•Two different real time simulators designs were presented and compared in the paper.•Both designs are based on the Simulink and on the real time Linux.•First design is using DAQ cards as the I/O ...interface.•Second design is using IEC61850-based Ethernet communication as the I/O interface.•Both designs provide cheaper alternative for the commercial solutions.
Hardware-in-the-loop simulations might be considered as the most advanced method of power system protection testing. However, availability of these devices remains significantly low due to the cost barrier and sizes of the simulator. A rapid growth of the Matlab/Simulink tools and IEC61850 open source libraries in recent years has opened the possibilities of designing proprietary real time simulators that are comparable with commercial solutions. This paper presents two simulator designs - one based on DAQ cards and the second one based on IEC61850 services. The performance limits of the simulators in the real time were compared in this paper. Furthermore, it was proven that the performance of these simulators is sufficient to conduct successful tests of protection relays. Consequently, the examples of protection relays testing results were discussed. Finally, it was explained why the presented designs might substantially support new protection algorithms verification. It is due to the high availability and the reduced device size.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Software power protection tester implemented in a real-time operating system (RTOS) might replace the conventional testing setups in IEC 61850 protection systems. This paper describes an open power ...protection testing platform. Linux RT capabilities related to runtime environment for such a tester are examined and OS latency sources are identified and evaluated. An algorithm for a multithreaded tester operation is proposed, including Sampled Values (SV) publisher, GOOSE input/output and time synchronization. SV and GOOSE services implemented in RT Linux environment are evaluated in accordance with IEC 61850‒5 transfer time requirements. Linux PTP time synchronization service of two similar systems controlling its electrical ports is evaluated in different synchronization scenarios. The developed tester is compared to an equivalent conventional setup during the test of IED over-current function. The conducted tests show that the Linux implementation of power protection tester in the case of scheduler latency, time synchronization accuracy and transfer time all meet the requirements of IEC 61850.
The paper is related to an adaptive satellite communication system for data transmission from small, low cost, low Earth orbit satellites. Tests run in a set-up consisting of a number of ...software-defined radio (SDR) modules operating as a satellite, a ground station, and a satellite channel simulator, have shown that by changing modulation scheme and code rate one can obtain increase of amount of data which can be downloaded from a satellite during a single pass over a ground station approximately by a factor of 2. To determine data rates obtainable in an SDR system using a common personal computer as a digital signal processing device, execution times of particular processing steps involved in the reception process were measured.
Thyroid hormones (T
3
, T
4
) are well known modulators of different cellular signals including the sphingomyelin pathway. However, studies regarding downstream effects of T
3
on sphingolipid ...metabolism in skeletal muscle are scarce. In the present work we sought to investigate the effects of hyperthyroidism on the activity of the key enzymes of ceramide metabolism as well as the content of fundamental sphingolipids. Based on fiber/metabolic differences, we chose three different skeletal muscles, with diverse fiber compositions: soleus (slow-twitch oxidative), red (fast-twitch oxidative-glycolytic) and white (fast-twitch glycolytic) section of gastrocnemius. We demonstrated that T
3
induced accumulation of sphinganine, ceramide, sphingosine, as well as sphingomyelin, mostly in soleus and in red, but not white section of gastrocnemius. Concomitantly, the activity of serine palmitoyltransferase and acid/neutral ceramidase was increased in more oxidative muscles. In conclusion, hyperthyroidism induced fiber specific changes in the content of sphingolipids that were relatively more related to de novo synthesis of ceramide rather than to its generation via hydrolysis of sphingomyelin.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
In this paper, we present the application of a neural network for events classification in a high-energy physics experiment. As a network model we use a multi-layer perceptron with a dynamic topology ...adjustment algorithm. Our solution covers both adding new hidden neuron units and removing unnecessary units. Neural network results are compared to the standard kinematical cuts techniq1guuuuue and to the well-known k-nearest neighbour classifier.
Abstract Background Ovarian serous cystadenomas are rare in children. No case of recurrence after surgical resection in a premenarchal girl has been published. Case An 8-year-old presented with ...abdominal pain and ultrasound showed bilateral ovarian cystic masses with normal clinical and laboratory exam. Cystectomies were performed revealing serous cystadenomas. Ten months later, her pain returned and ultrasound showed new cysts. Persistence of cysts and symptoms required repeat surgery with the same pathology. Summary and conclusion Premenarchal girls with ovarian cystic masses require surgical intervention in cases of persistent symptoms, uncertain diagnosis, or concern for ovarian torsion. With reassuring imaging and tumor markers, conservation of the ovary can be achieved with cystectomy alone. Ultrasound follow-up is recommended after surgical resection until bimanual exam can be performed.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The aim of the study was to evaluate the nitrogen removal and its effects on the plant's growth and leaves morphology. using two subsurface vertical flow (VF bed), with different depths (0.24 m
2
× ...0.70 m; 0.24 m
2
× 0.35 m) and nitrogen load increments. The VF bed were planted with Vetiveria zizanioides, filled with light expanded clay aggregates (Leca®NR 10/20) and fed in parallel mode with synthetic wastewater. High ammonium nitrogen concentration (NH
4
+
-N from 68 ± 3 to 290 ± 8 mg L
−1
) was used without toxicity symptoms in plants, although the effects of ammonium nitrogen load were stopped the growth of the plants. Significant differences between ammonium nitrogen removed in each VF bed obtained for total nitrogen (TN
infl
.) ≥ 27 ± 0.8 g m
−2
d
−1
. The nitrification was contributed to ammonium nitrogen removal because was found higher values of nitrate and nitrite in the effluent. These values were more higher in VF bed 1 than in the VF bed 2, since ammonium nitrogen removal were also more higher in VF bed 1 than in the VF bed 2. Total nitrogen mass balance was carried out and the results show that the nitrification/denitrification process occurred with nitrogen plants uptake. It was observed that the VF bed depth has an influence on all nitrogen removal processes. As higher the depth root system it is seemed to favour the creation of zones with different oxidations conditions that allow the nitrogen compounds to be removed intensively.
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BFBNIB, GIS, IJS, KISLJ, NUK, PNG, UL, UM, UPUK
A sum rule of superconvergence type for parity violating amplitudes (p.v. analogue of the Gerasimov-Drell-Hearn sum rule) is discussed. The parity violating polarized photon-induced processes for the ...proton target are considered in the framework of effective low energy theories and phenomenological models based on p.v. nucleon-meson effective interactions. It is argued that the verification of the sum rule in future high intensity polarized photon beam experiments is feasible.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Dissolution of guanine in neutral solutions was obscured by peculiar behavior of guanine, indicating an apparent dependence of solubility on the amount of solid guanine used. Here, we demonstrate ...that the problem is caused by the formation of tiny guanine nanoparticles that tend to grow forming stable particles of ca. 800 nm size. This effect can be minimalized by using small quantities of guanine powder for dissolution. We also show that assuming a constant, independent of pH, concentration of neutral form of guanine, at 25 °C equal 25.4 μM, and applying known pK a values related to its dissociation or protonation, it is possible to calculate the concentrations of all conjugate acids and bases of guanine at the given pH value, and by summing them up, the guanine solubility.
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