Dan Iudean

Reliability Indicators and a Failure Mode and Effect Analysis Calculation for a Holter Recorder

Product reliability is very important nowadays, and everyone seeks products that will last very long without failing. It is hard to make a product good and reliable without investing in reliability research from the early stages of the design. This paper presents a reliability analysis for a Holter Recorder for home use, and also a Failure Mode and Effect Analysis using Relex software. This approach can be used for any similar device and helps the manufacturer design a better product.

Reliability indicators analysis for the cam box module of industrial knitting machines

This paper studies the reliability of an industrial knitting machine, emphasizing the reliability value and the reliability indicators: failure rate and MTBF (Mean Time Between Failures). This study has been conducted on an industrial knitting machine and has duration of 4500 hours (approximately 6 months), after which preventive maintenance operations are planned. This study analyses the behavior of the reliability, failure rate and of the MTBF depending on the functioning environment and of the temperature to which the knitting machine was subjected. The last part presents an analysis of the top ten components that are most likely to malfunction.

Reliability modeling for an automatic level control system

Water resource availability is an important problem as water is basically used for everything we make. In a water distribution process the level and flow must be always controlled. Therefore, the parameters of the system must be known at any moment. This paper presents an automatic level control system which is analyzed in terms of reliability in order to present solutions to clarify how such systems could be designed as robust as possible.

Reliability assessment of linear generator type wave energy converters

Wave energy is an important renewable source of electricity that can be exploited. The reliability is an important issue for these energy converters due to the fact that they must be installed in harsh environments. The paper presents a reliability analysis of the linear generator type wave energy converters and shows the impact of the environment on the components of these devices.

Markov analysis of an induction motor

The paper deals with the reliability of induction motors by using Markov techniques. The basis of this process is to perform the reliability predictions to obtain the necessary indicators in order to support the Markov analysis. The analysis is made on a single-phase induction motor, taking into consideration the most critical components that could lead to the failure of the motor. Furthermore, the possible states of the motor and the importance of maintenance in the lifecycle of the motor are presented. By having a well implemented maintenance policy, the life of the motor can be extended and unwanted defects can be avoided.

Didactic Application for Monitoring Biomedical Parameters and Data Transfer over the Network Using Virtual Instrumentation

Telemedicine is used on a large scale for monitoring the state of a patient and permits the real-time contact between the doctor and the patient. The software applications and the TCP/IP protocols, combined with the data acquisition techniques, allow the doctors and engineers to cooperate towards reliable medical equipment and solutions.

Implementing an Failure Mode and Effect Analysis for Small and Medium Electric Motors Powered from Photovoltaic Panels

Abstract The article approaches the issue of small and medium sized electric motors. This is part of an extended study, which contains an algorithm for computing all the statistical and reliability indicators used in the design and analysis of electric motors and also the general system which include these types of motors. The general system is composed by a photovoltaic panel for power supplying, the charger and the battery module, the control module and the motor part of the system. The present paper emphasizes the FMEA analysis, considering the usual faults which might occur in the running of the mentioned electric motors. Thus, the influences of constructive elements of a motor on its reliability are computed (mode percentage); the prediction of the number of occurrences of a fault during the maximal running period of a motor, the analysis of risk level for small and medium electric motors and determining critical values for the motors elements (mode criticality).

Considerations regarding the determination of active and reactive power in three-phase circuits using Hilbert dephasing operator

The measurement of the active and reactive power in three-phase circuits is a field considered closed, in which all the models have been exhausted, in which there are no other ways to investigate and innovate. These statements are generally accepted by the design engineers and viewed with reticence by a small number of researchers. This paper does not attempt to change these opinions so securely fixed in professional circles from measurements domain; it involves a new method of separating the active and reactive power in three-phase circuits: in active and reactive power due to symmetrical components of direct sequence and in symmetrical components of negative sequence. It essentially consists in a method to obtain the symmetrical components of direct and reverse sequence. Unlike the classic mode of determining such size in the phasor form, the paper uses as a method of determination in instant quantities form. For this purpose, a dephasing Hilbert operator is used.

Aspects Regarding the Unidirectional Two-Port Circuits Implemented by Means of Electronic Gyrators

The paper investigates the behavior of unidirectional two-port equivalent circuit composed of an electronic gyrator with Antoniou operational amplifier and a reciprocal two-port built ...

Carbon Monoxide pollution map in the center of Cluj-Napoca City

This article is dedicated to the study of Carbon Monoxide levels in the city of Cluj-Napoca. The data was collected during an eight months period and was interpreted after all the information was gathered. The study has shown that pollution in the center of the city under analysis is causing the levels of carbon monoxide to triple, in comparison to outer regions, further from the intense traffic. The study has revealed that the distribution of carbon monoxide is fairly uniform over the area that was studied.