Methods for checking the sensitivity of a toroidal compensated current comparator and its inherent errors and auxiliary circuits are described in this paper. Results of the measurements are also given in graphical form.

Anesthetic gaseous components are necessary to be evaluated in hospital facilities, especially in surgical pavilions. Exposure to anesthetic gases in the health sector, whether in the operating room, recovery room, or in the context of outpatient clinics, may entail a health risk for the personnel exposed. Although health care workers are exposed to much lower anesthetic concentrations than the patients, this exposure often extends over many years. Personnel often indicate fatigue and headaches, especially when occupational hygiene conditions are inadequate. The decisive factors as concerns, the adverse health effects of exposure to anesthetic gases, are mainly the type of gases used, the length of exposure, and the gas concentrations. This paper aims to describe an attempt (successful) to design a sensor control unit in order to improve photoacoustic instrumentation.

This paper develops the synthesis of some elementary cubic spline virtual instruments associated to the symbolic transmittance of circuits. The implementation of these virtual instruments is based on the power of LabVIEW programming language to develop modular applications. The method has a pronounced educational purpose and can be used in electric and electronic circuits time analysis. The general symbolic transmittance of such circuits is expressed like a linear combination of elementary symbolic transmittances. An elementary first or second order differential equation is associated to an elementary symbolic transmittance. The solutions of this equation are given by a third order spline approximates and the algorithms lead to the synthesis of inferior order spline virtual instruments. Using a cascade connection of such elementary virtual instruments, a high order virtual instrument associated to the general symbolic transmittance is obtained. Finally, the circuit response can be determined.

Measurement instruments capable communicate with remote controller are mainly used in today measurement systems. In our case software has been written that turned the microprocessor based measuring board into SCPI measuring device (SCPI- Standard Commands for Programmable Instruments). We wrote a SCPI interpreter that enables compatibility with SCPI 1999 standard. First the software has been written that enables microprocessor module to communicate via IEEE 488 bus. Then some routines have been added that enable format compatibility between microprocessor and control software at the remote computer. The developed software is universal platform for supporting the open architecture technology of virtual instruments.

The paper describes methods and the dedicated instrumentation set-up used for characterization the behaviors of the absorbing materials. The described methods are based on the free space measurement with a receiving/transmitter antenna and a directional coupler as an ending path of the vector analyzer. Various methods are tested for cancellation of the unwanted signals and for an adequate characterization of the true reflection/absorption coefficients for composite materials and Salisbury screen.