The Planck-Balance (PB) is a table-top version of a Kibble balance. In contrast to many existing Kibble balances, the coil is moved sinusoidally and an ac rather than a dc signal is generated in the dynamic mode. The three-parameter sine fitting algorithm is applied to estimate the amplitudes of the induced voltage and the coil motion, which are used to determine the force factor Bl of the voice coil of the electromagnetic force compensation balance. However, the three-parameter sine fitting algorithm is not robust against some perturbations, e.g. additive Gaussian white noise, quantization error, and frequency error. These effects have influences on the accuracy of the amplitude estimation. Based on numerical simulations and correlation analyses, the effects of these perturbations are determined. By optimizing measurement and data processing approach, the bias and standard deviation of the estimated amplitude could be effectively reduced, and thus the accuracy of the force factor Bl in the dynamic mode can be improved.

A new mathematical model for generating ECG signal is presented in this paper. The generation is based on geometrical properties of real ECG signals instead of various artificial function used in commonly applicated models. Variation of parameters allows arbitrary setting of particular waves of PQRST complex. This way arbitrary PQRST signals typical for various heart diseases can be modelled and generated with high fidelity. Moreover, parameter variation allows generate different waveform for each subsequent heartbeat without mixing PQRST waves order. The elementary trigonometric function and Gaussian monopulse have been used for modelling each particular wave. Adding a noise and/or respiratory signal the final synthetized artificial signal can be applied for various signal processing method testing. The model was tested by comparison of synthetized patterns against patterns generated by LabVIEW Biomedical Toolkit. The model is tested against the real ECG records from MIT-BIH arrhythmia database as well, while the model parameters are found using a differential evolution algorithm.

Numerous scientific disciplines such as hydrology, meteorology, oceanography or geology take advantage of remote measuring and monitoring. Data measurement in distant locations and the transmission of measured data is an essential part of these disciplines. The critical element of remote measurement and monitoring systems is a data collecting station. When designing such a device, it is necessary to solve issues of the construction, power system, data transfer or autonomous operation systems. This paper introduces the Autonomous Groundwater Monitoring Station with Wireless Communication which has been designed and installed in a field application. The individual parts of the station such as construction, software, hardware, wireless communication system or systems for autonomous operation are presented.

The redefinition of kilogram in terms of Planck constant rather than a physical artifact of International Prototype of Kilogram will be put into force in May 20^th, 2019. National Metrology Institute of Turkey contributes to the ongoing worldwide scientific work on the realization of kilogram with an Oscillating-Magnet Kibble Balance experiment. The novel dynamical measurement procedure developed for Kibble Balance Experiment in Turkey poses the advantage of being less sensitive to the environmental disturbances. Precise displacement measurements between the coil suspended from a balance and the surrounding magnetic circuit are vital to reach the required uncertainties in the realization experiments via Kibble balance. The Michelson Interferometer and the Fabry-Perot Interferometer are commonly used in precise displacement measurements in worldwide Kibble balances. A commercial, miniature, plane mirror Michelson Interferometer with compact sensor head is used in the Kibble Balance Experiment of Turkey. In this paper, we determine the contribution of ultra-small oscillations to Planck constant by taking simultaneous displacement measurements on two back-to-back mirrors attached to the piezoelectric transducer undergoing an oscillatory motion with Michelson Interferometer and Fabry-Perot Interferometer. Although, in the specification of these instruments it has been stated that extreme precautions are required in the environmental conditions to be able to measure displacements with ultra-small amplitudes, following the novel measurement procedure makes such measurements possible in a regular laboratory environment which allows us to investigate the resolution performance of these instruments in laboratory conditions. Consistent results with resolution uncertainties of 1.4 × 10^-9 and 2.2 × 10^-9 are obtained for Michelson Interferometer and the Fabry-Perot Interferometer, respectively. As the expected relative uncertainty in the redefinition experiments of the kilogram is above the resolution uncertainties of both interferometers, we may conclude that a commercial, miniature, plane mirror Michelson Interferometer with compact sensor head will serve for our purposes in the route for the redefinition of kilogram.

The complex random characteristics of smart grid lead to large dynamic errors of static electricity meters in electrical energy metering. According to the typical intrinsic characteristics of large power dynamic loads (LPDL), this paper firstly proposes a distorted m-sequence dynamic test (DmDT) signal model to reflect the characteristics. In addition, a likelihood function indirect testing method is also proposed to solve the problems of both static electricity meter dynamic error testing and dynamic reference electrical energy traceability. Then, a dynamic error testing system is also built for verifying the likelihood function indirect testing method under different DmDT signal conditions and the dynamic error testing results are given out. Experimental results show that the DmDT signal and the likelihood function indirect testing method are effective for dynamic error testing of static electricity meters. At last, the measurement uncertainty of the dynamic error testing system is better than 0.04% (coverage factor k = 2).