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991.
利用Ansys进行网架结构损伤诊断的数值模拟研究 总被引:1,自引:0,他引:1
利用结构动力参数的改变对空间钢网架进行损伤分析,其中许多指标对损伤并不敏感.文中通过结构有限元分析软件ANSYS得到网架结构位移模态分析数据,采用杆件轴向应变变化率的模态分析技术针对不同损伤状况的钢结构网架进行损伤识别,能够较为准确地诊断出网架杆件的损伤位置. 相似文献
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A novel intelligent drug delivery system potential for the more effective therapy of the diabeticswas proposed, and the composition of system was analyzed. Based on the design of micro-electro-mechanicalsystems (MEMS), an iterative modeling process was introduced. Unified modeling language (UML) was em-ployed to describe the function requirement, and different diagrams were built up to explore the static model,the dynamic model and the employment model. The mapping analysis of different diagrams can simply verifythe consistency and completeness of the system model. 相似文献
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[Objectives]In order to give full play to role of "operational concepts" in the engineering process of military equipment development, it is necessary to understand and form standardized operational concept documents (OCD), and study the modeling design of OCD in order to implement the transformation of the system engineering process from document-centric to model-centric. [Methods]This study analyzes the US military's definition of operational concepts and introduces its hierarchical operational concepts, especially the bottom level ConOps or OpsCon, usually as a part of equipment acquisition and requirement engineering. Lessons are then drawn from the relevant theories and standards such as IEEE 29148:2018 and ANSI/AIAA G-043B-2018 of the operational concepts document outline in order to design the specifications of the OCD. Finally, key technologies are studied, including SysML-based OpsCon modeling, UML Profile-based OpsCon framework design and MSDL/C-BML-based operational scenario development.[Result]The results indicate the effectiveness of implementing the modeling design of OCDs. [Conclusions]In the process of equipment requirement engineering, the results of this study can help to improve the efficiency of equipment requirement demonstration through an ambiguous operational concept model and an engineering environment for all stakeholders of the system. © 2022 Journal of Clinical Hepatology. All rights reserved. 相似文献
998.
在分析世界范围内主要城市群市郊铁路与地铁衔接方式的基础上,从线网衔接角度,研究中心区终止与外围区接入2种模式的主要特征及适应性;从运营组织衔接角度,研究换乘与直通衔接2种模式的主要特征及适应性。结合北京市郊铁路网规划和建设情况,指出了北京市郊铁路与地铁衔接的不同模式。 相似文献
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In 2006, a review of maritime accidents found that non-technical skills (NTSs) are the single largest contributing factor towards such incidents. NTSs are composed of both interpersonal and cognitive elements. These include things such as situational awareness, teamwork, decision making, leadership, management and communication skills. In a crisis situation, good NTSs allow a deck officer to quickly recognise that a problem exists and then harness the resources that are at their disposal to safely and efficiently bring the situation back under control. This paper has two aims. The first is to develop a methodology which will enable educators to quantitatively assess the impact of Maritime and Coastguard Agency (MCA)-approved Human Element, Leadership and Management (HELM) training on deck officer’s NTSs with a view to identifying further training requirements. The second is to determine whether the HELM training provided to develop the NTSs of trainee deck officers is fit for purpose. To achieve these aims, a three-phase approach was adopted. Initially, a taxonomy for deck officer’s NTSs is established, behavioural markers are identified and the relative importance of each attribute is calculated using the analytical hierarchy process (AHP). Subsequently, a set of scenarios were identified for the assessment of deck officer’s NTSs in a ship bridge simulator environment. A random selection of students that have completed the Chief Mate (CM) programme was performed, and data regarding their NTS-related performance in the scenarios was collected. Finally, the collected data was fed into the evidential reasoning (ER) algorithm, utility values were produced and, having established these values, the effectiveness of the HELM training that the students have received was then evaluated. 相似文献
1000.
Thomas A. Hamade 《上海交通大学学报(英文版)》2018,23(1):112-121
A novel high-voltage electrostatics corona ions pre-charger apparatus and methods were invented earlier by Hamade related to treat various types of receptors such as but not limited to electret polymer, air filters, particulates, catalytic converters, bioaerosols, fluids, pollutants, virus, and bacteria. It is shown in this article that his work led to the construction of various prototype chargers, customized differently for each type of a receptor. In particular his recent development of biological matter corona charger (BMCC) prototype related to expose, treat, sanitize, and disinfect bioaerosols, virus, bacteria, and contaminated fluids and blood such as human immunodeficiency virus (HIV) - acquired immune deficiency syndrome (AIDS). It is shown in this paper that each previous investigated research contemplated ionized corona charger attendant to a charging process and the corona, imparts and provides enough treatment charges to receptors including the aforementioned receptors. Researchers often relied on adopting prior corona charger methods that do not necessarily and effectively solve the problems associated with them or utilize them for optimum treatment effect. The inventor exhaustively studied the characteristics of corona discharge, and has found that the greatest difficulty in corona discharge has to do with the maintenance of the corona, particularly when the receptor is being charged. This is due to variations in either the dielectric value between the corona electrode and a grounded base or flaws in the design as the receptor passes there between suppressing or hindering corona and its effectiveness. What is needed in-the-art is an apparatus and method to achieve maximum possible charge on a receptor, a charge order of magnitude greater than that used by other investigators. This often requires customizing each apparatus and method and does not just merely use one type of a charger to satisfy all applications. To satisfy this need, we build a low cost prototype BMCC that generates self-sustaining charge corona, eliminates many previous design flaws such as spark over, and make it ready for testing remotely or with apparatus. 相似文献