LONG-RUN AVAILABILITY OF A ROBOT-SAFETY DEVICE SYSTEM

2000 ◽  
Vol 07 (02) ◽  
pp. 169-175 ◽  
Author(s):  
E. J. VANDERPERRE ◽  
S. S. MAKHANOV
Keyword(s):  
Entire System ◽  
Safety Device ◽  
Kolmogorov Type ◽  
Numerical Examples ◽  
Robot Safety ◽  
Natural Feature ◽  
Long Run ◽  
Random Behavior ◽  
Fast Repair ◽  
Repair Facility

We consider a robot-safety device system attended by two different repairmen. The system is characterized by the natural feature of cold standby and by an admissible "risky" state. In order to describe the random behavior of the entire system (robot, safety device, repair facility) we introduce a stochastic process endowed with probability kernels satisfying general Kolmogorov-type equations. Next, we derive the long-run availability of the robot-safety system. Some numerical examples are provided. Finally, as an application, we consider the particular but important case of fast repair.

RISK ANALYSIS OF A ROBOT-SAFETY DEVICE SYSTEM

2002 ◽  
Vol 09 (01) ◽  
pp. 79-87 ◽  
Author(s):  
E. J. VANDERPERRE ◽  
S. S. MAKHANOV
Keyword(s):  
Integral Equations ◽  
Risk Function ◽  
Numerical Procedure ◽  
Supremum Norm ◽  
Engineering System ◽  
Safety Device ◽  
Robot Safety ◽  
Natural Feature ◽  
Risk Criterion ◽  
Fast Repair

We consider the robot-safety device system as described in: Vanderperre and Makhanov, International Journal of Reliability, Quality and Safety Engineering 7 (2000) 169–175. The engineering system is characterized by the natural feature of cold standby and by a possible risky state. Apart from some tangible results obtained in the previous Literature, we introduce a risk function associated with the risky state of the robot. The risk function is determined by a coupled pair of convolution-type integral equations. In order to decide whether the risky state is admissible or reprehensible, we also introduce a suitable risk-criterion involving the supremum norm. We demonstrate that the criterion is always satisfied in the particular but important case of "fast" repair. Finally, we propose a numerical procedure to solve the system of integral equations and we calculate the underlying risk function.

RISK ANALYSIS OF A ROBOT–SAFETY DEVICE SYSTEM SUBJECTED TO A PRIORITY RULE

2012 ◽  
Vol 26 (2) ◽  
pp. 295-306 ◽  
Author(s):  
Edmond J. Vanderperre ◽  
Stanislav S. Makhanov
Keyword(s):  
Integral Equation ◽  
Risk Analysis ◽  
Explicit Solution ◽  
Priority Rule ◽  
Safety Device ◽  
Robot Safety ◽  
Type Integral ◽  
Risk Criterion ◽  
Direct Numerical Solution ◽  
Fast Repair

We introduce a robot–safety device system characterized by cold stand-by and by an admissible risky state. The system is attended by a single repairman and the robot has overall (break-in) priority in repair with regard to the safety device. We obtain an explicit formula for the point availability of the robot via an integral equation of the renewal-type. The explicit solution requires the notion of effective repair-versus-virtual repair. In order to decide whether the risky state is admissible, we also introduce a risk criterion. The criterion is always satisfied in the case of fast repair. As an example, we consider the case of Weibull–Gnedenko repair and we display a computer-plotted graph of the point availability obtained by a direct numerical solution of a convolution-type integral equation.

Analysis of R-out-of-N repairable systems: the case of phase-type distributions

2004 ◽  
Vol 36 (1) ◽  
pp. 116-138 ◽  
Author(s):  
Yonit Barron ◽  
Esther Frostig ◽  
Benny Levikson
Keyword(s):  
Repairable System ◽  
Repairable Systems ◽  
Regenerative Processes ◽  
Numerical Examples ◽  
Independent Components ◽  
Duality Results ◽  
Phase Type ◽  
Phase Type Distributions ◽  
Two Systems ◽  
Repair Facility

An R-out-of-N repairable system, consisting of N independent components, is operating if at least R components are functioning. The system fails whenever the number of good components decreases from R to R-1. A failed component is sent to a repair facility. After a failed component has been repaired it is as good as new. Formulae for the availability of the system using Markov renewal and semi-regenerative processes are derived. We assume that either the repair times of the components are generally distributed and the components' lifetimes are phase-type distributed or vice versa. Some duality results between the two systems are obtained. Numerical examples are given for several distributions of lifetimes and of repair times.

scholarly journals A New Approach for Analyzing the Reliability of the Repair Facility in a Series System with Vacations

2012 ◽  
Vol 2012 ◽  
pp. 1-16
Author(s):  
Renbin Liu ◽  
Yong Wu
Keyword(s):  
Renewal Process ◽  
Decomposition Method ◽  
Process Theory ◽  
Series System ◽  
New Approach ◽  
Numerical Examples ◽  
Special Cases ◽  
The Mean ◽  
Repair Facility

Based on the renewal process theory we develop a decomposition method to analyze the reliability of the repair facility in ann-unit series system with vacations. Using this approach, we study the unavailability and the mean replacement number during(0,t]of the repair facility. The method proposed in this work is novel and concise, which can make us see clearly the structures of the facility indices of a series system with an unreliable repair facility, two convolution relations. Special cases and numerical examples are given to show the validity of our method.

On the two sided barrier problem

1965 ◽  
Vol 2 (01) ◽  
pp. 79-87
Author(s):  
Masanobu Shinozuka
Keyword(s):  
Random Process ◽  
Ground Motion ◽  
Lower Bounds ◽  
Present Method ◽  
Structural Response ◽  
Random Processes ◽  
Upper And Lower Bounds ◽  
Numerical Examples ◽  
Long Run ◽  
Barrier Problem

Upper and lower bounds are given for the probability that a separable random process X(t) will take values outside the interval (— λ 1, λ 2) for 0 ≦ t ≦ T, where λ 1 and λ 2 are positive constants. The random process needs to be neither stationary, Gaussian nor purely random (white noise). In engineering applications, X(t) is usually a random process decaying with time at least in the long run such as the structural response to the acceleration of ground motion due to earthquake. Numerical examples show that the present method estimates the probability between the upper and lower bounds which are sufficiently close to be useful when the random processes decay with time.

TWO COMMODITY COORDINATED INVENTORY SYSTEM WITH MARKOVIAN DEMAND

2006 ◽  
Vol 23 (04) ◽  
pp. 497-508 ◽  
Author(s):  
V. S. S. YADAVALLI ◽  
G. ARIVARIGNAN ◽  
N. ANBAZHAGAN
Keyword(s):  
Probability Distribution ◽  
Inventory System ◽  
Poisson Processes ◽  
Expected Cost ◽  
Numerical Examples ◽  
Cost Rate ◽  
Continuous Review ◽  
Long Run ◽  
Operational Characteristics ◽  
The One

This paper considers a two commodity continuous review inventory system. The demand points for each commodity are assumed to form Poisson processes. It is further assumed that the demand for the first commodity require the one unit of second commodity in addition to the first commodity with probability p1. Similarly, the demand for the second commodity require the one unit of first commodity in addition to the second commodity with probability p2. This assumption model the situation in which a buyer who intends to buy one particular commodity may also go for another commodity. The limiting probability distribution for the joint inventory levels is computed. Various operational characteristics, expression for the long run total expected cost rate is derived. The results are illustrated with numerical examples.

scholarly journals Management of the Pandemic: Agriculture, Food Management and Resilience During Covid-19 in India

2021 ◽  
Vol 67 (3) ◽  
pp. 324-336
Author(s):  
Pushpa Singh
Keyword(s):  
Food Security ◽  
Food Systems ◽  
Agricultural Activities ◽  
Entire System ◽  
Farming Practices ◽  
Vulnerable Communities ◽  
Long Run ◽  
Food Management ◽  
The Impact

This article aims to analyse the impact of Covid-19 on agricultural activities, food security and policies of food management during the pandemic in India, particularly with reference to hardships caused to the most vulnerable communities due to the loss of livelihood, issues of access and availability. The explorations suggest that the growing inclination to centralise the structure of contemporary food and farming would make the entire system fragile, further accentuating the issues of food insecurity in the country. On the other hand, the localised, diverse systems of farming practices existing in various parts of India are rooted in agroecology, judiciously using and conserving the local natural resources. Thus, they have emerged as not only sustainable in the long run but are also food secure. While this impending crisis has exposed the systemic weakness of globalised food systems like never before, it also provides us with a crucial opportunity to mend our food and farming, keeping the long-term sustainability and food security as the goals.

scholarly journals Optimal Maintenance of a Production-inventory System With Continuous Repair Times and Idle Periods

2020 ◽  
Vol Volume 14 ◽  
Keyword(s):  
Preventive Maintenance ◽  
Average Cost ◽  
Inventory System ◽  
Control Limit ◽  
Raw Material ◽  
Production Unit ◽  
Numerical Examples ◽  
Long Run ◽  
Production Inventory ◽  
Production Inventory System

In this paper two similar models for the maintenance of a production-inventory system are considered. In both models, an input generating installation supplies a buffer with a raw material and a production unit pulls the raw material from the buffer. The installation in the first model and the production unit in the second model deteriorate stochastically over time and the problem of their optimal preventive maintenance is considered. In the first model, it is assumed that the installation, after the completion of its maintenance, remains idle until the buffer is evacuated, while in the second model, it is assumed that the production unit, after the completion of its maintenance, remains idle until the buffer is filled up. The preventive and corrective repair times of the installation in the first model and the preventive and corrective repair times of the production unit in the second model are continuous random variables with known probability density functions. Under a suitable cost structure, semi-Markov decision processes are considered for both models in order to find a policy that minimizes the long-run expected average cost per unit time. A great number of numerical examples provide strong evidence that, for each fixed buffer content, the average-cost optimal policy is of control-limit type in both models, i.e. it prescribes a preventive maintenance of the installation in the first model and a preventive maintenance of the production unit in the second model if and only if their degree of deterioration is greater than or equal to a critical level. Using the usual regenerative argument, the average cost of the optimal control-limit policy is computed exactly in both models. Four numerical examples are also presented in which the preventive and corrective repair times follow the Exponential, the Weibull, the Gamma and the Log-Normal distribution, respectively.

scholarly journals Study of the Insolvency and Bankruptcy Code 2016

2019 ◽  
pp. 221-233
Author(s):  
Vritti Bang ◽  
Shreyansh Bhansali ◽  
Devansh Doshi ◽  
Asawari Vedak
Keyword(s):  
Financial Institutions ◽  
Default Risk ◽  
Entire System ◽  
Public Sector Banks ◽  
Long Run ◽  
Credit Default ◽  
Bankruptcy Code ◽  
The Impact ◽  
Regulation Changes ◽  
Transparency Method

India has been riddling since decades with the problem of insolvency and bankruptcy issues. Several public sector banks, financial institutions and operational creditors were facing severe credit default risk. Various laws and codes have been passed as a corrective measure, but have proved to be inefficient and failed to provide any kind of relief to the creditors. There was thus a need for reform in insolvency and bankruptcy laws. The Insolvency and Bankruptcy code 2016 (IBC) has been instrumental in creating a shift in the way the bankruptcy process of defaulting firms has been dealt with. The IBC 2016 promises to bring about transparency, method and infrastructure in the entire system of liquidation. Changing up core aspects of the insolvency process, it gives companies a well-deserved chance at revival. Despite the recent amendments to the code and regulation changes by the Insolvency and Bankruptcy Board of India, there are still few grey areas in the code. This paper aims to thus test the effectiveness of the IBC 2016 since its introduction in 2016 and whether it resolves lags in the previous system. Hence, the paper dwells into the various components of IBC to critically analyse its sustainability and scalability. The research paper is purely based on secondary research through different news articles and reports from reliable sources. Though it is too early to comment on the impact of the IBC 2016, the researchers have tried to study the code and conclude whether it will be successful in fixing the problems and will keep up to its promise in the long run.

Applications of Piezoelectricity: Home safety device

2020 ◽  
pp. 59-66
Author(s):  
Mantavya Sehgal ◽  
Mayank Uttam ◽  
Nikhil Mantry ◽  
Rajiv Chaudhary
Keyword(s):  
Electric Charge ◽  
Pressure Difference ◽  
Piezoelectric Effect ◽  
Piezoelectric Plate ◽  
Entire System ◽  
Home Safety ◽  
Safety Device ◽  
Parallel Orientation ◽  
Voltage Difference ◽  
Piezoelectric Plates

The following piezoelectric security doormat is a safety device based on the piezoelectric effect and its converse. Pressure exerted by the person on the doormat is detected by the piezoelectric plates lined inside the mat. These piezoelectric plates are connected in a parallel orientation to make the doormat more durable because if a single piezoelectric plate becomes dysfunctional, the remaining branches will still work and keep the entire system operational. Once the pressure is detected, an electric charge is generated due to the piezoelectric effect. This electric charge is sensed by the Arduino. The coding of the Arduino is done in such a way that whenever it senses an electrical input, the piezo buzzer attached to it is turned on. This piezoelectric buzzer works on the principle of inverse piezoelectric effect where the voltage difference applied induces mechanical stress on the plates producing vibrations. Thus, the security doormat on sensing pressure difference whenever someone stands on it turns on the buzzer connected to it and therefore, alerts the residents.

Sign in / Sign up

Export Citation Format

Share Document