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1.
Transportation - Predicting how changes to the urban environment layout will affect the spatial distribution of pedestrian flows is important for environmental, social and economic sustainability....  相似文献   
2.
The planning and development of pedestrian and cycling amenities in coastal urban environments is a challenging process because a wide range of policies and considerations must be taken into account. Among these, the concepts of sustainability and more recently, resilience, have been gaining prominence. Green Infrastructure design approaches can integrate aspects of both sustainability and resilience, providing multiple services within single development projects. This study focuses on Dublin and examines a range of amenity projects at various stages of development that relate to the provision of new coastal walking and/or cycle routes. These are initially contextualized at the city level before focusing specifically on challenges and benefits associated with the design and implementation of such projects. Based on our findings, recommendations are made for optimizing the potential of future projects to effectively integrate with other initiatives so as to deliver broader policy objectives. A simple sequential model is presented that should assist developers and decision-makers to take a more integrated, multidisciplinary approach to meeting policy goals when planning and developing coastal amenities. Finally, this is remodeled into a set of considerations that are generally applicable to coastal development proposals of significant scale.  相似文献   
3.
REGULATIONOFPRODUCTIONOFPARATHYROIDHORMONE-RELATEDPEPTIDE(PTHrP)ANDEXPRESSIONOFITSmRNAINAHUMANLIVER-DERIVEDCELLLINELiHusong;P...  相似文献   
4.
管道技术     
全世界正在以前所未有的速度消耗着石油和天然气,因此,需要以成本效益的方式开发新的资源。然而,最近管道设计公司面临更具挑战性的海上和海底环境,从而需要采取新的方式来克服不寻常的设计挑战  相似文献   
5.
This article explores how a fresh approach to integrated coastal zone management (ICZM) in Ireland might be forged through the identification of a number of key innovative cross-sectoral professional initiatives and interdisciplinary academic thinking in this sector. It includes three interlinked research themes that assess existing cross-sectoral data management issues (to include an assessment of readiness for the INSPIRE and compliance with the Re-use of Public Sector Information European Union Directives), the degree of cross-pollination between the various sectors involved in managing the Irish Coastal Zone (to identify the need (or otherwise) for capacity- building to encourage cross-fertilization of ideas, skills, and knowledge exchange), and cross-professional competencies (to assess the desire/need (if any) for those working in coastal zone management to add to their existing competencies through continuous professional development or lifelong learning opportunities). Indeed, the specific competencies for coastal practitioners are identified here and these further illustrate the need for professional recognition of the role, responsibilities, and therefore the requirement for an appropriately qualified “Coastal Manager” professional, one that is seen not merely as a nicety but rather a necessity—a core enabler in any future innovative and integrative management approach.  相似文献   
6.
Abstract

Major air pollutants from maritime shipping operations are sulfur oxides, nitrogen oxides, and particulate matter emissions from combustion of fuel oil during cruise, berth, and start‐up modes. Sulfur oxides emissions are substantial from steamships burning high‐sulfur residual fuel oil, where shipping contributes 66 percent of the total sulfur dioxide emissions from transportation sources, and almost 3 percent of the total for Harris county, Texas. Nitrogen oxides emissions are significant during cruise conditions for both steamships and motor ships, while particulate emissions are substantial during start‐up and tube cleaning.

Significant marine air pollutant emission sources are found in busy harbor areas such as the Houston Ship Channel. Offshore terminals for unloading large tankers may result in emissions of 10 to 20 tons of sulfur oxides daily per ship, and 3 to 5 tons of nitrogen oxides daily per ship during pumping operations. Trace‐metal constituents present in the oil may catalyze sulfur dioxide and nitrogen dioxide oxidation to their respective sulfate and nitrate aerosols in the humid Texas Gulf Coast atmospheres to aggravate photochemical air pollution problems once the air masses reach industrial and populated urban areas on land. Onshore sulfur dioxide and particulate‐matter emission controls may be necessary for some large ships in port to minimize potential impact on coastal zone air quality.  相似文献   
7.
Monte Carlo analyses are generally considered the standard for uncertainty analysis. While accurate, these analyses can be expensive computationally. Recently, polynomial chaos has been proposed as an alternative approach to the estimation of uncertainty distributions (Hosder et al. A non-intrusive polynomial chaos method for uncertainty propagation in CFD simulations. In: 44th AIAA aerospace sciences meeting and exhibit, Reno, Nevada, 2006; Wu et al. Uncertainty analysis for parametric roll using non-intrusive polynomial chaos. In: Proceedings of the 12th international ship stability workshop, Washington, DC, USA, 2011). This approach works by representing the function as a series of orthogonal polynomials; the weights for which can be calculated via several methods. Previous studies have demonstrated the usefulness of this technique for comparatively simple systems such as parametric roll modeled by the Mathieu equation with normally distributed parameter values (Wu et al. Uncertainty analysis for parametric roll using non-intrusive polynomial chaos. In: Proceedings of the 12th international ship stability workshop, Washington, DC, USA, 2011). In the present work, a polynomial chaos method is applied to a nonlinear computational ship dynamics model with normally distributed input parameters. Test cases were selected where parametric roll was expected to potentially occur. The resulting probability distributions are compared to the results of a Monte Carlo analysis. In general, these results demonstrate good agreement between Monte Carlo simulation and polynomial chaos in the absence of capsize with significant computation gains found with polynomial chaos. Overall, we conclude that polynomial chaos is an effective tool for reducing simulation time costs when studying parametric roll, and potentially other ship dynamics phenomena, particularly in the absence of capsize-like bifurcations.  相似文献   
8.
The success of any coastal zone management policy is dependent on, among other things, effective legislation and its enforcement. This article examines some possible legal constraints on the implementation of an integrated coastal zone management policy in Ireland. An introduction to the existing legal framework is provided, and the inconsistencies and ambiguities related, in particular, to jurisdiction and area of responsibility are highlighted. In particular the effect of land ownership and property rights on coastal zone management are examined with reference to two popular resort beaches in County Donegal, Ireland. While a revision of the relevant legislation is desirable, it is probably unrealistic; however, powers are available to the various institutions involved in coastal management that are currently unused. These are reviewed and their potential to improve coastal zone management is discussed.  相似文献   
9.
Large-volume sampling of 234Th was conducted to estimate particulate organic carbon (POC) export in conjunction with drifting sediment trap deployments in the northern Barents Sea in July 2003 and May 2005. 234Th-derived POC fluxes averaged 42.3 ± 39.7 mmol C m− 2 d− 1 in 2003 and 47.1 ± 30.6 mmol C m− 2 d− 1 in 2005. Sediment trap POC fluxes averaged 13.1 ± 8.2 mmol C m− 2 d− 1 in 2003 and 17.3 ± 11.4 mmol C m− 2 d− 1 in 2005, but better reflected the transient bloom conditions that were observed at each station within a season. Although 234Th fluxes agreed within a factor 2 at most stations and depths sampled, sediment trap POC fluxes were lower than large-volume POC flux estimates at almost every station. This may represent an under-collection of POC by the drifting sediment traps or, conversely, an over-collection of POC by the large-volume sampling of 234Th. It is hypothesized that the offset between the two methods is partly due to the presence of the prymnesiophyte Phaeocystis pouchetii, which potentially causes a large variation in > 53-μm POC/234Th ratios. Due to the large proportion of dissolved carbon or mucilage released by P. pouchetii, and because it is thought that P. pouchetii does not contribute significantly to the vertical export of biogenic matter in the Barents Sea, the application of large-volume sampling of 234Th may yield relatively high, and possibly inaccurate POC/234Th ratios. Hence, POC fluxes derived from 234Th sampling may be inappropriate and drifting sediment traps might be a more reliable method to measure the vertical export of biogenic matter in regions that have recurrent P. pouchetii blooms, such as the Barents Sea.  相似文献   
10.
Transportation - Transportation network companies (TNCs), such as Uber and Lyft, have been hypothesized to both complement and compete with public transit. Existing research on the topic is limited...  相似文献   
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