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1.
重点分析了西安局集团公司由2K数调主系统组网更新改造为FAS双中心网络的建设方法,并根据日常维护经验,列举了调度台通道故障处理、FASB简易故障判断及计表倒换试验、FASA和FASB系统与MSC之间的业务故障处理等.  相似文献   
2.
求解多峰性函数全局最优解的进化算法及其应用研究   总被引:11,自引:0,他引:11  
本又针对简单遗传算法(SGA)在解决多峰性函数最优化问题存在的不足,提出了一种分配区间型进化算法,能够求出多峰性函数所有全局最优解及多个局部最优解。通过十几个多峰性函数与工程实例的数值实验,验证了算法的正确性。对简易海洋平台进行了疲劳可靠性优化设计为算例,取得了满意的结果。  相似文献   
3.
张世秀  王平 《舰船电子工程》2009,29(12):97-99,152
为提高海缆的通信保障能力,采用全球定位系统(GPS)和地理信息系统(GIS)技术,设计海缆巡线管理系统。该系统分为数据采集、数据传送和数据中心管理三个组成部分,对巡线员和数据管理员的工作流程进行了具体描述,并分析了系统实现的关键技术;对数据传送的前端硬件系统组成和实现原理进行了详细设计和分析,实现了规范化管理和科学化监督的预期目标。  相似文献   
4.
Geographical Information Systems (GIS) are important took for environmental monitoring and management. However, their limitations in dealing with complex, dynamic, and mission‐critical situations call for alternative approaches. Integrating GIS with dynamic simulation models offers one such solution. Numerical models that simulate physical, chemical, and biological processes greatly increase our understanding of the environment. Many of these models use refined forecast information to accurately predict processes that help in monitoring and managing the environment. Integrating these models with GIS offers new functionalities. The present research couples the MIKE21 comprehensive modeling system for two‐dimensional free surface flows with the spatial analysis strengths of the ArcView GIS. The southern coastal water system of Singapore serves as the study area. The aim is to develop a comprehensive software system that provides support for both environmental managers and land‐use planners in making their decisions.  相似文献   
5.
船舶结构混合变量优化的遗传算法   总被引:10,自引:2,他引:8  
本文针对船舶结构优化设计中普遍存在的混合离散变量现象,对遗传算法进行了若干探讨和改进,以直接获得实用的最优解。通过两个船舶结构优化的算例,验证了本文方法的有效性。  相似文献   
6.
This paper presents a global ocean implementation of a multi-component model of marine pelagic biogeochemistry coupled on-line with an ocean general circulation model forced with climatological surface fields (PELAgic biogeochemistry for Global Ocean Simulations, PELAGOS). The final objective is the inclusion of this model as a component in an Earth System model for climate studies. The pelagic model is based on a functional stoichiometric representation of marine biogeochemical cycles and allows simulating the dynamics of C, N, P, Si, O and Fe taking into account the variation of their elemental ratios in the functional groups. The model also includes a parameterization of variable chlorophyll/carbon ratio in phytoplankton, carrying chl as a prognostic variable. The first part of the paper analyzes the contribution of non-local advective–diffusive terms and local vertical processes to the simulated chl distributions. The comparison of the three experiments shows that the mean chl distribution at higher latitudes is largely determined by mixing processes, while vertical advection controls the distribution in the equatorial upwelling regions. Horizontal advective and diffusive processes are necessary mechanisms for the shape of chl distribution in the sub-tropical Pacific. In the second part, the results have been compared with existing datasets of satellite-derived chlorophyll, surface nutrients, estimates of phytoplankton community composition and primary production data. The agreement is reasonable both in terms of the spatial distribution of annual means and of the seasonal variability in different dynamical oceanographic regions. Results indicate that some of the model biases in chl and surface nutrients distributions can be related to deficiencies in the simulation of physical processes such as advection and mixing. Other discrepancies are attributed to inadequate parameterizations of phytoplankton functional groups. The model has skill in reproducing the overall distribution of large and small phytoplankton but tends to underestimate diatoms in the northern higher latitudes and overestimate nanophytoplankton with respect to picoautotrophs in oligotrophic regions. The performance of the model is discussed in the context of its use in climate studies and an approach for improving the parameterization of functional groups in deterministic models is outlined.  相似文献   
7.
In a previously reported study, wind tunnel experiments were undertaken to investigate the aerodynamic characteristics of hybrid-sails in isolation. Such sails are seen as providing a worthwhile reduction in the delivered power to the propeller and hence the engine generated thrust, with a corresponding reduction in the CO2 production of diesel engine exhaust. In this paper, wind tunnel testing is used to investigate sail–sail interaction effects for two sets of four identical hybrid-sails, and the sail–hull interaction effects for the same two sets of four identical sails in the presence of a bulk carrier hullform. The analysis presented suggests that to build a sail-assisted ship requires an appreciation of the sail–sail and sail–hull interaction effects.  相似文献   
8.
王永 《铁道勘察》2003,29(2):33-34
就本单位在城市GPS网及基础测绘项目中GPS测量、GPS数据处理作了介绍和讨论 ,并提出了GPS在测量应用中值得探讨和关注的问题  相似文献   
9.
A 1/32° global ocean nowcast/forecast system has been developed by the Naval Research Laboratory at the Stennis Space Center. It started running at the Naval Oceanographic Office in near real-time on 1 Nov. 2003 and has been running daily in real-time since 1 Mar. 2005. It became an operational system on 6 March 2006, replacing the existing 1/16° system which ceased operation on 12 March 2006. Both systems use the NRL Layered Ocean Model (NLOM) with assimilation of sea surface height from satellite altimeters and sea surface temperature from multi-channel satellite infrared radiometers. Real-time and archived results are available online at http://www.ocean.nrlssc.navy.mil/global_nlom. The 1/32° system has improvements over the earlier system that can be grouped into two categories: (1) better resolution and representation of dynamical processes and (2) design modifications. The design modifications are the result of accrued knowledge since the development of the earlier 1/16° system. The improved horizontal resolution of the 1/32° system has significant dynamical benefits which increase the ability of the model to accurately nowcast and skillfully forecast. At the finer resolution, current pathways and their transports become more accurate, the sea surface height (SSH) variability increases and becomes more realistic and even the global ocean circulation experiences some changes (including inter-basin exchange). These improvements make the 1/32° system a better dynamical interpolator of assimilated satellite altimeter track data, using a one-day model forecast as the first guess. The result is quantitatively more accurate nowcasts, as is illustrated by several model-data comparisons. Based on comparisons with ocean color imagery in the northwestern Arabian Sea and the Gulf of Oman, the 1/32° system has even demonstrated the ability to map small eddies, 25–75 km in diameter, with 70% reliability and a median eddy center location error of 22.5 km, a surprising and unanticipated result from assimilation of altimeter track data. For all of the eddies (50% small eddies), the reliability was 80% and the median eddy center location error was 29 km. The 1/32° system also exhibits improved forecast skill in relation to the 1/16° system. This is due to (a) a more accurate initial condition for the forecast and (b) better resolution and representation of critical dynamical processes (such as upper ocean – topographic coupling via mesoscale flow instabilities) which allow the model to more accurately evolve these features in time while running in forecast mode (forecast atmospheric forcing for the first 5 days, then gradually reverting toward climatology for the remainder of the 30-day forecast period). At 1/32° resolution, forecast SSH generally compares better with unassimilated observations and the anomaly correlation of the forecast SSH exceeds that from persistence by a larger amount than found in the 1/16° system.  相似文献   
10.
全球定位系统(GPS)提供了高精度的位置信息和航向、航速等运动要素,借助这些参数,该文实现了可以控制船舶按照既定路线航行的自动航向控制系统。  相似文献   
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