Service Life Of Units Research Articles

Integrating a Positron Emission Tomography/Computed Tomography Into the National Health System of Cyprus: Will It Return on Its Investment?

A European Union (EU) member state, Cyprus is a country with a population of ~850,000 citizens. According to the Cyprus Ministry of Health, since 2009, more than 3,000 new incidents with neoplasm are diagnosed every year (i.e., 3% increasing rate). Projections estimate an average annual increase of 2.2% of new incidents until 2040. However, the National Health System (NHS) of Cyprus lacks a Positron Emission Tomography/Computed Tomography (PET/CT) care framework and infrastructure. Patients can only have a PET/CT exam in the private sector, either in Cyprus or a neighboring country (e.g., Greece or Israel). This requires the government of Cyprus to cover financial expenses related to medical treatments while the patients may also need to cover their expenses for traveling to a neighboring country. This study presents a cost analysis to examine whether the integration of a PET/CT with, or without, an F18-FDG cyclotron unit in the NHS of Cyprus is an efficient investment that can be recovered within the unit's service life. To perform this study, we estimated necessary resources for purchasing and operating such unit for a period of 15 years. The results of this study indicate that an investment in a PET/CT unit is not financially viable. Alternatives, such as the reimbursement of PET/CT operated by the private sector is recommended.

ОПЕРАТИВНЫЙ МОНИТОРИНГ И УПРАВЛЕНИЕ ТЕМПЕРАТУРНЫМИ РЕЖИМАМИ РЕСУРСНОЗНАЧИМЫХ АГРЕГАТОВ АВТОТРАКТОРНОЙ ТЕХНИКИ

When operating automotive equipment at low or high ambient temperatures, various devices are required to maintain the thermal regime of the units in the permissible range, which significantly affect the internal energy consumption and the service life of the machine. Currently, such a complex thermal preparation is implemented only for the engine by heating or cooling the coolant. For other systems and units, continuous monitoring of their temperature is not provided, and there are no rules or clear requirements for the implementation of such heat preparation. (Research purpose) The research purpose is in expanding the functionality of remote diagnostics by operational monitoring and control of the temperature conditions of individual machine units. (Materials and methods) Authors used research methods based on the application of standard techniques, the object of research was the system of integrated thermal automotive equipment. In addition to heating the engine before starting, other systems and units need to optimize the thermal regime, most of which can be combined into a comprehensive heat treatment system. (Results and discussion) As a result of experimental studies of the integrated heat treatment system mounted on a KAMAZ vehicle, the dynamics of temperature changes in various units during their heat treatment were and presented. Monitoring and controlling the temperature regime of automotive equipment units will reduce internal power losses and increase the service life of units exposed to temperature. (Conclusions) The introduction of a comprehensive heat treatment system, intelligently and functionally linked to a remote monitoring system, will significantly increase the service life of the units most exposed to temperature influences.

ОПЕРАТИВНЫЙ МОНИТОРИНГ И УПРАВЛЕНИЕ ТЕМПЕРАТУРНЫМИ РЕЖИМАМИ РЕСУРСНОЗНАЧИМЫХ АГРЕГАТОВ АВТОТРАКТОРНОЙ ТЕХНИКИ

When operating automotive equipment at low or high ambient temperatures, various devices are required to maintain the thermal regime of the units in the permissible range, which significantly affect the internal energy consumption and the service life of the machine. Currently, such a complex thermal preparation is implemented only for the engine by heating or cooling the coolant. For other systems and units, continuous monitoring of their temperature is not provided, and there are no rules or clear requirements for the implementation of such heat preparation. (Research purpose) The research purpose is in expanding the functionality of remote diagnostics by operational monitoring and control of the temperature conditions of individual machine units. (Materials and methods) Authors used research methods based on the application of standard techniques, the object of research was the system of integrated thermal automotive equipment. In addition to heating the engine before starting, other systems and units need to optimize the thermal regime, most of which can be combined into a comprehensive heat treatment system. (Results and discussion) As a result of experimental studies of the integrated heat treatment system mounted on a KAMAZ vehicle, the dynamics of temperature changes in various units during their heat treatment were and presented. Monitoring and controlling the temperature regime of automotive equipment units will reduce internal power losses and increase the service life of units exposed to temperature. (Conclusions) The introduction of a comprehensive heat treatment system, intelligently and functionally linked to a remote monitoring system, will significantly increase the service life of the units most exposed to temperature influences.

Some aspects of the VVER-440 reactor plant life re-extension: a case study of the Novovoronezh NPP Unit 4

The re-modernization of Unit 4 at the Novovoronezh NPP (Novovoronezh-4) made it possible to take a new approach to the problem of extending the VVER-440 reactor plant life and operation. The authors analyze the existing problems of the VVER-440/179 power unit, showing possible solutions to the identified shortcomings and the final state of the updated power unit. Modernization works significantly expanded the range of design-basis accidents from the primary coolant leak from an opening (DN = 100 mm) to the maximum possible, associated with a rupture of the main circulation pipelines (MCP) (DN = 500 mm). A unique experience was gained in using the safety systems of Unit 3, which was finally shutdown for decommissioning, to increase reliability and provide additional redundancy for the safety systems of Unit 4. The results of the performed works showed the correctness of the adopted concept of re-extending the service life of Unit 4 and ensured its compliance with the modern safety requirements in nuclear power engineering, including as it relates to the safety impact of the first-level probabilistic safety analysis model (PSA-1) for internal initiating events.

Life Estimation of Hub Bearing Unit Based on Test Load Spectrum

In the paper, the steady-state steering dynamics model of the cars is firstly established. Then, three degree of freedom model of double row angle contact ball bearing is established. Based on the mathematical model and load spectrum, wheel hub bearing unit service life is calculated and estimated. The analysis results of the service life influencing factors have an important guiding significance for the design and use of hub bearing unit.

Upgrading optics test capabilities for modern weapon systems

The terms obsolete and obsolescence are heard in almost every industry today. For suppliers and users of test systems facing product obsolescence, these terms represent both opportunities and challenges depending upon one's perspective. For manufacturers of replacement items, it represents new business possibilities, and for those maintaining the systems, it can mean investment and expense. By offering replacement solutions for obsolete instrumentation, the life of test systems can be cost-effectively extended. This paper presents the requirements and features associated with the development of an Infrared Target Simulator utilized by the Air Force to test IR (InfraRed) Seekers at the O-level, Depot, and I- level. The present legacy test simulator was a stand-alone, bulky, off axis design that became no longer producible or repairable due to obsolete hardware. The legacy system was also designed and manufactured at a time when modularity was not a consideration - a key feature for new modern systems which allows the production of new modules using current technology hardware and facilitating upgrades, extending the legacy test unit's service life.

Designing vibration strength tests of flight vehicle airborne equipment

In the framework of designing vibration tests for the airborne equipment units the types of fatigue curves of their elements are determined. A method for recounting the value of the specified unit service life with regard for only vibration effect is proposed. Variants of vibration strength bench tests are considered.

Pollution of the Heat Carrier and Its Influence on the Service Life of Power-Generating Units of Nuclear Power Plants

We present the data of autoclave testing of 10GN2MFA and 08Kh18N10T steels for cyclic crack-growth resistance in reactor borated water at a temperature of 300°C. We tested standard 25-mm-thick specimens for two values of the load ratio equal to 0.2 and 0.7. The loading frequency of specimens in the autoclave did not exceed 0.0167 Hz. We propose a model and a procedure of numerical evaluation of the increments of crack length according to the mechanisms of corrosion-fatigue and static corrosion cracking under the conditions of their combined action based on the analysis of principal characteristics of structural materials. Unlike the method based on the use of the Paris equation proposed by foreign standards, the method developed in the present work is more general and informative. Moreover, it includes the method used in standard specifications as a special case and enables one to explain the premature fracture of collectors of steam generators at the South-Ukrainian Nuclear Power Plant and other elements of power-generating units of the nuclear power plants. It is shown that, in the absence of corrosion-fatigue cracking, power-generating units of nuclear power plants can operate without emergency shutdowns for the entire service life. In the case where the heat carrier is polluted to a level sufficient for the initiation of the mechanism of static corrosion cracking, the service life of units to the time where the crack attains its critical size sharply decreases. We propose to improve the systems of water supply and perform continuous monitoring of the controlled parameters of the heat carrier and, in particular, of the contents of admixtures promoting the static corrosion cracking of steels.

Life Expectancy for Fossil Steam Turbine Casings after 1000 000 Hours

Abstract Today with the rapid development of nuclear electricity generation on a large scale, there arises the problem of maintaining fossil fuel generating stations that have been in operation for some 100 000 h or more. Operators usually hope to prolong the service life of units where safety margins permit, with objectives attaining beyond 150 000 h. This is an extremely ambitious program that is thwarted by the very nature of the work demanded from this type of thermal generating station: namely fulfillment of the needs of daily and seasonal peak periods, which increase the number of severe thermal operating transients. This paper examines the question of metallurgical studies carried out by Alsthom-Atlantique on stator steel castings with a view to estimating their expectation of life potential. This work constitutes the second part of a study entitled “Quenching, Tempering, and Aging of Chromium-Molybdenum-Vanadium Cast Steels” in the Journal of Evaluation and Testing, Vol. 9, No. 2, March 1981.