DEVELOPING BUSSINESS AND USER MEASUREMENT OF THE SYSTEM AVAILABILITY

This work presents basic elements of availability measurement methodology in complex technical systems according to business and users aspect. Methodology, which is primarily related to IT1 systems, is applied to and presented as a case study of Information system of Tax administration - DIS 2003. To achieve designed objectives of implemented methodology, it is necessary to provide "common" measurement from two different aspects: technical and business. The measurement result is system availability level as well as clear identification of critical components that influence the IT infrastructure stability and assure service continuity provided by the system

TECHNICAL SUPPORT AS A BASIS OF HIGH AVAILABILITY LEVEL AND IT SYSTEM SERVICE QUALITY

This work presents the development and implementation methodology of technical support in IT1system operation. Methodology is developed and applied in realistic system (Information system of the Tax administration - DIS 2003), which is technically very complex and highly distributed. The results of IT system availability assessment and identification of the critical components are input parameters in the process of establishing of the technical support. The importance of technical support for achieving optimal IT system availability and IT service quality is assessed according to its operation during one year. The history of technical support system operation is a basis for further continuous improvement

Squeeze Film Effect in Surface Micromachined Nano Ultrasonic Sensor for Different Diaphragm Displacement Profiles

In the present paper, we have analytically explored the small variations of the local pressure in the trapped air film of both sides of the clamped circular capacitive micromachined ultrasonic transducer (CMUT), which consists of a thin movable membrane of silicon nitride (Si3N4). This time-independent pressure profile has been investigated thoroughly by solving the associated linear Reynold's equation in the framework of three analytical models, viz. membrane model, plate model, and non-local plate model. The solution involves Bessel functions of the first kind. The Landau-Lifschitz fringing technique has been assimilated to engrave the edge effects in estimation of the capacitance of CMUT, which should be considered in the micrometer or lesser dimension. To divulge the dimension-based efficacy of the considered analytical models, various statistical methods have been employed. Our use of contour plots of absolute quadratic deviation revealed a very satisfactory solution in this direction. Though the analytical expression of the pressure profile is very cumbersome in various models, the analysis of these outputs exhibits that the pressure profile follows the displacement profile in all the cases indicating no viscous damping. A finite element model (FEM) has been used to validate the systematic analyses of displacement profiles for several radii and thicknesses of the CMUT's diaphragm. The FEM result is further corroborated by published experimental results bearing excellent outcome