A Methodology to Estimate the Reliability of Passageway system in Naval Ship Design

In this paper, we describe and demonstrate a general methodology to evaluate the reliability of the passageway system in warship design. The reliability of the passageway system is the most important component of naval ship survivability evaluation. Currently, most of the passageway evaluations focus on human factor or physical distribution; integrated calculates is lacking to estimate the reliability of the passageway system. The challenge for naval architects is to develop a systematic methodology that allows accurate evaluation of the passageway reliability associated with crews movement and related material operating procedure. The paper consults the concept of network reliability and lays out an evaluation method of passageway system based on task reliability. The method integrated analyses the impact of ship crew‘s location and distribution of the shipborne material. As it was difficult to achieve the reality data, the methodology is demonstrated using a hypothetical warship combining with the simulation software on the basis of two different evaluation scenarios.

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THE IMPACT OF SUBSYSTEMS ON NAVAL SHIP DESIGN

Naval Engineers Journal ◽

10.1111/j.1559-3584.1975.tb03781.x ◽

1975 ◽

Vol 87 (6) ◽

pp. 15-25 ◽

Cited By ~ 6

Author(s):

CLARK GRAHAM

Keyword(s):

Ship Design ◽

Naval Ship ◽

The Impact

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A systematic methodology to assess the impact of human factors in ship design

Applied Mathematical Modelling ◽

10.1016/j.apm.2007.12.014 ◽

2009 ◽

Vol 33 (2) ◽

pp. 867-883 ◽

Cited By ~ 15

Author(s):

S.J. Deere ◽

E.R. Galea ◽

P.J. Lawrence

Keyword(s):

Human Factors ◽

Ship Design ◽

Systematic Methodology ◽

The Impact

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Design Structure Matrix (DSM) Methods and Applications for Naval Ship Design

10.21236/ada587357 ◽

2013 ◽

Author(s):

Tyson R. Browning

Keyword(s):

Ship Design ◽

Design Structure Matrix ◽

Structure Matrix ◽

Design Structure ◽

Naval Ship

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Experimental and Numerical Study of Fracture Behavior of Rock-Like Material Specimens with Single Pre-Set Joint under Dynamic Loading

Materials ◽

10.3390/ma14102690 ◽

2021 ◽

Vol 14 (10) ◽

pp. 2690

Author(s):

Bo Pan ◽

Xuguang Wang ◽

Zhenyang Xu ◽

Lianjun Guo ◽

Xuesong Wang

Keyword(s):

Crack Initiation ◽

Crack Propagation ◽

Joint Angle ◽

Simulation Software ◽

Dissipated Energy ◽

Energy Structure ◽

Joint Angles ◽

Crack Penetration ◽

Before And After ◽

The Impact

The Split Hopkinson Pressure Bar (SHPB) is an apparatus for testing the dynamic stress-strain response of the cement mortar specimen with pre-set joints at different angles to explore the influence of joint attitudes of underground rock engineering on the failure characteristics of rock mass structure. The nuclear magnetic resonance (NMR) has also been used to measure the pore distribution and internal cracks of the specimen before and after the testing. In combination with numerical analysis, the paper systematically discusses the influence of joint angles on the failure mode of rock-like materials from three aspects of energy dissipation, microscopic damage, and stress field characteristics. The result indicates that the impact energy structure of the SHPB is greatly affected by the pre-set joint angle of the specimen. With the joint angle increasing, the proportion of reflected energy moves in fluctuation, while the ratio of transmitted energy to dissipated energy varies from one to the other. NMR analysis reveals the structural variation of the pores in those cement specimens before and after the impact. Crack propagation direction is correlated with pre-set joint angles of the specimens. With the increase of the pre-set joint angles, the crack initiation angle decreases gradually. When the joint angles are around 30°–75°, the specimens develop obvious cracks. The crushing process of the specimens is simulated by LS-DYNA software. It is concluded that the stresses at the crack initiation time are concentrated between 20 and 40 MPa. The instantaneous stress curve first increases and then decreases with crack propagation, peaking at different times under various joint angles; but most of them occur when the crack penetration ratio reaches 80–90%. With the increment of joint angles in specimens through the simulation software, the changing trend of peak stress is consistent with the test results.

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A simplified iterative approach for testing the pulse derailment of light rail vehicles across a viaduct to near-fault earthquake scenarios

Proceedings of the Institution of Mechanical Engineers Part F Journal of Rail and Rapid Transit ◽

10.1177/0954409720987410 ◽

2021 ◽

pp. 095440972098741

Author(s):

Ling-Kun Chen ◽

Peng Liu ◽

Li-Ming Zhu ◽

Jing-Bo Ding ◽

Yu-Lin Feng ◽

...

Keyword(s):

Ground Motions ◽

Simulation Software ◽

Light Rail ◽

Rail Transit ◽

Light Rail Transit ◽

Seismic Responses ◽

Near Fault ◽

Rail Vehicle ◽

Pulse Type ◽

The Impact

Near-fault (NF) earthquakes cause severe bridge damage, particularly urban bridges subjected to light rail transit (LRT), which could affect the safety of the light rail transit vehicle (“light rail vehicle” or “LRV” for short). Now when a variety of studies on the fault fracture effect on the working protection of LRVs are available for the study of cars subjected to far-reaching soil motion (FFGMs), further examination is appropriate. For the first time, this paper introduced the LRV derailment mechanism caused by pulse-type near-fault ground motions (NFGMs), suggesting the concept of pulse derailment. The effects of near-fault ground motions (NFGMs) are included in an available numerical process developed for the LRV analysis of the VBI system. A simplified iterative algorithm is proposed to assess the stability and nonlinear seismic response of an LRV-reinforced concrete (RC) viaduct (LRVBRCV) system to a long-period NFGMs using the dynamic substructure method (DSM). Furthermore, a computer simulation software was developed to compute the nonlinear seismic responses of the VBI system to pulse-type NFGMs, non-pulse-type NFGMs, and FFGMs named Dynamic Interaction Analysis for Light-Rail-Vehicle Bridge System (DIALRVBS). The nonlinear bridge seismic reaction determines the impact of pulses on lateral peak earth acceleration (Ap) and lateral peak land (Vp) ratios. The analysis results quantify the effects of pulse-type NFGMs seismic responses on the LRV operations' safety. In contrast with the pulse-type non-pulse NFGMs and FFGMs, this article's research shows that pulse-type NFGM derail trains primarily via the transverse velocity pulse effect. Hence, this study's results and the proposed method can improve the LRT bridges' seismic designs.

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Research on Reliability Evaluation Methods of Distribution System

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.672-674.1441 ◽

2014 ◽

Vol 672-674 ◽

pp. 1441-1446 ◽

Cited By ~ 1

Author(s):

Yu Qiang Ou ◽

Le Feng Cheng ◽

Jian Zhong Wen ◽

Xuan Yu Qiu ◽

Tao Yu

Keyword(s):

Distribution System ◽

Evaluation Method ◽

Network Reliability ◽

Distribution Network ◽

Reliability Evaluation ◽

Evaluation Indexes ◽

Specific Distribution ◽

And Function ◽

Meaning And Function

Research on reliability of distribution network has very important meaning and function to ensure the quality of power supply. This paper introduces some basic concepts of reliability in distribution network, including distribution network reliability definition, task and index. The classical reliability evaluation method was reviewed, and focused on specific distribution network, an example analysis was given, and specific reliability evaluation indexes were calculated. Finally, the future development of distribution network reliability evaluation was made a simple prospect.

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Coupling building energy simulation software with microclimatic simulation for the evaluation of the impact of urban outdoor conditions on the energy consumption and indoor environmental quality

Energy and Buildings ◽

10.1016/j.enbuild.2017.02.020 ◽

2017 ◽

Vol 157 ◽

pp. 101-115 ◽

Cited By ~ 16

Author(s):

Kostantinos Gobakis ◽

Dionysia Kolokotsa

Keyword(s):

Energy Consumption ◽

Environmental Quality ◽

Building Energy ◽

Simulation Software ◽

Energy Simulation ◽

Building Energy Simulation ◽

Indoor Environmental Quality ◽

Microclimatic Simulation ◽

The Impact

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Assessment of the Construction of a Climate Resilient City: An Empirical Study Based on the Difference in Differences Model

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18042082 ◽

2021 ◽

Vol 18 (4) ◽

pp. 2082

Author(s):

Zifeng Liang

Keyword(s):

Significant Contribution ◽

Evaluation Method ◽

Regional Climate ◽

Chinese Government ◽

Infrastructure Development ◽

Grey System ◽

Difference In Differences ◽

Climate Resilience ◽

The Difference ◽

The Impact

Facing climate risks has become a common problem for mankind and a topic of great importance for the Chinese government. To thoroughly implement the overall requirements for the construction of an ecological civilization and effectively improve the capacity of cities to adapt to climate change, China launched the pilot construction of “Climate Resilient Cities” in 2017. In this paper, 16 prefecture level cities in Anhui Province of China were selected as the research objects, and the multi-level grey system evaluation method was used to measure the climate resilience of these regions. We used the difference in differences method to evaluate the effect of the pilot policy of “Climate Resilient Cities.” The pilot policies of the “Climate Resilient Cities” showed a significant contribution to the regional climate resilience, and, after isolating the impact of other factors on the regional climate resilience, the pilot policies of the “Climate Resilient Cities” increased the climate resilience of the pilot cities by four percentage points. The pilot policies of the “Climate Resilient Cities” had a significant contribution to the urban infrastructure development and ecological space optimization, as well as non-significant impacts to the urban water security, emergency management capacity-building, and science and technology innovation initiatives.

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Design and simulation analysis of impact-resistant flexible drill pipe for rock-breaking rig

Noise & Vibration Worldwide ◽

10.1177/09574565211030707 ◽

2021 ◽

pp. 095745652110307

Author(s):

Kangping Gao ◽

Xinxin Xu ◽

Ning Shi ◽

Shengjie Jiao

Keyword(s):

Impact Force ◽

Drill Pipe ◽

Rock Breaking ◽

Control Model ◽

Simulation Software ◽

System Stability ◽

Series Elastic Actuator ◽

Pipe Model ◽

The Impact ◽

Series Elastic

In the process of drilling and coring by the rock-breaking rig, the drill rod is affected by the intermittent impact force, which reduces the efficiency of the rig to break the rock and increases the cost of the drilling and coring. Therefore, it is very important to improve the impact resistance of the drill pipe during the rock-breaking process. To achieve this goal, a flexible design of the drill pipe was carried out, and a dynamical model of the drilling rig based on a series elastic actuator was established. Considering the dynamic performance of the system, a torque feedforward link is introduced and a control model based on the force source is established. The influence of the equivalent inertia of the transmission system and the series elastic actuator damping coefficient on the system stability was analyzed by drawing the frequency domain characteristic curve of the system. By using the control and Simulink simulation software, the electromechanical simulation of the model is carried out, and the torque step tracking response of the system is obtained. A torque feedforward link is introduced to establish the control model of the system based on force source. Through dynamic simulation software ADAMS, dynamic and static impact simulation experiments were carried out on the system. The results show that when a force of 200 N is applied to the output end of the drill pipe in the tangential direction, the maximum moments received by the joint under static and dynamic environments are 34.1 N·m and 57.9 N·m, respectively. When the impact force disappears, the time required for the flexible drill pipe to reach a stable state is only 0.15 s, which verifies that the series elastic actuator–based drill pipe model can alleviate the impact of the external environment and protect the internal structure of the rig.

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