• Computers and Concrete
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• v.29 no.6
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• pp.361-374
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• 2022

On the premise of ensuring that the automatic and quantitative discharging function of concrete conveyors is met, the accuracy of the weight forecast by the mathematical model of the screw conveying volume is improved, and the error of the weight of the concrete parts and the accumulation thickness is reduced. In this paper, the discrete element method (DEM) is used to simulate the macroscopic flow of concrete. Using the concrete discrete element model, the size of the screw conveyor is set, and establish the response model between the influencing factors (process and structure) and the concrete mass flow rate according to the design points of the screw discharging experiment. The nonlinear data fitting method is used to obtain the volumetric efficiency function under the influence of process and structural factors, and the traditional screw conveying volume model is improved. The mass flow rate of concrete predicted by the improved mathematical model of screw conveying volume is consistent with the test results. The model can accurately describe the conveying process of concrete and achieve the purpose of improving the accuracy of forecasting the weight of discharged concrete.

• Journal of Korean Society of Water and Wastewater
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• v.18 no.4
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• pp.529-536
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• 2004

Innovated technique to inactivate microorganisms has been developed. This technique uses plasma discharge in 2-phase (Air-Water). Dielectric Barrier (two phase) Discharging system is able to produce new oxidants for microorganisms. Products from discharging are $HNO_2$, $NO_2{^-}$, $HNO_3$, $NO_3{^-}$ and ozone but many other radicals can be generated as well. DBD water has low concentration of ozone (about 0.5mg/L), $NO_2{^-}$, $NO_3{^-}$ (about 10mg-N/L, 20mg-N/L respectively) and lots of $H^+$. These products play an important role in oxidation. Oxidation power by KI titration methods is approximately equivalent to $50mg-O_3/L$. Surprisingly stored DBD water could oxidize KI and maintain stable pH (about pH3) even after several days. Stored DBD water for 5 days has also more than 4log disinfection power to E. coli. However, DBD water cannot be used for drinking water directly due to it's toxicity. Additional process to neutralize pH and decrease toxicity must be applied.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.39 no.7
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• pp.625-631
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• 2015

In this study, a numerical analysis on the discharging performance of a thermal storage tank completely filled with packing modules is investigated. The enthalpy-porosity method is adopted to analyze phase change phenomenon. Using this method, the melting process of a packing module in the thermal storage tank was studied as the HTF (heat transfer fluid) flows down from the top of the tank at the discharging mode. There are some design factors such as the module arrangement and the number of modules, but this study focuses on the effects of varying the flow rate of the HTF on the outlet temperature of the HTF, molten fraction, and thermal storage density. As the flow rate increases, the outlet temperature of the HTF gets higher and the total melting time of the PCM decreases. Additionally, the thermal storage density is increased so that it reaches about 93% for the desired value.

• Fire Science and Engineering
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• v.34 no.1
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• pp.66-71
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• 2020

The process of discharging batteries using salt water, when used for the disposal of a lithium-ion (Li-ion) batteries, is likely to cause a fire. However, there is a dearth of studies in the literature on the risk of fire while discharging mobile phone batteries in salt water. In order to investigate the possibility of fire by elucidating the discharge characteristics and the generation of heat, we conducted experiments by varying the concentration of the salt water, number of overlapping batteries, and type of the mobile phone batteries used as experimental specimen. The discharging voltage and the temperature of the batteries were measured, and the fire risk was predicted by analyzing the data. The results of the experiment showed that the higher the salt water concentration, the greater the discharge value of the mobile phone battery and the higher the exothermic temperature. Moreover, the exothermic temperatures of the overlapping batteries were higher than that of the single battery submerged in salt water. The highest exothermic temperature points of the battery occurred at the positive and negative poles.

• Journal of Power Electronics
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• v.12 no.1
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• pp.1-9
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• 2012

This study investigates an application of the Hamming network-dual extended Kalman filter (DEKF) based on pattern recognition for high accuracy state-of-charge (SOC)/capacity estimation and state-of-health (SOH) prediction at various temperatures. The averaged nine discharging/charging voltage-temperature (DCVT) patterns for ten fresh Li-Ion cells at experimental temperatures are measured as representative patterns, together with cell model parameters. Through statistical analysis, the Hamming network is applied to identify the representative pattern that matches most closely with the pattern of an arbitrary cell measured at any temperature. Based on temperature-checking process, model parameters for a representative DCVT pattern can then be applied to estimate SOC/capacity and to predict SOH of an arbitrary cell using the DEKF. This avoids the need for repeated parameter measuremet.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.9
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• pp.1306-1311
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• 2014

In this paper, effect of recharging power by using ESS(Energy Storage System) was investigated when ESS was applied to the train. The recharging power was analyzed and measured. Also, by applying ALVT algorithm, effective recharging and discharging were studied. By using this process, recharging and discharging of the super capacitor were improved which led to enhancing the use of recharging power from the urban Railway vehicles.

• Proceedings of the IEEK Conference
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• 2001.06b
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• pp.85-88
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• 2001

This paper suggests an improved switch architecture for the rechargeable battery protection IC. In the existing protection IC, charging and discharging switches composed of the CMOS transistor and the diode are external components. It is difficult to integrate the switches in a CMOS process due to the large chip-size overhead and inevitable parasitic effects. In this paper, we propose a new switch architecture of the MOSFET's 'diode connection' method. The performance and chip-size overhead are proved to be adequate for the fully integrated protection IC.

• Analytical Science and Technology
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• v.8 no.4
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• pp.603-610
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• 1995

The charge transfer rate in polypyrrole(PPy) electropolymerized within poly(acrylonitrile-co-butadiene)(PAB) was compared with that in PPy deposited Pt electrodes by using cyclic voltammetry, chronoamperometry, and chronopotentiometry in acetonitrile. For both electrodes anodic and cathodic peak currents were proportional to scan rates below 100 mV/sec, but to square root of scan rates beyond 200 mV/sec. The apparent diffusion coefficient of $ClO{_4}^-$ in the PPy/PAB composite is estimated to be 1.6 times larger than that in PPy. The PPy films composited within PAB layer showed higher anodic and cathodic currents and possessed faster charging-discharging process and larger capacity.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.20 no.3
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• pp.350-356
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• 2011

In this paper, we proposed the automatic cutting mechanism of the perforation pipes in an automobile muffler. This cutting mechanism makes continuous work possible, because it performs the batch work via the sequential operation of loading, feeding, cutting, and discharging. The proposed cutting mechanism consists of the frame unit, escape unit, turning unit, feeding unit, vision system, clamping unit, spindle/cutting unit and cooling unit. And, these mechanisms have been modularized through mechanical, dynamical and structural optimized design using the SMO (SimDesigner Motion) analysis module. Also, the virtual prototype was carried out using the 3-D CAD program. The cutting process cycle is performed in the order of loading, vision processing, feeding, clamping, cutting and discharging. And the cycle time for cutting one piece was designed to be completed in four seconds.

• Journal of the Korean Society of Safety
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• v.11 no.4
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• pp.79-83
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• 1996

In this study, in attempt to develop a new application technique of discharge plasma, we employed a kind of discharging method called SPCP ( short for Surface discharge induced Plasma Chemical Process). Applications of SPCP have been widely used for years. Compact ozonizers to deodorize household equipments like refrigerators we a part of such applications. We took advantages of the compactness and durability of the SPCP electrode to set up an experimental apparatus for decompositing vapor of aromatic hydrocarbons such as toluene, benzene and xylenes, which are major substances given off In painting or washing processes and aggravate working conditions. Results obtained from this study are summarized as follows. 1) Aromatic hydrocarbon vapors of up to 2,000ppm were almost thoroughly decomposed at the flow rate of 4ℓ/min or lower under the discharge with electric power of 400 Watts. 2) In dry air, as the decomposition progresses, tar-like substance deposits on the discharging areas, which deteriorated the decomposition rate in the end. This substance, however, was almost thoroughly removed by keeping discharge in dry air containing no solvent vapor.