16 research outputs found
Supercapacitors: The Innovation of Energy Storage
In addition to the accelerated development of standard and novel types of rechargeable batteries, for electricity storage purposes, more and more attention has recently been paid to supercapacitors as a qualitatively new type of capacitor. A large number of teams and laboratories around the world are working on the development of supercapacitors, while their ever-improving performances enable wider use. The major challenges are to improve the parameters of supercapacitors, primarily energy density and operating voltage, as well as the miniaturization, optimization, energy efficiency, economy, and environmental acceptance. This chapter provides an overview of new techniques and technologies of supercapacitors that are changing the present and future of electricity storage, with special emphasis on self-powering sensor and transmitter systems. The latest achievements in the production, modeling, and characterization of supercapacitor elements (electrode materials, electrolytes, and supporting elements) whose parameters are optimized for long-term self-supply of low power consumers (low voltage, high energy density, and low leakage current, etc.) are considered
Postoperative complications in patients undergoing thyroid surgery
Background and objectives: Postoperative complications from thyroid surgery are numerous
and may be shown on different levels. Some of these complications may be detrimental for patients,
so minimization of the risks should be always considered. We evaluated the postoperative complications in patients after surgery of the thyroid gland at the Clinic for Thoracic Surgery, Skopje.
Material and method: In retrospective manner, all patients undergoing thyroid surgery
during the one-year period (1. January- 31. December 2017) were evaluated. Patients were divided into two groups, whereas group ST included patients who underwent goiter removal and
subtotal thyroidectomy while group TT included patients in who total thyroidectomy was done.
In both groups we analyzed the demographic data and the occurrence of postoperative (in the first
48 hours) complications (stridor, hoarseness, hemorrhage, nerve dysfunction, tracheomalacia,
hypocalcemia and the need for reintubation and tracheostomy).
Results: Total data from 197 patients was evaluated. 120 patients had subtotal thyroidectomy
while total thyroidectomy had 77 patients. Postoperative complications occurred in significantly larger
number of patients in the TT group (64.9 vs. 40%). Hoarseness (8.4% vs. 18.5%), stridor (18.3%
vs. 9.2%) tracheomalacia (5% vs. 1.2%) and hematoma (2.5% vs. 3.8%) occurred in respect to the
groups. Hypocalcaemia occurred in significantly larger number of patients in TT group. Permanent
nerve injury was found in one patient in the same group and tracheotomy was done only in one patient.
Conclusion: Overall results from our study show that the complications after thyroid surgery
occur in all patients who undergo thyroid surgery. However, more severe complications and
outnumbered are complications in patients who undergo total thyroidectomy.
Key words: complications, occurrence, thyroid surgery, total thyroidectomy
Supercapacitor Design and Applications
In this book, authors investigated asymmetric and symmetric supercapacitor configurations for different electrode materials. Besides the already standard activated carbon (AC), studies were done with other materials and technologies for their preparation and activation. Also, the research info was presented with different electrolytes in order to obtain a higher capacitance and potential window, with as small as possible serial resistance. Achieved high performance enables wide application, and some of the new applications (spacecraft power systems, powering heart pacemakers and wireless sensors) are also described in this book
Thermovisual camera commands decoding and ISI format encrypting
523-528This study describes wiretapping method for camera and its monitoring codes. Analysis and decoding of specially protectedISI database includes temperature data of an object observed in the process
Modeling, Simulation, and Computer Control of a High-Frequency Wood Drying System
High-frequency wood drying is the modern method used in raw wood drying so that treated wood can be used further in various processes. Such systems are used because of the economy, energy efficiency, obtaining of good mechanical properties of the wood after treatment, as well as reducing time consumption. Therefore, it is extremely important to understand each component of such systems and processes. The mentioned systems are implemented using high-frequency generators based on vacuum tubes (VT). Their development and, in particular, optimization are by far more complex than the transistor systems; therefore, the development is now compelled to rely on computer modelling and simulation. In this research, a high-frequency (HF) generator of 20 kW output power and 1.5–15 MHz adjustable frequency based on VT was produced and then, with the corresponding model for VT itself and the rest of the developed circuit, was followed by computer simulation and real-system measurement. The model parameters were adjusted, which provided additional system optimization. An extra match of the results from the simulation and measurement was obtained; thus, the optimization was performed faster and more precisely. In addition, an easier and quicker way of adjusting parameters of the PID controller using a developed software-based control system was attained. The problems of cooling the VT anode under high DC voltage, as well as temperature measurement in the HF electric field, have been solved
The influence of cupric ions on shape of potentiodynamic curves obtained on 18 K gold
The shape of potentiodynamic curves depends mainly on the composition of investigated alloys, but also on the electrolyte used in experiments. In this work investigation were performed for pure gold, and pure silver and copper as alloying metals, then for binary alloys Au-Ag and Au-Cu containing gold as in 18 k gold (i.e. 75 % Au) and Ag-Cu with mass ratio 1:1 and, finally, for three component 18 k gold. It was established a catalytic effect of cupric ions present in electrolyte on oxidation of gold and 18 k gold alloys