共查询到18条相似文献，搜索用时 203 毫秒
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集装箱船舶大型化的趋势下,在集装箱码头混合装卸方法的基础上提出了基于堆垛的混合装卸优化方法,并且将一组甲板对应的多贝位集装箱分解为多个单贝位集装箱装卸研究方法模型求解.以最小化单一贝位集装箱装卸的完成时间为目标,建立单贝位数学模型,使用遗传算法求解单贝位的最小完成时间,再根据其和求得一组甲板上、下集装箱装卸的完成时间,并拓展到多组甲板情况.通过数值计算,与传统装卸方法对比分析,验证了模型和算法的可行性和有效性,为大型集装箱船舶装卸方法的优化提供了依据. 相似文献
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集装箱码头是水路和陆路运输的枢纽点,是专供集装箱船舶停靠、装卸集装箱的作业场所,是集装箱货物在转换运输方式时的缓冲地带,也是货物贸易的交接点。集卡是集装箱码头运用最为广泛的装卸运输设备,由于集装箱码头作业流程的复杂性和动态性,码头内存在很多因素影响集卡的作业效率,因此研究集卡的作业效率影响因素,对于提高码头的整体效率,有重要的理论和现实意义。 相似文献
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针对进口铁矿石压港现象十分严重这一情况,从武汉工业港矿石码头的实际出发,提出了对现有工艺流程改造,在堆场规模不变的情况下,提高码头的接卸能力,从而进一步提高武汉工业港码头竞争力。 相似文献
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接地的效果好坏对装卸油品码头的安全生产有着举足轻重的作用,设计、施工、生产过程都要对其加以重视,本文仅从设计方面对装卸油品码头的接地系统作下简要介绍. 相似文献
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随着港口集装箱运输的快速发展,集装箱吊具也不断推陈出新、更新换代,以适应各类港口起重机的应用。门座式起重机也越来越多的使用集装箱吊具进行装卸。其工作速度较快,装卸效率是重要指标。吊具的自动旋转技术则可有效提高门座式起重机的装卸效率。介绍了吊具两种高效率,高精度自动旋转的实现方案,以满足不同的码头更新需求。 相似文献
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太原北车辆段2013年轮轴生产线改造的主体工程--车轴加工流水线建造投产,是全路第一条半龙门轨道机械手运行模式流水线,设计五台车轴机械手完成生产过程中车轴工件的自动输送作业。由于采用伺服系统的空中作业方式,最直接的优点是输送快速准确、传递效率高、工作环境简洁开阔,但另一方面由于是空中输送,机械手上下料定位准确性、运行安全意识丝毫不能松怠。 相似文献
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高峰矿深部由于种种原因,目前只能采用小盲斜井串车提升矿石,靠人工装卸车。而在人工装卸车的过程中,一旦发生飞斗事故,轻则造成设备损伤,重则造成人员伤亡。因此,在高峰矿开展小盲斜井防跑车装置研究,设计适合高峰矿深部小盲斜井防跑车装置,对于保证高峰矿深部开采安全、提高综合开采效益具有重要意义。文章重点研究变坡点下20米的挡车器。 相似文献
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VC++钩子机制在Windows系统中的应用 总被引：1，自引：0，他引：1
本文分析了Windows消息驱动的环境下，钩子机制的概念以及用VC＋＋实现钩子的安装与卸载。最后，用一个获取鼠标信息的完整程序给予说明。 相似文献
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Charles Aguiar Daniel Leite Daniel Pereira Goran Andonovski Igor Škrjanc 《Journal of The Franklin Institute》2021,358(2):1376-1402
Overhead cranes are widely used structures for lifting and conveying heavy loads. The development of feedback control systems for such equipment is important due to the large number of potential applications and advantages over manual operation concerning stability and robustness. This paper aims to represent the key nonlinear dynamics of crane systems by means of a state-space fuzzy model with compact rule-base structure. The fuzzy model is useful to assist the design of a fuzzy controller based on the concept of parallel compensation. A well-posed conservative linear-matrix-inequality (LMI) feasibility problem is formulated so that a solution guarantees closed-loop Lyapunov stability, bounded control inputs, quick positioning of the supporting cart, and suppression of load oscillations and collisions. The fuzzy controller is composed by rules with linear control laws derived from local state-space models. The controller warrants asymptotic convergence of the states. Due to the nonlinear nature of the fuzzy model and controller, Jacobian linearization is avoided. The proposed fuzzy control approach for cranes has shown to be more effective and robust than an optimal quadratic controller, and able to move cargo smoothly and safely to a destination. Particularly, constrained and smoother control inputs avoid actuator saturation, and tend to increase its lifetime. Laboratory experiments using the LMI fuzzy controller and actual data validates the approach for cranes in actual scenario. 相似文献
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选取2002-2010年宁波市港口集装箱吞吐量数据,分别建立灰色预测模型与三次指数平滑模型,在两种模型基础上进行加权组合,建立科学的组合预测模型,并对"十二五"规划期间2011-2015年宁波港集装箱吞吐量进行预测。分析结果表明:组合模型的高精度预测可以对今后一个时期宁波港口发展和改革的战略以及可持续发展的建港提供思路。 相似文献
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本文以茂名电厂300MW机组为例,分析单室平衡容器水位计工作原理与特性。重点说明单室平衡容器水位差压测量方法和补偿系统的建立方法与步骤。就茂名电厂实际情况,分析测量误差的来源,并指出了解决方法。 相似文献
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《Journal of The Franklin Institute》2022,359(12):6099-6122
With the fast development of the economy, marine activities are increasing. Due to the advantages of offshore cranes, they are widely used in marine production as effective transportation tools. As a matter of fact, the offshore crane works on the ship known as a typical noninnertial system, which is affected by the ship movement. To tackle this problem, we propose a time optimal trajectory planning method for the considered offshore crane. Specifically, to tackle the couplings between state variables, we show that the offshore crane system is differentially flat with the payload coordinates as the flat outputs. Based on this fact, the planning problems for the jib motion and the rope length are further converted into the planning problems for flat outputs. Then, in order to ensure the trackability of the planned trajectory and improve the safety, we consider a series of physical constraints including the jib luffing motion velocity and acceleration constraints, the rope length varying velocity and acceleration constraints, and the payload swing angle and angular velocity constraints, and then a time optimization problem is further formulated. By utilizing a bisection-based method, the optimal payload transportation time is obtained as well as the corresponding time optimal trajectories. As far as we know, it is the first time optimal trajectory planning method designed for offshore cranes to achieve the fast and accurate payload transportation as well as the payload swing elimination in earth-fixed frame. At last, the effectiveness of the proposed method is verified by simulation tests. 相似文献