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971.
We develop an integrated model for estimating the internal cost of abyssal seafloor waste isolation. The model captures the major economic, engineering, geographic and social factors that influence the management cost for sewage sludge and municipal incinerator ash. Considering five representative metropolitan areas and five proposed abyssal study sites, we apply this model to produce cost estimates for four deep-ocean waste delivery system concepts. The results show that the unit cost depends primarily on regional waste volume, the marine delivery system and transportation distance. Based on available data, the abyssal ocean option may be competitive with present land-based disposal costs in New York City. The option is less competitive in other metropolitan areas.  相似文献   
972.
鞠秀山  吕建明 《天津航海》2007,(3):32-33,42
船员在船舶进行维修保养工作期间,经常发生一些工伤、机损事故。此文就如何加强安全防范意识,避免发生人身伤害和设备损坏提出了建议和措施。  相似文献   
973.
Sea surface temperature fields of the North Sea and Baltic Sea have been constructed for the year 2001 using a multiplatform Optimal Interpolation scheme. The analyzed fields are constructed every 12 h on a 10 km spatial grid. The product is based upon observations from the three NOAA satellites 12, 14 and 16 together with a large amount of in situ observations. Space dependent covariance functions are estimated from the satellite observations and account for spatial and temporal lags. Several independent methods have been used to assess the error on the sea surface temperature product. Compared against independent in situ observations, the mean RMS difference for the year 2001 is 0.78 °C. The spatial distribution of the errors reveals that the Baltic Sea in general show higher errors than the North Sea. The error statistics throughout the year show a temporal variation of the errors with maximum during summer and winter. Tests with a varying number of satellite observations show that the accuracy of the satellite observations is the most important parameter in terms of reducing the errors on the interpolated sea surface temperature product.  相似文献   
974.
舰船设备抗冲击性能校核评估系统概念设计   总被引:1,自引:0,他引:1  
通过对舰船设备冲击试验现状以及计算机建模仿真水平的研究分析,论证了开发舰船设备抗冲击性能校核评估系统的必要性和可行性.根据舰船设备抗冲击仿真计算的要求和特点,提出了舰船设备抗冲击性能校核评估系统应当具备的基本功能和总体构架,并分别对系统各模块的功能特性和相互关系进行了较为细致的研究分析.在系统的设计过程中采取了一系列优化的措施,以最大限度地提高系统的运行效率和可靠性,为下一步开发舰船设备抗冲击性能校核评估系统奠定了基础.  相似文献   
975.
The Gulf of California hosts astounding biodiversity that supports numerous economic activities in the region. These activities, and emerging threats, are placing pressure on the region's ecosystems. Government and civil society are working to address threats through several conservation and management mechanisms. Nevertheless, the use and incorporation of scientific information—a key component for creating effective and durable management—is still deficient. This article presents the concept of science integration and discusses the findings of a study that assesses the regional landscape, existing institutional arrangements, and capacity for using science to inform policy and management decisions. It also explores the current use of science within fisheries policy and management and the capacity of the National Network of Information and Research of Fisheries and Aquaculture (RENIIPA) and the State Fisheries and Aquaculture Councils, two mechanisms in the region. Finally, it shares lessons learned and offers recommendations on how the region can strengthen science-based decision-making. Results indicate that while there are some actors in the Gulf of California producing relevant science, there is varying capacity of intermediary groups connecting producers with users of science, or mechanisms in place to ensure that science is being utilized in decision-making processes. Moreover, despite having a well-developed landscape of producers and intermediaries and mechanisms in place for fisheries management in the region, effective science integration is not occurring.  相似文献   
976.
梁友庆  王恒财  郑律 《船舶》2016,27(5):98-100
在明确了分段精度控制意义及概念的前提下,对分段精度控制计划和精度控制管理过程作了详细分析,并制定相应的控制方法。首先针对舵臂分段,根据其尾部曲率较大以及不规则性,依据挂舵垂直性控制其精度;然后针对尾轴分段,根据同心度和尾轴管的定位控制该分段的精度;再针对主基座分段,主要根据基座面板水平度来控制该分段的精度;最后总结出典型分段精度控制方法。  相似文献   
977.
隧道监控系统软件设计与实现   总被引:1,自引:0,他引:1  
隧道监控系统软件开发平台主要分为组态与非组态两种,文中分析了两种平台各自的优缺点,提出采用组态与非组态组合开发的方案,并结合诸永高速公路东阳隧道群监控系统的开发对软件模块的设计和实现方法进行了详细阐述。  相似文献   
978.
In the present study a novel modeling approach is presented to solve the combined internal sloshing and sea-keeping problem. The model deals with interesting effects arising due to the coupled interaction between the sloshing in partially filled containers of several geometries and the ship motion. The study is very important for the liquid cargo carrier operating in rough sea or under different environmental conditions. The resulting slosh characteristics that include transient pressure variation, free surface profiles and hydrodynamic pressure over the container walls have been reported in this study. In addition, the effects of coupled ship response and sloshing on ship motion parameters have also been investigated. The equations of motion of fluid, considered inviscid, irrotational, and partially compressible, are expressed in terms of the pressure variable alone. A finite difference-based iterative time-stepping technique is employed to advance the coupled solution in the time domain. Several parameters of interest, including the container parameters, level of liquid, thrusters modeling and some important environmental factors are investigated.  相似文献   
979.
The effect of interactions between individual fronds in a bed of the large intertidal seaweed Durvillaea antarctica, when forced by breaking waves, is studied using a computational model. The model simulates the response of a seaweed bed using a sequence of connected oscillators which are excited by a propagating forcing function representing a breaking ocean wave. Two new facets of the interplay between seaweeds and hydrodynamics are considered: (i) wave forcing due to breaking waves is often not sinusoidal in the rocky intertidal zone and (ii) a frond interaction term is included. The addition of frond interaction reduces the maximum loading on individuals within the bed by around 30% using estimated biomechanical parameters. The rate of change of the loading on the holdfast (equivalent to the “jerk”) is affected in a similar or greater fashion.  相似文献   
980.
Abstract

Marine and coastal zone policy represents a collaboration of people managing and people managed. This paper takes a holistic stance in suggesting that marine communities are viewed properly as networks of focused interest groups, policymakers, professionals, and publics. The interplay between culture and marine and coastal policy is appropriately one topic of applied social research. Seven ethnographic studies in this domain are introduced in this theme issue and help us to understand sociocultural processes and institutions bearing on marine affairs.  相似文献   
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