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1

A Study on the Significance of the Design Parameters of Steel Plate Shear Walls Subjected to Monotonic Loading

Honarmand Saeed, Homami Peyman, Gharehbaghi Vahidreza, Noroozinejad Farsangi Ehsan

Civil and Environmental Engineering Reports

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2020

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Vol. 30, no. 4

142--154

EN

Steel plate shear walls (SPSWs) as a resistant system against lateral loads have a high potential for earthquake energy dissipation. Due to the uncertainties of loading, construction, and installation of SPSWs, it is vital to investigate the importance of each component and achieve higher accuracy in design and the implementation of these members. In this paper, a sensitivity analysis is carried out to determine the significance of important uncertainties. The results denoted that the most important parameters affecting the loading capacity of the SPSWs are height, thickness, length, Young's modulus of the wall material, flange, and web thickness of the column, respectively.

2

Simulation of Reliability Prediction Based on Multiple Factors for Spinning Machine

Li Chen, Liu Rongxing, Pan Fukui

Autex Research Journal

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2020

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Vol. 20, no. 1

17--23

EN

Reliability prediction of spinning machines can result in a time-saving and cost-saving development process with high reliability. Based on an analysis of failure times among systems and subsystems, a simulation method for reliability prediction of spinning machines is proposed by using the Monte Carlo simulation model. Firstly, factor weights are determined according to the fuzzy scoring and analytic hierarchy process. According to the status of reliability growth, growth coefficients are proposed based on reliability influencing factor weights and fuzzy scoring. To achieve the prediction of reliability distribution law, reliability index, and fault frequency, the reliability prediction model is constituted by combining the reliability growth coefficient and the Monte Carlo simulation model. Simulation results for spinning machines are obtained via the model thus built, which are confirmed with a practical example.

3

Reliability model of sequence motions and its solving idea

Sun Yao, Sun Zhili, Yin Mingang, Zhou Jie

Eksploatacja i Niezawodność

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2019

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Vol. 21, no. 3

359--366

EN

The missions of weapon systems are becoming increasingly complex. Thus, more mechanism motions than one are required to complete one mission. Under such conditions, a sort of mission has emerged, that needs a few mechanism motions to be executed in sequence. This means that the mission is not completed until all the motions have been executed successfully in strict sequence. This sequence motion system can be considered as a traditional series system with the motions treated as subsystems. Then, the system reliability can be analyzed with the traditional series system reliability method. However, this method cannot fully reflect the characteristics of a sequence. In this work, a reliability model of sequence motions and its solving idea are proposed. In this reliability model, the influence factors of each motion are included. Particularly, the performance function of the former motion is regarded as just one of the influence factors of the next motion, which is the most significant feature for the sequence motion system. Afterward, a solving idea with characteristics of a gradually shrinking sample space is proposed based on Monte-Carlo simulation. Finally, the reliability model of sequence motions and its solving idea are illustrated with a case study on the automatic chain shell magazine sequence motions of a self-propelled artillery.

PL

Misje systemów uzbrojenia stają się coraz bardziej złożone. Często, jedna misja wymaga wykonania przez układ zmechanizowany więcej niż jednego ruchu. W artykule omówiono misję, w której układ zmechanizowany wykonuje sekwencję kilku ruchów. Misja w takim układzie nie zostanie ukończona, dopóki wszystkie ruchy nie zostaną prawidłowo wykonane w ściśle określonej kolejności. Taki układ sekwencyjnych ruchów można rozważać w kategoriach tradycyjnego systemu szeregowego, traktując poszczególne ruchy jako jego podsystemy. Wówczas, niezawodność systemu można analizować za pomocą tradycyjnej metody analizy niezawodności systemów szeregowych. Jednak, metoda ta nie jest w stanie w pełni odzwierciedlić charakterystyki sekwencji. W niniejszym artykule zaproponowano model niezawodności ruchów sekwencyjnych oraz jego rozwiązanie.

4

Critical Condition of Sewage Network

Raganowicz A.

Geomatics and Environmental Engineering

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2018

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Vol. 12, no. 1

91--108

PL

W artykule przedstawiono metodykę modelowania statystyczno-stochastycznego krytycznego stanu technicznego sieci kanalizacyjnej. Stan krytyczny badanego obiektu zdfiniowano jako przejście przewodów kanalizacyjnych od stanu konserwycji do stanu rehabilitacji technicznej. Badania modelowe obejmują kolektory betonowe DN 600/1100, DN 800/1200, DN 900/1350 mm, przewody kamionkowe DN 200–400 mm i przyłącza kamionkowe DN 100-200 mm. Modelowanie statystyczne oparto na rozkładzie Weibulla, a estymację jego parametrów na metodzie momentów. Natomiast modelowanie stochastyczne przeprowadzono na podstawie kombinacji rozkładu Weibulla z metodą Monte-Carlo. Ustalenie krytcznego stanu pozwala na szczegółową ocenę techniczną badanej sieci kanalizacyjnej.

EN

The paper presents the methodology formulated for determining the critical technical state of operating sewer pipes that is based on statistical-stochastic modeling. It describes the theoretical boundary between the area comprised of pipes that do not show any damage or require only maintenance measures and the area comprised of pipes that require renovation. The study includes concrete collectors with dimensions of DN 600/1100, 800/1200, and 900/1350 mm, stoneware pipes of with diameters ranging from DN 200 mm to 400 mm, and stoneware connections (DN 100–200 mm). The statistical modeling phase was carried out using Weibull distribution, and its parameters were evaluated by the method of moments. In contrast, the stochastic studies were based on a combination of the method of moments and Monte-Carlo mathematical simulations. On the basis of the proposed forecasting, it was possible to carry out a qualitative and quantitative analysis of the technical condition of the exploited sewage systems. Quantitative analysis helped us to determine the necessary range of renovation, which is an important operation component of every linear sewage network.

5

Dependability of discrete transport system : model, simulation, measures

Mazurkiewicz J.

Journal of Polish Safety and Reliability Association

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2011

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Vol. 2, No. 1

143--152

EN

The paper proposes a method of reliability and functional analysis related to discrete transport systems. The proposed analysis is based on modelling and simulating of the system behaviour. Monte Carlo simulation is used for proper reliability and functional parameters calculation. The simulator is built using Scalable Simulation Framework (SSF). No restriction on the system structure and on a kind of distribution is the main advantage of the method. The paper presents some exemplar system modelling. The authors stress the problem of influence of the reliability parameters for final functional measures (required time of delivery) – the key value to calculate the availability of the system. They also propose to measure the economic quality of discrete transport system by “profit function”. The presented problem is practically essential for defining an organization of vehicle maintenance and transportation system logistics.

6

Critical situations and human resources in discrete transportation systems analysis

Walkowiak T., Mazurkiewicz J.

Journal of Polish Safety and Reliability Association

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2011

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Vol. 2, No. 1

205--216

EN

The paper presents an approach to critical situations analysis related to discrete transportation systems (DTS). The critical situation is understood as sudden shortage of some system recourses resulting in the transportation system performance degradation. The analysis is realized based on availability calculation of DTS. The system is described by the formal model, which includes reliability and functional parameters of DTS as well as human resources – drivers and management system. The availability and average availability of the system, defined in a functional way, is discussed as a function of different essential parameters of DTS. The proposed analysis is based on the modelling and simulating of the system behaviour using Monte-Carlo approach. The paper presents some exemplar systems – based on real Polish Post DTS – modelling and results.