基于矢量控制的带式输送机能耗控制方法研究

带式输送机系统是散货码头的重要组成部分,而感应电机作为最重要的驱动组成,其运行效率不高,导致了电力能源的浪费.本文从感应电机转子磁场定向角度出发,建立了一种考虑铁损的感应电机新模型,并提出了最大效率矢量控制策略.通过检测或估计电机的电流信号,使得电机运行于最优效率点,从而提高带式输送机系统的整体效率.最后仿真模拟了该控...     

Effect of seaweed proliferation on benthic habitat quality assessed by Sediment Profile Imaging

Changes in sediment quality, with special reference to benthic habitat conditions resulting from macroalgae overgrowth, were studied in the Venice Lagoon, Italy. Data were collected biweekly in spring and summer from 1993 to 1998 and from 2001 to 2002, as part of the macroalgae growth control strategies managed by the Venice Water Authority-Consorzio Venezia Nuova. Benthic habitat conditions were studied by means of Sediment Profile Imaging, which allowed the collection of several variables: aRPD (apparent redox potential discontinuity), prism penetration depth, presence of anoxia on the surface of the sediment, presence of reduced gas bubbles, stage of benthic colonization. All these variables led to the calculation of an environmental index (Organism–Sediment Index, OSI), which was then related to physical variables and macroalgae abundance. Until 1996, the overall benthic habitat of the Venice Lagoon showed almost stressed conditions; from 1997, the seaweed biomass rapidly declined and the OSI increased significantly. The OSI seemed to be affected by seaweed biomass, sediment compactness and water depth. Macroalgae biomass greater than 4.5 kg/m² led to the complete disappearance of stage III of benthic colonization; values as low as 0.70 kg m² already had a severe impact on recolonization. SPI attributes indicated the main mechanisms that could have contributed to the benthic quality: seaweed proliferation is often followed by rapid decay of macroalgae biomass, especially when present in large amounts. The decrease in seaweed biomass often results in oxygen depletion in the water column and thus in the sediment, preventing complete benthic colonization. This research confirms the importance of in situ rapid reconnaissance surveys to assess the impact of eutrophication on the benthic habitat.     

串联式混合动力船舶能源系统运行模式切换策略

为了解决内河电力推进船舶混合动力能源系统运行模式的切换控制问题,以动力电池剩余电量、电池工作温度以及船舶电力推进需求功率作为特征因素,以混合动力能源系统运行模式作为决断输出,建立了基于模糊综合评判方法的船舶混合能源系统运行模式切换控制模型及其控制策略。以实验室的船舶航行工况数据作为试验仿真环境,结果表明,这种方法能够智能地自动切换运行模式,实现了电力推进船舶混合动力能源系统的优化管理,同时能够保证动力电池的工作性能,延长电池寿命。     

FDPSO气体泄露扩散规律数值模拟研究

应用流体动力学理论,通过数值模拟得到了浮式钻井生产储卸油装置(FDPSO)泄露速度、泄露位置、环境风速等因素对气体扩散分布的影响。结果表明,定风速下,气体扩散速度水平方向较垂直方向大,平面内横向较纵向大;不同泄露位置下,气体的扩散分布则主要取决于FDPSO的设备布置情况;不同泄露速度或风速下,气体浓度有着先升高后稳定的变化趋势。同时依据模拟分析结果进行了FDPSO油气处理模块安全逃生路线设计。     

低碳型集装箱港区港内道路规划方案优选

合理的港内道路路网结构及交通组织是集装箱港口作业效率提升以及节能减排的重要保证。提出利用集装箱港区生产作业智能体微观交通仿真模型模拟集装箱生产作业流程,并以集装箱港口服务水平和集卡日均碳排放成本作为指标,优选低碳型集装箱港区港内道路规划方案。应用实例表明,集装箱港区生产作业智能体微观交通仿真模型可有效模拟港内作业过程,通过对比分析不同道路规划方案下的评价指标,得到最优的港内道路规划方案,为港区道路规划与设计提供参考。     

渔船作业安全综合评价方法的研究

运用模糊集理论建立了渔船作业安全的综合评价模型，并运用该模型对渔业公司的生产安全状况进行了评价。结果表明，该模型是合理的，实用的，各级安全管理部门可以用来对渔船的生产作业安全状况进行评估。     

海洋石油平台余热利用研究

东海某DPP平台投产近十五年后,出现设备老化、工艺系统处理量发生变化等情况,从而透平电站、热油锅炉和工艺处理系统出现余热,如何减少能源浪费,及时有效回收利用,需要及时解决问题。通过对基础资料分析研究、平台生产实地调研,提出余热利用方案,并进行成本投资/回报比较,最终验证了方案的正确性。     

Time series for sea water and seaweed of Tc and Sb originating from releases at La Hague

⁹⁹Tc and ¹²⁵Sb have been released in low level liquid waste at the reprocessing plant at La Hague (Fr). Over a number of years data have been obtained on the concentration of ⁹⁹Tc in sea water and in seaweed from sampling locations close to and at increasing distances north and east of the point of release into the English Channel.In addition such data have been obtained on ¹²⁵Sb for a small number of sampling points. These time series, and the information derived from their intercomparison and from comparison with the release data, are presented in this paper.Time series on ⁹⁹Tc as well as ¹²⁵Sb in sea water and seaweed clearly confirm a considerable decrease in release rates at La Hague over the years 1986–1993. Transit times and transfer factors derived from the series are generally in good agreement with the results of modelling efforts. The data do not provide evidence for a time lag between levels of the radionuclides in sea water and those in seaweed longer than a few months.The very high concentration factors for ⁹⁹Tc in brown seaweeds make these seaweeds very useful for environmental monitoring the radionuclide at low release rates and to trace releases in areas remote from the point of release.     

面向多约束的船舶组立构件建造作业调度方法研究

为了提高船舶中小组立等中间产品建造作业调度能力,提升船舶建造效率,提出面向多约束的船舶组立建造作业调度方法。首先,分析船舶组立建造的工艺流程和作业调度方法,综合考虑机器小组、工艺和交货期等多种约束条件,以建造周期最短为调度目标,建立船舶组立建造作业调度数学模型;其次,综合运用算法分解策略及调度规则,设计改进的最短作业优先调度算法实现模型求解;最后,以某船厂建造车间一定生产周期（17天）的中小组立先行中日程计划为对象,验证该方法的有效性和实用性。研究结果表明,所提出的面向多约束的船舶组立建造作业调度方法相较于当前的调度方法,排产周期压缩22小时,即缩短了原有周期的16.18%,有效提高了生产计划排产和作业调度效率。     

液氮远洋渔业综合体--浅谈液氮在远洋渔业中的应用

本文从国内远洋渔业现状出发，大胆地提出一个不同于国内外现有远洋渔业捕捞的技术体系想法---液氮远洋渔业综合体，详细介绍了其构成、存在问题及解决方案等技术要点，为国内远洋渔业的发展提供了重要的价值取向。     

船用转轮除湿空调系统方案的探讨

探讨转轮除湿空调系统在船舶上应用的可行性。在分析干燥剂再生温度和除湿效果的基础上,根据船舶余热的品质和船舶空调的特点,构建了一个船用除湿空调系统。该系统采用单个转轮两级除湿的方案,利用船舶余热作为干燥剂的再生热源,采用海水冷却和压缩式制冷机组冷却相结合的冷却方式,以保证送风温度的稳定。根据所确定的系统方案,建立起船用单个转轮两级除湿空调系统的实验台,用于研究模拟海洋环境下该系统的性能。     

面向船舶分段流水线的多工位协同作业建模技术

为实现船舶分段制造的流水化生产,提高生产效率,提出一种针对车间级的多工位协同制造控制系统,实现针对工位级的精确作业计划。通过分析分段制造工艺数据流、多工位协同作业的特点和关键协同数据,建立以月度生产计划总工期最短为目标的多工位协同作业数学模型。通过搭建仿真验证平台,以上海某船厂的实际案例数据为基础,充分验证模型的正确性,为多工位协同控制系统的建立提供理论依据。     

船舶柴油机主动力装置总能系统能级模型的建立及应用

建立采用排气余热动力回收,热电联产的柴油机船舶主动力装置总能热力系统的能级模型,实例计算表明,采用能级分析法可准确地了解船舶动力装置总能热力系统的能量分配和利用情况.     

小型渔政船线型及附体设计优化

选取某近海小型渔政船典型船型,研究艏艉线型和附体对船舶阻力性能的影响。通过对线型、船型系数以及舭龙骨、压浪板、呆木等常规附体对小型渔政船航行性能的影响进行数值模拟分析,优化船舶线型,针对小型渔政船的功能需求选取合适的附体组合形式,并通过实船运行验证优化后的渔政船航行性能有所改善,达到预期目标,可为同型船舶设计提供参考依据。     

基于虚拟流水的多重约束环境下船体分段车间动态调度

提出了固定位置分段生产和流水式的作业模式结合的分段虚拟流水式建造模式,分析了分段作业-人员-工具-物料-场地多关联约束下的资源调配机制。考虑时间-空间-资源等多重约束,给出了一种基于虚拟流水线生产模式的人员调度算法和场地调度算法,同时以某船厂的实际场地布局和生产建造数据为案例进行了分析讨论。结果表明,提出的算法能够较好的适应分段调度过程的多重约束、动态调整等特点,较大幅度提高分段建造资源的利用效率。     

Optimum routing of a sailing wind farm

To acquire the wind energy of the oceans, a sailing wind farm has been proposed. The wind farm considered is composed of a semisubmersible floating structure, 11 windmills, four sails, six thrusters, and storage for hydrogen. To maximize the acquired energy, an effective algorithm to search for optimum routes was developed. The algorithm is based on the fact that beam winds yield a maximum of acquired energy. This feature reduces the computation time, and, consequently, efficient route optimization becomes possible in a reasonable time. After setting an operational area for the wind farm, navigation simulations for a 1-year period were carried out. A numerical weather forecast was used as well as the responses of the floating structure, such as the speed of the structure, the output power of the windmills, and the time of course changes. In the simulation, the wind farm evades rough seas to avoid structural damage, and an optimum route is searched for. The capacity factor of the system was used to evaluate the efficiency of the optimized routes. From the simulations, the maximum capacity factor achieved was 42.6%. The dependency of the capacity factor on the initial position of the wind farm was also examined. It was shown that offshore from Sanriku in northeastern Japan is an area suited to the operation of the wind farm. The effect of the initial position on consecutive periods of operation is discussed.     

Participating mass in colliding risers

One of the main challenges in estimating impact energy in collisions between marine risers is the assessment of the riser mass involved in the collision. Evidently the entire riser mass does not contribute to the collision. Hence, the question is: What is the equivalent riser mass which contributes to the impact energy? This article presents three different ways of estimating the riser mass participating in the collision energy. The first method is strictly experimental. The second method uses a numerical experiment together with system identification techniques. The third method is a strictly analytical method, which results in an asymptotically upper bounded estimate of the participating mass. Two risers are examined as case studies. The first riser is a 1 : 100 model scale riser used in collision experiments carried out at Marintek's towing tank in Trondheim, Norway. The second case uses a real world riser in use on the Troll B oil production platform operating in the North Sea. The proposed methods yield consistent and comparable results. Received for publication on Feb. 1, 1999; accepted on July 8, 1999     

现代煤炭港口卸车联合调度优化问题研究

现代煤炭港口由传统装卸服务向综合物流服务转型过程中,对港口整体调度的智能性与效率性要求提升到新高度,因此需要以系统论的观点解决煤炭港口的联合调度优化问题。针对影响卸车调度的关键问题,综合考虑车流集中到达、列车限制性调度等因素,以现代煤炭港口生产工艺流程为基础,重点研究现代煤炭港口卸车联合调度优化,构建以待车时间最短、作业时间最短且关联堆场作业动态的卸车联合调度优化模型(火车-翻车机-堆场联合调度优化模型),运用相应优化策略,分析优化模型,实现卸车调度各环节智能化的最优解决途径。     

Egg production and associated losses of carbon, nitrogen and fatty acids from maternal biomass in Calanus finmarchicus before the spring bloom

We present concurrent data on ingestion, egg production and the loss of maternal biomass in pre-spring bloom female Calanus finmarchicus incubated under conditions representative of those in situ in the North Atlantic. A balanced metabolic budget was constructed and used to examine the relative importance of ingestion and biomass for fuelling egg production during the incubations. Ingested carbon was not sufficient to meet the observed demands for egg production. More than 80% of the carbon utilised by the females was instead derived from their biomass. Fatty acid analysis demonstrated that the storage reserves, 20:1 (n−9) and 22:1 (n−11), were virtually absent before experimentation began, and therefore could not have been used to supply the carbon required for egg production during the incubations. The C:N mass-specific ratio of the biomass utilised was 4.1, suggesting that the females had instead catabolised protein in order to meet their metabolic demands. These results suggest that C. finmarchicus adopts a sacrificial reproductive strategy when food availability is low.     

大功率低速柴油机活塞杆杆身激光淬火应用研究

激光淬火是一种节能、高效、精密的表面淬火技术,采用该技术替代活塞杆加工中传统的表面热处理工艺,研究分析杆身表面硬度分布、硬化层深度变化、表面及几何精度变化等规律,找出符合设计规范的激光表面淬火处理参数,以及活塞杆在制造过程中应用此工艺的可行性。试验研究结果表明：活塞杆激光淬火后表面硬度、有效硬化层深度被大大提高,应用后不需进行应力热处理,减少了加工工序,节约了场地,降低了能耗,减少了污染排放,大大降低了成本。