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This paper researches how to apply the advanced control technology of model predictive control(MPC) to the design of the dynamic positioning system(DPS) of a semi-submersible platform.First,a linear low-frequency motion model with three degrees of freedom was established in the context of a semi-submersible platform.Second,a model predictive controller was designed based on a model which took the constraints of the system into account.Third,simulation was carried out to demonstrate the feasibility of the controller.The results show that the model predictive controller has good performance and good at dealing with the constraints of the system. 相似文献
313.
为了解决冷轧卷板在装卸中的伤残问题,提高装卸效率,研制了新的冷轧卷板装卸工属具。就舱内作业、出舱作业、水平运输作业等装卸工艺提出各种方案,并确定最佳方案,制造相应的工属具。研制的"冷轧卷板水平运输托架"、"冷轧卷板叉车挂胶属具"、"多角度叉车属具"等已获专利,有实用价值。 相似文献
314.
Traffic surveillance is an important topic in intelligent transportation systems (ITS). Robust vehicle detection is one challenging problem for complex traffic surveillance. In this paper, we propose an efficient vehicle detection method by designing vehicle detection grammars and handling partial occlusion. The grammar model is implemented by novel detection grammars, including structure, deformation and pairwise SVM grammars. First, the vehicle is divided into its constitute parts, called semantic parts, which can represent the vehicle effectively. To increase the robustness of part detection, the semantic parts are represented by their detection score maps. The semantic parts are further divided into sub-parts automatically. The two-layer division of the vehicle is modeled into a grammar model. Then, the grammar model is trained by a designed training procedure to get ideal grammar parameters, including appearance models and grammar productions. After that, vehicle detection is executed by a designed detection procedure with respect to the grammar model. Finally, the issue of vehicle occlusion is handled by designing and training specific grammars. The strategy adopted by our method is first to divide the vehicle into the semantic parts and sub-parts, then to train the grammar productions for semantic parts and sub-parts by introducing novel pairwise SVM grammars and finally to detect the vehicle by applying the trained grammars. Experiments in practical urban scenarios are carried out for complex traffic surveillance. It can be shown that our method adapts to partial occlusion and various challenging cases. 相似文献
315.
In contrast to air transport safety, safety in ground handling is not concerned only with aircraft accidents but also the Occupational Health and Safety of the employees who work at airport aprons. Ground handling safety costs the aviation industry tens of billions USD every year which raises the questions about the effectiveness of linear safety risk management of Ground Handling Services (GHS). This paper uses the state-of-the-art safety theory to justify and highlight the need for a systemic approach to safety risk management of GHS on the apron. A hybrid Total Apron Safety Management (TASM) framework, based on the combination of Functional Resonance Analysis Method (FRAM), Grounded Theory, Template Analysis and Goals-Means Task Analysis (GMTA) was developed to support systemic safety modelling of GHS. The data that underpins the TASM framework includes extensive literature review, 15 observations, 43 interviews and expert judgement across five international airports. While the TASM framework can be applied in retrospective, prospective and system design analysis to improve both the safety management and the efficiency of apron operations, this paper showcases only one of its application on a case study of a historical safety occurrence. The results of the investigation carried out in this paper clearly demonstrate the benefits of the systemic as opposed to the existing linear approaches to retrospective safety analyses and the suitability of the TASM framework for occurrence analysis and prevention. 相似文献
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随着跨运车技术的发展,跨运车工艺方式有利于提高码头作业效率的优势得到重视,采用跨运车替代常规的拖挂车和集装箱门式起重机工艺方式中的拖挂车,不但能够提高码头作业效率而且车辆配置的成本降低。 相似文献
318.
为了解决件杂货码头拆装箱作业中存在的难题,有必要开展叉车用装卸吊臂的研制;介绍了叉车用集装内使用的吊臂的设计思路、技术性能和使用性能;并指出了吊臂的应用效果。 相似文献
319.
结合开展码头工程通航环境安全评估的专题研究工作,探讨船舶操纵模拟试验方法在码头工程通航环境安全评估中的应用,该方法主要包括通过船舶操纵模拟器的模拟试验获取的模拟船舶运动参数和运动轨迹,应用航迹带宽度、潜在操船水域、效用函数和靠泊操纵危险度等概念,对拟建码头工程所需的航道宽度、船舶回旋水域和靠泊操纵的安全性进行分析和评判。实际应用表明,该方法能客观、合理地分析与评估码头工程的通航安全,具有较好的应用价值。 相似文献
320.