Exact Reliability for a Multi-State Consecutive Linear (Circular) k-out-of-r-from-n:F System

2020 ◽  
pp. 2150014
Author(s):  
Y. Amirian ◽  
A. Khodadadi
Keyword(s):  
Closed Form ◽  
Real World ◽  
Numerical Results ◽  
State Probability ◽  
Complete Failure ◽  
State Models ◽  
First Time ◽  
Exact Amount

The multi-state consecutive linear (circular) [Formula: see text]-out-of-[Formula: see text]-from-[Formula: see text] system consists of [Formula: see text] linear (circular) ordered multi-state components. Both the system and its components can have [Formula: see text] different states: from complete failure (zero state) up to perfect functioning (([Formula: see text]1) state). In this paper we suggest, for the first time, exact reliability for these models. The system is at state below [Formula: see text] if and only if at least [Formula: see text] components out of any [Formula: see text] consecutive are in state below [Formula: see text] [Formula: see text]. Recent efforts in these branches have focused on simple situations or approximation bands for their reliability in two-state or multi-state models but closed form and exact amount not gained. In the continuation, there are the matlab programs of linear (circular) reliability system and [Formula: see text] state probability for [Formula: see text] in system. In the following, we applied comparative and numerical results and calculated the exact reliability of this strategic systems. Finally, we calculated the exact reliability for two real-world practical examples.

Exact Reliability for a Consecutive Circular k-out-of-r-from-n: F System with Equal and Unequal Component Probabilities

2019 ◽  
Vol 27 (01) ◽  
pp. 2050003 ◽  
Author(s):  
Y. Amirian ◽  
A. Khodadadi ◽  
O. Chatrabgoun
Keyword(s):  
Closed Form ◽  
Reliability Analysis ◽  
Numerical Results ◽  
Innovative Program ◽  
Circular Component ◽  
Extensive Class ◽  
Exact Amount ◽  
F System

A consecutive linear (circular) [Formula: see text]-out-of-[Formula: see text]-from-[Formula: see text]: F system consists of [Formula: see text] linear (circular)-ordered components such that the system fails if and only if there exists a set of [Formula: see text] consecutive linear (circular) component that contains at least [Formula: see text] failed components. Consecutive linear (circular) [Formula: see text]-out-of-[Formula: see text]-from-[Formula: see text]: F systems attract tremendous attention for researchers of reliability analysis. Recent efforts in this area have focused on simple situations or approximation bands for their reliability but closed form and exact amount not gained. In this paper, we designed an innovative algorithm and an innovative program to obtain the exact reliability for an extensive class of consecutive circular [Formula: see text]-out-of-[Formula: see text]-from-[Formula: see text]: F system with particular emphasis for equal and unequal component probabilities. Finally, we reviewed an applied example and applied comparative and numerical results and calculated the exact reliability of this strategic system.

scholarly journals How to evaluate sustainability of supply chains? A dynamic network DEA approach

2017 ◽  
Vol 117 (9) ◽  
pp. 1866-1889 ◽  
Author(s):  
Vahid Shokri Kahi ◽  
Saeed Yousefi ◽  
Hadi Shabanpour ◽  
Reza Farzipoor Saen
Keyword(s):  
Big Data ◽  
Supply Chains ◽  
Real World ◽  
Performance Optimization ◽  
Network Dynamic ◽  
Network Dea ◽  
Content Type ◽  
Dea Model ◽  
Proposed Model ◽  
First Time

Purpose The purpose of this paper is to develop a novel network and dynamic data envelopment analysis (DEA) model for evaluating sustainability of supply chains. In the proposed model, all links can be considered in calculation of efficiency score. Design/methodology/approach A dynamic DEA model to evaluate sustainable supply chains in which networks have series structure is proposed. Nature of free links is defined and subsequently applied in calculating relative efficiency of supply chains. An additive network DEA model is developed to evaluate sustainability of supply chains in several periods. A case study demonstrates applicability of proposed approach. Findings This paper assists managers to identify inefficient supply chains and take proper remedial actions for performance optimization. Besides, overall efficiency scores of supply chains have less fluctuation. By utilizing the proposed model and determining dual-role factors, managers can plan their supply chains properly and more accurately. Research limitations/implications In real world, managers face with big data. Therefore, we need to develop an approach to deal with big data. Practical implications The proposed model offers useful managerial implications along with means for managers to monitor and measure efficiency of their production processes. The proposed model can be applied in real world problems in which decision makers are faced with multi-stage processes such as supply chains, production systems, etc. Originality/value For the first time, the authors present additive model of network-dynamic DEA. For the first time, the authors outline the links in a way that carry-overs of networks are connected in different periods and not in different stages.

scholarly journals Efficacy of BRAF and MEK Inhibition in Patients with BRAF-Mutant Advanced Melanoma and Germline CDKN2A Pathogenic Variants

Cancers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 2440
Author(s):  
Francesco Spagnolo ◽  
Bruna Dalmasso ◽  
Enrica Tanda ◽  
Miriam Potrony ◽  
Susana Puig ◽  
...  
Keyword(s):  
Real World ◽  
Response Rate ◽  
Suppressor Gene ◽  
Phase Iii ◽  
Clinical Activity ◽  
P Value ◽  
Pathogenic Variants ◽  
Phase Iii Trials ◽  
The Difference ◽  
First Time

Inherited pathogenic variants (PVs) in the CDKN2A tumor suppressor gene are among the strongest risk factors for cutaneous melanoma. Dysregulation of the p16/RB1 pathway may intrinsically limit the activity of MAPK-directed therapy due to the interplay between the two pathways. In our study, we assessed, for the first time, whether patients with germline CDKN2A PVs achieve suboptimal results with BRAF inhibitors (BRAFi)+/−MEK inhibitors (MEKi). We compared the response rate of nineteen CDKN2A PVs carriers who received first-line treatment with BRAFi+/−MEKi with an expected rate derived from phase III trials and “real-world” studies. We observed partial response in 16/19 patients (84%), and no complete responses. The overall response rate was higher than that expected from phase III trials (66%), although not statistically significant (p-value = 0.143; 95% CI = 0.60–0.97); the difference was statistically significant (p-value = 0.019; 95% CI = 0.62–0.97) in the comparison with real-world studies (57%). The clinical activity of BRAFi+/−MEKi in patients with germline CDKN2A PV was not inferior to that of clinical trials and real-world studies, which is of primary importance for clinical management and genetic counseling of this subgroup of patients.

scholarly journals FIRST DIGIT DISTRIBUTION OF HADRON FULL WIDTH

2009 ◽  
Vol 24 (40) ◽  
pp. 3275-3282 ◽  
Author(s):  
LIJING SHAO ◽  
BO-QIANG MA
Keyword(s):  
Real World ◽  
Particle Physics ◽  
Benford’S Law ◽  
Full Width ◽  
Scale Invariant ◽  
Benford's Law ◽  
Science Domain ◽  
Logarithmic Distribution ◽  
First Time ◽  
Power Invariant

A phenomenological law, called Benford's law, states that the occurrence of the first digit, i.e. 1, 2,…, 9, of numbers from many real world sources is not uniformly distributed, but instead favors smaller ones according to a logarithmic distribution. We investigate, for the first time, the first digit distribution of the full widths of mesons and baryons in the well-defined science domain of particle physics systematically, and find that they agree excellently with the Benford distribution. We also discuss several general properties of Benford's law, i.e. the law is scale-invariant, base-invariant and power-invariant. This means that the lifetimes of hadrons also follow Benford's law.

scholarly journals A Closed-Form Buckling Formula for Open-Coiled and Properly Supported Circular-Bar Helical Springs

2018 ◽  
Vol 68 (3) ◽  
pp. 33-48
Author(s):  
Yildirim Vebil
Keyword(s):  
Closed Form ◽  
Elementary Theory ◽  
Circular Section ◽  
Helical Springs ◽  
Helix Pitch ◽  
Wide Range ◽  
The Mean ◽  
Artificial Neural Network Ann ◽  
Circular Bar ◽  
First Time

AbstractAs a continuation of the author’s previous studies on the buckling analysis of helical springs, a closed-form formula having been obtained with the help of the artificial neural network (ANN) is proposed and discussed in detail for the first time for a cylindrical close/open-coiled helical spring with fixed ends and having a solid circular section. As far as the author knows there is no such a formula in the open-literature to consider the effects of all stress resultants (torsional and bending moments, axial and shearing forces), large helix pitch angles together with the axial and shear deformations on the buckled state. The present formula may be used in a wide range of the total number of active turns, the ratio of the free axial length to the mean helix diameter, and the spring index. It is yet again revealed that it is not appropriate to use the elementary theory to determine the critical buckling loads for open-coiled springs. The present formula may allow the deeper understanding of spring buckling mechanism and to be used directly and safely in the design processes of such closely/open-coiled springs.

A Closed-Form Solution for Selecting Maximum Critically Damped Actuator Impedance Parameters

2014 ◽  
Vol 137 (4) ◽  
Author(s):  
Nicholas Paine ◽  
Luis Sentis
Keyword(s):  
Closed Form ◽  
Parameter Space ◽  
Real World ◽  
Closed Form Solution ◽  
System Stability ◽  
Limiting Factors ◽  
Closed Form Expression ◽  
Phase Margin ◽  
Form Expression ◽  
Feedback Parameter

This paper introduces a simple and effective method for selecting the maximum feedback gains in PD-type controllers applied to actuators where feedback delay and derivative signal filtering are present. The method provides the maximum feedback parameters that satisfy a phase margin criteria, producing a closed-loop system with high stability and a dynamic response with near-minimum settling time. Our approach is unique in that it simultaneously possesses: (1) a model of real-world performance-limiting factors (i.e., filtering and delay), (2) the ability to meet performance and stability criteria, and (3) the simplicity of a single closed-form expression. A central focus of our approach is the characterization of system stability through exhaustive searches of the feedback parameter space. Using this search-based method, we locate a set of maximum feedback parameters based on a phase margin criteria. We then fit continuous equations to this data and obtain a closed-form expression which matches the sampled data to within 2–4% error for the majority of the parameter space. We apply our feedback parameter selection method to two real-world actuators with widely differing system properties and show that our method successfully produces the maximum achievable nonoscillating impedance response.

scholarly journals Delay chemical master equation: direct and closed-form solutions

2015 ◽  
Vol 471 (2179) ◽  
pp. 20150049 ◽  
Author(s):  
Andre Leier ◽  
Tatiana T. Marquez-Lago
Keyword(s):  
Master Equation ◽  
Closed Form ◽  
Stochastic Simulation Algorithm ◽  
Chemical Master Equation ◽  
Kolmogorov Equation ◽  
Closed Form Solutions ◽  
Mrna Maturation ◽  
First Time ◽  
Nonlinear Markov Process ◽  
Reaction Schemes

The stochastic simulation algorithm (SSA) describes the time evolution of a discrete nonlinear Markov process. This stochastic process has a probability density function that is the solution of a differential equation, commonly known as the chemical master equation (CME) or forward-Kolmogorov equation. In the same way that the CME gives rise to the SSA, and trajectories of the latter are exact with respect to the former, trajectories obtained from a delay SSA are exact representations of the underlying delay CME (DCME). However, in contrast to the CME, no closed-form solutions have so far been derived for any kind of DCME. In this paper, we describe for the first time direct and closed solutions of the DCME for simple reaction schemes, such as a single-delayed unimolecular reaction as well as chemical reactions for transcription and translation with delayed mRNA maturation. We also discuss the conditions that have to be met such that such solutions can be derived.

scholarly journals Displaying Red and Black on a First Date: A Field Study Using the “First Dates” Television Series

2018 ◽  
Vol 16 (2) ◽  
pp. 147470491876941 ◽  
Author(s):  
Robin S. S. Kramer ◽  
Jerrica Mulgrew
Keyword(s):  
Field Study ◽  
Real World ◽  
Television Series ◽  
Men And Women ◽  
First Time

Previous research has shown that displaying the color red can increase attractiveness. As a result, women display red more often when expecting to meet more attractive men in a laboratory context. Here, we carried out a field study by analyzing 546 daters from the “First Dates” television series. Each participant was filmed in a pre-date interview and during a real first date, allowing direct comparison of the clothing worn by each person in these two contexts. Analysis of ratings of the amount of red displayed showed that both men and women wore more red clothing during their dates. This pattern was even stronger for black clothing, while the amount of blue clothing did not differ across the two contexts. Our results provide the first real-world demonstration that people display more red and black clothing when meeting a possible mate for the first time, perhaps seeking to increase their attractiveness and/or reveal their intentions to potential partners.

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