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This paper develops a cluster-led strategic policy framework to assess the strategic positioning of key global logistics cities in Asia, most of which are affected by the ‘Belt and Road (B&R) Initiative.’ One of the key challenges that the B&R Initiative is facing is underdeveloped logistics infrastructure in Asia, not to mention road congestion, dilapidated infrastructure, incessant supply chain disruptions, and capacity constraint, which imposes significant economic costs.

Global logistics cities are evaluated on logistics infrastructure capacity and service responsiveness. This involves selecting the key global logistics cities, identifying key indicators, standardising and indexing, mapping dimensions of global logistics cities, and developing the cluster-led strategic policy framework.

The results indicate the prevalence of a multi-tier system wherein Shanghai and Hong Kong have attained the maturity of a global logistics city, whilst Manila, Jakarta, and Bangalore are making slow but steady progress in that direction. In contrast, Dhaka, Phnom Penh, and Ho Chi Minh City are showing potential but require further enhancement through significant investment in infrastructure and service delivery improvement.

The cluster-led strategic policy framework formulates actions and strategies through which emergent logistics networks can be strategically aligned and functionally integrated with B&R-oriented global trading hubs and transport corridors..  相似文献   


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The galvanic corrosion behaviour of aluminium 3004 and copper with different area ratios were studied in the tropical marine atmosphere at Tuticorin harbour over a period of 426 days. The area ratios of AAl : ACu, studied were 1:1, 1:2, 1:4, 1:8, 2:1, 4:1 8:1. The galvanic corrosion behaviour of metals was studied in terms of relative increase in the corrosion rate of aluminium due to galvanic coupling with copper, relative decrease in the corrosion rate of copper due to galvanic coupling with aluminium, and the susceptibility of aluminium to pitting owing to galvanic coupling with copper. The galvanic potential and galvanic current of the system were monitored. Pits of different dimensions ranging from mild etchings to perforations were experienced on the borders and the surfaces of the interface of aluminium in contact with copper. The weathering parameters and the environmental pollutants which have a major role in influencing the galvanic corrosion of metals were also monitored. The corrosion products resulting from galvanic corrosion were analysed using XRD and the pitting on aluminium resulting from galvanic corrosion has been highlighted in terms of pit depth, size and density of pit, using a high resolution microscope.  相似文献   

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The galvanic corrosion behaviour of aluminium 3004 and copper with different area ratios were studied in the tropical marine atmosphere at Tuticorin harbour over a period of 426 days. The area ratios OfAAI: Acu, studied were l:l, 1:2, l:4, 1:8, 2:1, 4:1 & 8:1. The galvanic corrosion behaviour of metals was studied in terms of relative increase in the corrosion rate of aluminium due to galvanic coupling with copper, relative decrease in the corrosion rate of copper due to galvanic coupling with aluminium, and the susceptibility of aluminium to pitting owing to galvanic coupling with copper, The galvanic potential and galvanic current of the system were monitored. Pits of different dimensions ranging from mild etchings to perforations were experienced on the borders and the surfaces of the interface of aluminium in contact with copper. The weathering parameters and the environmental pollutants which have a major role in influencing the galvanic corrosion of metals were also monitored. The corrosion products resulting from galvanic corrosion were analysed using XRD and the pitting on aluminium resulting from galvanic corrosion has been highlighted in terms of pit depth, size and density of pit, using a high resolution microscope.  相似文献   

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浪况对大型船舶轴系轴承垂向偏移与负荷的影响   总被引:1,自引:1,他引:0  
以某8000TEU集装箱船为研究对象,利用有限元法在ANASYS中建立船体模型。通过设计浪频、浪向、波高与相位对轴承垂向偏移影响的正交仿真计算,并利用极差分析法、层次分析法和模糊综合评判法对实验进行分析,结果表明:这4种因素对轴承垂向偏移的影响程度是浪频:浪向:波高:相位=0.303: 0.071: 0.533: 0.093;在海浪的影响下,靠近主机的两个中间轴承的相对垂向偏移最大。为了进一步分析波浪对轴承负荷的影响,利用轴系校中理论,计算得到轴承在有无海浪影响下的负荷大小并进行比较,结果表明:大型船舶在海浪中行驶时,对尾轴承负荷的影响较大,在轴系校中计算中应予以关注。  相似文献   

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Previous trend studies have shown increasing nitrogen and phosphorus as well as decreasing silica concentrations in the water mass of the Baltic Sea. This has had an impact on the amount of primary production, but also on the quality and succession of plankton species. Present study examines the spatial and temporal patterns of potential nutrient limitations in the Baltic Sea for the time period 1970–2000. Generally, low concentrations of DSi can limit the diatom blooms and such conditions are found in the Gulf of Riga and Gulf of Finland during spring and summer. Nutrient ratios, DSi:DIN, DSi:DIP and DIN:DIP, are often used to determine which nutrient may limit the primary production. Annual long-term temporal trends of silica to inorganic nitrogen and phosphorus respectively show consistent decreasing patterns. The largest slopes are detected during spring and summer for DSi:DIN and during spring for DSi:DIP ratios. For the DIN:DIP ratio significant slopes are only found in a few locations despite increasing levels for both nutrients, displaying a large variation in trends. In the open Baltic Proper the present trends are positive during winter and negative during spring and autumn. Gulf of Finland and Gulf of Riga are areas where both DSi:DIP and DSi:DIN ratios are found close to the Redfield ratios for diatoms. Together with the evaluated trends these suggest that the Gulfs may become silica limited in a relatively near future. These findings give some implications on the development and impact of changing nutrient concentrations.  相似文献   

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Parameterisation of clastic sediments including benthic structures   总被引:1,自引:0,他引:1  
The sediment transport processes in the south-western Baltic Sea are predicted by means of a numerical model in the project DYNAS. There are two sediment parameters that influence the results of modelling remarkably: critical shear stress velocity and bottom roughness. This paper presents the way how to parameterise these factors and extrapolate them into the investigation area. The critical shear stress velocity is parameterised basing on grain size data, combining approximations after Hjulström [Hjulström, F., 1935: Studies in the morphological activity of rivers as illustrated by the river Fyris. Geological Institution of University of Uppsala: Bulletin (25): 221–528.], Shields [Shields, A., 1936: Anwendung der Ähnlichkeits-Mechanik und der Turbulenzforschung auf die Geschiebebewegung. Mitteilungen der Preussischen Versuchsanstalt für Wasserbau und Schiffahrt (26): 26 pp.] and Bohling [Bohling, B., 2003: Untersuchungen zur Mobilität natürlicher und anthropogener Sedimente in der Mecklenburger Bucht. unpublished doctoral thesis, Mathematisch-Naturwissenschaftliche Fakultät, Ernst-Moritz-Arndt-Universität Greifswald/Germany, 156 pp.]. The roughness length, in the case of absence of macro zoo-benthos and their structures, is parameterised basing on grain size too employing Soulsby [Soulsby, R.L., 1997: Dynamics of Marine Sands: a Manual for Practical Applications. London, Thomas Telford Publications. 249 pp.], Nielsen [Nielsen, P., 1983: Analytical determination of nearshore wave height variation due to refraction shoaling and friction. Coastal Engineering 7, 233–251.] and Yalin [Yalin, M.S., 1977: Mechanics of Sediment Transport. Pergamon Press, New York. 298 pp.]. No equivalent simple parameterisations for biologically caused bed roughness exist. Here, findings of Friedrichs [Friedrichs, M., 2004: Flow-induced effects of macro zoo-benthic structures on the near-bed sediment transport. Dissertation, Universität Rostock, 80 S.] and estimations by the DYNAS biologists group were combined in order to derive roughness lengths from abundance measurements of four previously selected key species which represent the originators of the dominating benthic structures at the sea floor in the south-western Baltic Sea. Critical shear stress velocity and bed roughness are known at few sample sites only. They were extrapolated into the larger investigation area using a proxy-target concept. The mean near bottom milieu (bathymetry, median grain size, salinity, oxygen) which was derived using results from numerical modelling serves as the proxy. Since the milieu parameters are measured at the sampling sites for which the target parameters have been determined, a combined hierarchical and supervised classification was employed to transfer the local knowledge into the unknown investigation area.  相似文献   

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In this study,a 2kHz Tonpilz projector was designed using a Terfenol-D and modeled in ATILA.For the purpose of modeling studies,it has been determined that a radiating head mass exhibits better transmitting current response(TCR) at 136 mm diameter,where the resonance occurs at 2.4kHz and the peak value of 118 dB re 1 μPa/A at 1 m occurs at 12 kHz.Also bolt at a 46mm distance from the center of the head mass offers resonance at 2.4kHz,and the peak value of 115.3 dB re 1 μPa/A at 1m occurs at 11.5kHz.This optimized design is fabricated and molded with polyurethane of 3mm thickness.The prototype was tested at the Acoustic Test Facility(ATF) of National Institute of Ocean Technology(NIOT) for its underwater performances.Based on the result,the fundamental resonance was determined to be 2.18kHz and the peak value of TCR of 182 dB re 1 μPa/A at 1m occurs at 14 kHz.The maximum value of the RS was found to be -190 dB re 1V/μPa at 1m at a frequency of 2.1kHz.  相似文献   

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 In order to accumulate knowledge about how material compositions and manufacturing methods affect fatigue strength, this paper investigates the relationship between the swiftness of the changes in the macroscopic indices of the crack initiation process and the hardening properties of a material. This is done by calculating the cyclic deformation behavior of a f.c.c. single crystal. The relationship between the swiftness of the changes and the crystal geometries is also examined by calculating the deformation behavior of a f.c.c. crystal with a high Schmid factor buried in a large crystal with a low Schmid factor. In addition, a multiscale hardening rule based on forest theory is developed in order to examine the microscopic mechanisms of fatigue slip band (persistent slip bands, PSBs) formation. The validity of the theories presented is examined by comparing the changing nature of the measured and calculated hysteresis loop shapes of f.c.c. single crystals. Inhomogenous slip deformation through the crystal is also investigated, and inferences are then drawn about the microscopic mechanisms of cyclic hardening and PSB formation. Received: August 5, 2002 / Accepted: December 18, 2002 Address correspondence to: N. Osawa (osawa@naoe.eng.osaka-u.ac.jp) Updated from the Japanese original, which won the 2002 SNAJ prize (J Soc Nav Archit Jpn 1998;184:351–363, 1999;185:283–292 and 186:535–544, 2001;190:539–551)  相似文献   

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Journal of Marine Science and Technology - A correction to this paper has been published: https://doi.org/10.1007/s00773-021-00807-z  相似文献   

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In addition to sulphur oxides control, the North and the Baltic Seas have recently been designated as nitrogen oxides control area. Amidst ongoing developments in energy markets and international trade, shipowners have to develop cost-efficient strategies to comply with the new regulation. This study creates and tests a model calculating the incremental costs of abating NOx and SOx emissions under MARPOL Annex VI regulations for the following methods: SCR, HAM and internal engine modifications, marine gas oil, wet scrubbers, and liquefied natural gas propulsion. The model is tested empirically on a broad sample of 244 ships from the Swedish Commercial Fleet database for different operating contexts and fuel prices. Individual ship emission reductions and incremental abatement costs are calculated and the results are presented for the entire studied sample and per ship type class.

The study also explores the sensitivity of the chosen abatement methods to cost determinants and to main engine time operation under the light of economic performance and cost-efficiency. The results of the study aim to contribute to company abatement strategy.  相似文献   


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Treaties on Trial: The Continuing Controversy Over Northwest Indian Fishing Rights by Fay G. Cohen (Seattle: University of Washington Press, 1986), 229 pages.  相似文献   

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着重介绍了小型LNG运输船货物系统的基本作业流程。主要分析了装货前作业:货舱处所干燥、干燥与惰化、充气及预冷;正常装卸货航行作业:装货作业、装货航行、卸货作业及压载航行;卸货进坞前作业:扫舱、暖舱、惰化及驱气。这为各作业流程所对应的管路系统的初始设计明确了需要达到的功能,同时强调了熟悉作业流程对小型LNG运输船货物系统设计的重要性。  相似文献   

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The objective of this research was to examine if certain strains of Bacillus bacteria, could survive in dry powder products and if so, could the bacteria degrade organic contaminants in saline wastewater on a ship. As part of the study, we isolated 7 domesticated strains named NY1, NY2,..., and NY7, the strain NY6 showed to have the best performance for organic matter degradation and could survive in dry powder more than 3 months. NY6 was identified as Bacillus aerius, based on the morphological and physic-chemical properties. Its optimal growth conditions were as follows: salinity was 2%; temperature was 37°C; pH was in 6.5–7.0; best ratio of C: N: P was 100:5:1. The capability of its dry powder for Chemical Oxygen Demand (COD) removal was 800mg COD/g in synthesized marine wastewater with 2% salinity. The spores in the dry powder were 1.972×108 g ?1.  相似文献   

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