was designed. The overall controller, known as intelligent PD (i-PD) controller, was tested, and the obtained results were compared with those of a classic PD controller. The controllers were also tested in a changing environment and at different operating velocities. The results confirmed the effectiveness of the i-PD controller to smooth the motions with low computational cost control schemes. Furthermore, thanks to ability of the i-PD controller to continually update the estimated dynamics of the system, it showed a better reduction in both vertical motions and the seasickness level of the passengers with the needed robustness under external disturbances and system changing parameters. 相似文献
40.
Full duplex communication highly improves spectrum efficiency of a wireless communication link. However, when it is applied to a cellular network, the capacity gain from this technology remains unknown. The reason is that full duplex communication changes the aggregate interference experienced by each communication link in cellular networks. In this paper, the capacity gain from full duplex communication is studied for cellular networks of 4G and beyond, where the same frequency channel is adopted in each cell. A two-layer Poisson point process (PPP) is adopted to model the network topology, and stochastic geometry is employed to derive the coverage probability and the average capacity of typical link in a cellular network. On the basis of these derived parameters, the capacity gain from full duplex communication is determined. Numerical results reveal that without mutual interference cancellation (MIC), the capacity gain is small under various power levels; with perfect MIC at base stations, the capacity gain can exceed 60%; with imperfect MIC at base stations, the capacity gain decreases quickly even with a slight drop of MIC performance. 相似文献