• Title/Summary/Keyword: Corona product

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The Changes of Consumption Behavior in Bengkulu, Indonesia: Case of Purchasing Corona Prevention Products Through Indirect Ditribution Channel

  • Hayu, Rina Suthia;Sulistiyawan, Edy;Salim, Muhartini
    • Journal of Distribution Science
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    • v.19 no.11
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    • pp.27-36
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    • 2021
  • Purpose: COVID-19, government regulation and social media have changed many aspects of life including consumption behavior. The influence of social media by spreading massive news about COVID-19 also have the impact toward emotions threat, perceived risk, and perceived value of consumption behavior in Bengkulu Province, Indonesia. This research aims to analyze the extent to which changes in the consumption behavior, mainly for purchasing of corona prevention products through indirect distribution channels. Research design, data and methodology: This research was descriptive quantitative using the IPA method with sample of people in Bengkulu Province. This study obtained 208 respondent data from questionnaires and tested the validity and reliability with corrected-item total correlation method. Results: The study found that COVID-19 pandemic and government regulation variable were in quadrant II, in quadrant III there were social media variable, emotions threat and perceived risk. Meanwhile, in quadrant IV there were perceived value variable. Conclusions: The findings indicated that COVID-19 and government regulation are the most variable that influence people to buy corona prevention product, meanwhile perceived value is the less influence variable. Therefore, government and marketers have to prepare strategic plan in order to raise people awareness to avoid corona by buying corona prevention product.

Design and Performance Evaluation of a Diode Type Corona Charger for Real-Time Measurement of the Submicron Aerosol (실시간 미세입자 측정을 위한 다이오드형 코로나 하전기의 설계 및 성능평가)

  • Cho, Myung-Hoon;Ji, Jun-Ho;Park, Dong-Ho;Bae, Gwi-Nam;Hwang, Jung-Ho
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.28 no.9
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    • pp.1066-1074
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    • 2004
  • With a diode corona charger, which is a component of ELPI(Electrical Low Pressure Impactor), aerosol particles are charged to make electrical detection possible before they are collected by the impactor. We designed and evaluated two cylindrical corona chargers, each of which had a central corona needle electrode. For the performance evaluation of each corona charger the polydisperse dioctyl sebacate(DOS) particles, with diameters of 0.1∼0.8 $\mu$m and NaCl particles, smaller than 0.1$\mu$m, were used. The particles were then led through an electrostatic classifier (TSI model 3081) to classify monodisperse aerosol with minimal size deviation. After evaluating the wall loss of the particles in the corona charger, we measured the product of penetration and number of charges, Pㆍn, to evaluate the corona charger efficiency at high positive voltages of 4, 5, 6 kV.

On the Metric Dimension of Corona Product of a Graph with K1

  • Mohsen Jannesari
    • Kyungpook Mathematical Journal
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    • v.63 no.1
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    • pp.123-129
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    • 2023
  • For an ordered set W = {w1, w2, . . . , wk} of vertices and a vertex v in a connected graph G, the k-vector r(v|W) = (d(v, w1), d(v, w2), . . . , d(v, wk)) is called the metric representation of v with respect to W, where d(x, y) is the distance between the vertices x and y. A set W is called a resolving set for G if distinct vertices of G have distinct metric representations with respect to W. The minimum cardinality of a resolving set for G is its metric dimension dim(G), and a resolving set of minimum cardinality is a basis of G. The corona product, G ⊙ H of graphs G and H is obtained by taking one copy of G and n(G) copies of H, and by joining each vertex of the ith copy of H to the ith vertex of G. In this paper, we obtain bounds for dim(G ⊙ K1), characterize all graphs G with dim(G ⊙ K1) = dim(G), and prove that dim(G ⊙ K1) = n - 1 if and only if G is the complete graph Kn or the star graph K1,n-1.

Spectroscopic Identification of Isomeric Trimethylbenzyl Radicals Generated from 1,2,3,4-Tetramethylbenzene

  • Yoon, Young-Wook;Lee, Sang-Kuk
    • Bulletin of the Korean Chemical Society
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    • v.32 no.8
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    • pp.2751-2755
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    • 2011
  • The visible vibronic emission spectrum was recorded from the corona discharge of precursor 1,2,3,4-tetramethylbenzene with a large amount of inert carrier gas helium using a pinhole-type glass nozzle coupled with corona excited supersonic expansion. The spectrum showed a series of vibronic bands in the $D_1{\rightarrow}D_0$ electronic transition of jet-cooled benzyl-type radicals formed from the precursor in a corona excitation. The analysis confirmed that two isomeric radicals, 2,3,4- and 2,3,6-trimethylbenzyl radicals, were produced as a result of removal of a hydrogen atom from the methyl group at different substitution positions. For each isomeric product, the electronic transition and a few vibrational mode frequencies were determined in the ground electronic state.

Rearrangement of Benzyl-type Radical in Corona Discharge of 2,6-Dichlorotoluene

  • Yoon, Young-Wook;Lee, Seung-Woon;Lee, Sang-Kuk
    • Bulletin of the Korean Chemical Society
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    • v.31 no.9
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    • pp.2479-2482
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    • 2010
  • Using a pinhole-type glass nozzle equipped for a corona-excited supersonic expansion (CESE), precursor 2,6-dichlorotoluene seeded in a large amount of inert carrier gas helium was discharged to produce jet-cooled but electronically excited benzyl-type radicals. The visible vibronic emission spectrum was recorded with a long-path monochromator to observe vibronic bands in the $D_1{\rightarrow}D_0$ electronic transition of benzyl-type radicals. The spectral analysis revealed the generation of not only the 2,6-dichlorobenzyl radical as a typical product, but also the o-chlorobenzyl radical as an unexpected species, which indicates the possible molecular rearrangement in eliminating a chlorine atom from the benzene ring. A possible mechanism is proposed for the formation of the o-chlorobenzyl radical from the precurs or in the gas phase.

Approach to Characterization of a Diode Type Corona Charger for Aerosol Size Measurement

  • Intra Panich;Tippayawong Nakorn
    • KIEE International Transactions on Electrophysics and Applications
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    • v.5C no.5
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    • pp.196-203
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    • 2005
  • A semi-empirical method to determine the electrostatic characteristics of a diode type corona aerosol charger based on ion current measurement and electrostatic charging theory was presented. Results from mathematical model were in agreement with those from experimental investigation of the charger. Current-voltage characteristics, $N_{i}t$ product and charge distribution against aerosol size were obtained. It was shown that the space charge was significant and must be taken into account at high ion number concentration and low flow rate. Additionally, significant particle loss was evident for particles smaller than 20 nm in diameter where their electrical mobility was high. Increase in charging efficiency may be achieved by introducing surrounding sheath flow and applying AC high voltage. Overall, the approach was found to be useful in characterizing the aerosol charger.

Corona Discharge Characteristics and Particle Losses in a Unipolar Corona-needle Charger Obtained through Numerical and Experimental Studies

  • Intra, Panich;Yawootti, Artit;Rattanadecho, Phadungsak
    • Journal of Electrical Engineering and Technology
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    • v.12 no.5
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    • pp.2021-2030
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    • 2017
  • In this paper, the unipolar corona-needle charger was developed and its capabilities were both numerically and experimentally investigated. The experimental corona discharges and particle losses in the charger were obtained at different corona voltage, aerosol flow rate and particle diameter for positive and negative coronas. Inside the charger, the electric field and charge distribution and the transport behavior of the charged particle were predicted by a numerical simulation. The experimental results yielded the highest ion number concentrations of about $1.087{\times}10^{15}ions/m^3$ for a positive corona voltage of about 3.2 kV, and $1.247{\times}10^{16}ions/m^3$ for a negative corona voltage of about 2.9 kV, and the highest $N_it$ product for positive and negative coronas was found to about $7.53{\times}10^{13}$ and $8.65{\times}10^{14}ions/m^3$ s was occurred at the positive and negative corona voltages of about 3.2 and 2.9 kV, respectively, and the flow rate of 0.3 L/min. The highest diffusion loss was found to occur at particles with diameter of 30 nm to be about 62.50 and 19.33 % for the aerosol flow rate of 0.3 and 1.5 L/min, respectively, and the highest electrostatic loss was found to occur at particles with diameters of 75 and 50 nm to be about 86.29 and 72.92 % for positive and negative corona voltages of about 2.9 and 2.5 kV, respectively. The numerical results for the electric field distribution and the charged particles migration inside the charger were used to guide the description of the electric field and the behavior of charged particle trajectories to improve the design and refinement of a unipolar corona-needle charger that otherwise could not be seen from the experimental data.

Popularization of Autonomous Vehicles and Arbitrability of Defects in Manufacturing Products (자율주행차의 대중화와 제조물하자에 관한 중재가능성)

  • Kim, Eun-Bin;Ha, Choong-Lyong;Kim, Eung-Kyu
    • Journal of Arbitration Studies
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    • v.31 no.4
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    • pp.119-136
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    • 2021
  • Due to the restriction of movement caused by the Corona epidemic and the expansion of the "big face" through human distance, the "unmanned system" based on artificial intelligence and the Internet of Things has been widely used in modern life. "Self-driving," one of the transportation systems based on artificial technology, has taken the initiative in the transportation system as the spread of Corona has begun. Self-driving technology eliminates unnecessary contact and saves time and manpower, which can significantly impact current and future transportation. Accidents may occur, however, due to the performance of self-driving technology during transportation albeit the U.S. allows ordinary people to drive automatically through experimental operations, and the product liability law will resolve the dispute. Self-driving has become popular in the U.S. after the experimental stage, and in the event of a self-driving accident, product liability should be applied to protect drivers from complicated self-driving disputes. The purpose of this paper is to investigate whether disputes caused by defects in ordinary cars can be resolved through arbitration through U.S. precedents and to investigate whether disputes caused by defects in autonomous cars can be arbitrated.

A Study on the Energy Efficiency for NO Removal by Pulsed Corona Discharge (펄스 코로나 방전을 이용한 NO제거 에너지 효율에 대한 연구)

  • Kang, Hun;Song, Bong-Shik;Lee, Seok-Hyun;Doh, Hyun-Ho;Kim, Youn-Teag
    • Proceedings of the KIEE Conference
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    • 1999.07e
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    • pp.2010-2012
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    • 1999
  • The product of electrons by Pulsed Corona Discharge leads to produce radicals which work on NO, and NO is finally removed. Energy efficiency for NO removal was improved with increasing peak voltage rather than with increasing pulse frequency. The rate of energy transfer increased with decreasing value of $C_p$( Pulse - Forming Capacitance 2.15, 1.06, 0.55, 0.36, 0.1[nF]. When the value of $C_p$ reached to 0.36 [nF], the energy efficiency for NO removal was maximized. And good agreement was obtained between chemical kinetic calculations and the experimental results.

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Design and Evaluation of a High Concentration, High Penetration Unipolar Corona Ionizer for Electrostatic Discharge and Aerosol Charging

  • Intra, Panich;Tippayawong, Nakorn
    • Journal of Electrical Engineering and Technology
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    • v.8 no.5
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    • pp.1175-1181
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    • 2013
  • The aim of this paper is to design and evaluate a high concentration, high penetration unipolar corona ionizer. The electrostatic characteristics in terms of voltage-current relationships of the present ionizer in the discharge zones for positive and negative coronas were discussed. Using ion current measurement, the concentration and penetration of ions were evaluated at corona voltages across the needle electrodes between 1 and 4 kV, flow rates between 1 and 5 L/min, and an operating pressure of 1 atm. In the discharge zone of the ionizer, the highest ion concentrations were found to be about $1.71{\times}10^{14}$ and $5.09{\times}10^{14}\;ions/m^3$ for positive and negative coronas, respectively. At the outlet of the ionizer, it was found that the highest ion concentration was about $1.95{\times}10^{13}$ and $1.91{\times}10^{13}\;ions/m^3$ for positive and negative coronas, respectively. The highest ion penetration for positive and negative coronas through the ionizer was found to be about 98 % and 33 %, respectively. The $N_it$ product for positive and negative coronas was also found to $1.28{\times}10^{13}$ and $7.43{\times}10^{13}\;ions/m^3s$, respectively. From the findings, this ionizer proved to be particularly useful as an aerosol charger for positive and negative charge before the detector in an electrical aerosol detector.