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This paper addresses the discharge characteristics of a multicell lithium-ion battery with nonuniform cells. By using a multicell battery with two different types of cell, we experimentally investigate the relationship between discharge capacity and battery topology. In the series connection of nonuniform cells, the total capacity of the battery is governed by a cell with the smallest capacity. In the parallel connection, the total capacity becomes the sum of cells in parallel. In a multicell battery with the series–parallel connection, the discharge capacity depends on its configurations such as connection and number of nonuniform cells. Also, we derive a mathematical model for discharge characteristics of the multicell battery based on the equivalent circuit model of an individual cell. For a multicell battery with a general configuration, the discharge capacity is successfully evaluated by numerical simulations of the mathematical model.

Cold atmospheric-pressure He + N(2) and He + O(2) plasmas are chosen as the representatives for electropositive and electronegative plasmas, of which the discharge characteristics are studied and then compared to each other by fluid models. As the increase of the impurity (N(2) or O(2)) fraction from 0 to 10%, for He + N(2) plasmas the electron density and ion density increase, the spatiotemporal distributions of electron density, ion density, electron temperature and electron generation rate change a little. On contrast, for He + O(2) plasmas the electron density decreases, the ion density first increases and then decreases, the electron temperature increases in the bulk region, but decreases in the sheath region, and the plasmas transform from γ mode to α mode as the significant change of electron generation rate distributions. Larger electric field is needed in the bulk region to sustain the electronegative plasma, so the electrical characteristics of He + O(2) plasmas transform form capacitive to resistive with increasing O(2) fraction. Meanwhile, the ion-coupling power increases dramatically, which can be estimated by a formula based on the electronegativity. A new criterion for determining the sheath boundary, |∇E| = 5 kV/cm^2, is put forward, which is found suitable for both the electropositive and electronegative plasmas.

Considering the ice shedding phenomena on ice-covered outdoor insulators, this paper conducted the artificial experiments by using a five-unit suspension ceramic insulator string covered with wet-grown ice to investigate the effects of ice shedding on the icing discharge characteristics. According to IEEE Standard 1783/2009, the minimum flashover voltage (VMF), propagation of discharges to flashover and related leakage current (LC) were measured. It was found that VMF after ice shedding can be increased by about 17% as compared with that before ice shedding. The initiation and formation of discharge arcs across ice-free regions caused by ice shedding become difficult, showing an unstable propagating path, indeterminate arc shape and longer arc column. Although VMF under ice shedding conditions is higher than that without ice shedding, the fundamental component, and harmonics show lower amplitudes for the latter case. The ratios of harmonics to the fundamental are well in accordance with discharge characteristics during the flashover for which the ratios show a relatively stable varying tendency in the absence of ice shedding, but show changeable and indeterminate variation under ice shedding conditions. The obtained results are helpful to understand the icing state and its influence on surface discharges for preventing the icing flashovers.

Analysis of queue discharge characteristics at signalized intersections is a primary component of traffic signal analysis and design. On the basis of previous studies, mainly conducted in homogeneous traffic conditions, the discharge headway is assumed to be high at the start of green for the first few vehicles, mainly because of start-up lost times, and is also assumed to reach the minimum value by the fourth or fifth vehicle in the queue. The minimum headway is expected to continue until the end of the queue. However, this may not be the case under heterogeneous traffic conditions, such as those in India, which has the additional problem of lacking lane discipline. Most of the signals in India include a countdown timer that indicates the time left for the signal phase, which is also expected to affect queue discharge characteristics. This paper presents insights gained on queue discharge characteristics at signalized intersections under heterogeneous traffic conditions and on the effect of a countdown timer on the headway distribution. The analysis was carried out using data collected from two intersections, one with a timer and one without, in Chennai, India, through the use of a videographic technique. The data collected are classified into three discharge regimes: start-queue, mid-queue, and end-queue. Linear regression models are used to assess the impact of vehicle types on queue discharge characteristics. The results indicate that the accepted headway distribution is followed when there is no timer. However, with the presence of a timer, there is a clear change in the trend for reduced start-up lost time and end lost time.

Показано влияние резки на скос кромок, структуру, твердость и деформации металла в зоне резки., Показано вплив різання на скіс кромок, структуру, твердість і деформації металу в зоні різання., Was show influencing of cutting on the edge develing, structure, hardness and deformations of metal in area of cutting.

In this work a flow stabilized corona torch plasma was used for periodic domain inversion of MgO-doped lithium niobate with 19 .1 μm periodic gratings. The effective non-linear coefficient (derr) achieved through corona discharge poling was 17.5 pm/V, which agrees well with theoretical value of 16~19 pm/V. By analysing the second harmonic generation (SHG) tuning curves, the grating uniformity over the 10 mm grating was investigated. The 0.6 run bandwidth of the SHG tuning at full width half maximum (FWHM) corresponded exactly to the theoretical value. The agreement between experimental data and theoretical results imply that the obtained periodically poled lithium niobate (PPLN) has high quality. By controlling temperature in the range of 20 °C to 120 °C tunability of SHG wavelength was demonstrated between 782 run and 788 run. Discharge characteristics of the corona were studied using a floating potential double probe and optical emission spectroscopy. Using the double probe the distribution of ion density downstream of the corona torch was observed. The maximum ion density of 2 x 1018 (ions/cm3) was achieved 2 mm below the discharge electrode. Measurement of the optical emission spectrum was used to determine the vibrational ion temperature to be 3953 K. The observed spectrum consisted entirely of the second positive band of nitrogen. The applied voltage range of 9 kV to 10 kV was observed to be optimum for domain growth in periodic poling. Poling uniformity of the 12 mm grating was optimized for an electrode to crystal spacing of 13 mm. Increasing the crystal temperature during poling reduces the required coercive field for domain inversion. This reduces the required applied voltage and also reduces the required poling time by increasing the domain-switching rate. Proton exchange pretreatment of the (+z) crystal surface prior to poling has been demonstrated to control domain spreading, however future efforts are required to ensure a more reliable nucleation condition. Both high vacuum and spin coated photoresist function to increase electrical discrimination of anode grating and provide an improved nucleation condition for periodic poling of MgO-doped lithium niobate. Poling uniformity of the 12 mm grating was optimised for an electrode to crystal spacing of 13mm. Thesis Master of Applied Science (MASc)

The measurement of power and current is very important to study discharge characteristics of dielectric barrier discharge (DBD). In order to analyze the effect of measure elements on discharge characteristics of DBD, three different resistors and capacitors are used for measuring discharge current and power, respectively. The resistance values of the resistors are 5.1 Ω, 15 Ω and 56 Ω. The capacitances of the capacitors are 2.2 nF, 22 nF and 150 nF. The experiments are carried out in a stainless mesh electrode DBD system. The discharge characteristics are obtained by using Lissajous figures and the discharge current. The results show that smaller capacitance and bigger resistance are suitable for obtaining the perfect lissajous and discharge current due to their improving the stability of DBD.