• Atmosphere
• /
• v.15 no.3
• /
• pp.149-153
• /
• 2005

A balloon-borne Optical Particle Counter (hereafter "OPC Sonde"), which was developed by the atmospheric research group of Nagoya University, is used for getting the information of vertical profile of particle size and concentration in Anmyeon ($36^{\circ}32^{\prime}N$ $126^{\circ}19^{\prime}E$) on 18 March 2005. A range of five different particle sizes is shown in the vertical profile of aerosol number density estimated from the OPC Sonde. It was found that small size particles have vertically larger aerosol number density than relatively big ones. For all size ranges the vertical aerosol number density shows a decreased pattern as the altitude becomes higher. The aerosol number density of $0.3{\sim}0.5{\mu}m$, $0.5{\sim}0.8{\mu}m$, $0.8{\sim}1.2{\mu}m$ size ranges at the 10km height, which is the tropopause approximately, are $1,000,000ea/m^3$, $100,000ea/m^3$, $10,000ea/m^3$ respectively. The data of OPC Sonde are also compared with the data of PM10 $\beta$-ray) and Micro Pulse Lidar which are operating at Korea Global Atmosphere Watch Observatory in Anmyeon.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.51 no.3
• /
• pp.185-193
• /
• 2014

In this paper, we developed a 4-channel particle counter for measuring particles, temperature, humidity in production facilities of clean-room environment, and the measured data can be transmitted via bluetooth. To measure the particle size ranging 0.3um~5um, we designed optical lens, particle detection chamber and multi-channel particle detection circuit. And we also developed a FMS program for real-time monitoring of measuring data, which resulted in the stable operation.

• Proceedings of the Optical Society of Korea Conference
• /
• 2004.07a
• /
• pp.280-281
• /
• 2004

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.13 no.9
• /
• pp.4334-4340
• /
• 2012

In this work, we developed and evaluated the Liquid Particle Generator for generating fine particles in the air. The Liquid Particle Generator, which was based on the spray-evaporation method, had two kinds of orifices: 0.3 mm and 0.5 mm. The Liquid Particle Generator was operated at different pressure between 1 bar and 4 bars to find relationship between input pressure and droplet output rate. In addition, the size distribution of the droplets generated by the Liquid Particle Generator with different orifices was measured by the SMPS system and the optical particle counter. As a result, it was shown that the Liquid Particle Generator with 0.3 mm orifice generated droplets of around 0.3 ${\mu}m$ and atomized particles very stably. The Liquid Particle Generator having 0.5 mm orifice generated bigger droplets, compared with the Liquid Particle Generator with 0.3 mm orifice. Additionally, in these Liquid Particle Generators (0.3 mm and 0.5 mm orifice), little coagulation of particles did occur because of fine droplets atomized by the jet. Therefore, the Liquid Particle Generator could be used as an aerosol generator for atomizing fine particles.

• Journal of Korean Society for Atmospheric Environment
• /
• v.32 no.1
• /
• pp.1-8
• /
• 2016

Optical particle sizer (OPS), optical particle counter (OPC), and aethalomter were deployed to measure the particle number concentrations from 0.3 to $10.0{\mu}m$ and black carbon (BC) concentrations. Comparisons of particle number concentrations measured by OPS and OPC were conducted to evaluate the performance of the each optical instrument at the Gwangju sampling site ($35.23^{\circ}N$, $126.84^{\circ}E$) for 14 days from Dec. 27 in 2014. Although a good correlation ($r^2=0.99$) between the OPS and OPC was observed for both the particle number and volume concentrations, different relationships by BC concentrations can be associated with the intensities by different light scattering angles. In addition, based on diurnal patterns of size distributions in 24 hr running correlation coefficient determination, BC concentrations were highly related to the particles less than $0.3{\mu}m$ observed in the morning traffic hour.

• Particle and aerosol research
• /
• v.16 no.2
• /
• pp.49-59
• /
• 2020

Various devices have been developed to the measurement of particulate matter pollutants, and Optical Particle Counter (OPC) that can be easily and quickly measured is widely used lately. The measured value by OPC is converted to weight concentration using the correction factor (CF). The calculation of CF is very important to improve the reliability and accuracy of OPC. In this study, the CF calculation study of light scattering laser photometer (model 8533, TSI) was carried out to measure in the atmospheric environment using 2 gravimetric devices and 3 light scattering laser photometer devices. Regression analysis and Tukey tests were used to significance the test of measurement devices. Measurements were carried out twice. There was a comparative analysis of measurement data between light scattering laser photometer and gravimetric devices in 1st measurement, and then the Evaluation of PM2.5 concentration corrected by CF performed in 2nd measurement. As a result of the significance analysis between light scattering laser photometer and gravimetric devices, the correlation between the same method was high, but the correlation between different methods was low. CF was calculated as 0.4258 based on the measurement results, and it is a similar level to previous studies at home and abroad. It is expected that these results can be used as basic data in the future study for air quality measurement research using light scattering laser photometer. Also, in order to improve the accuracy of the measurement techniques and the development of technology in the atmospheric environment, CF calculation research should be conducted continuously.

• Particle and aerosol research
• /
• v.19 no.4
• /
• pp.155-164
• /
• 2023

APS (Aerodynamic Particle Sizer) and OPC (Optical Particle Counter) have been widely used to real-time measurement of indoor and outdoor aerosols. The APS measures the size distribution based on an aerodynamic diameter, while the OPC uses optical diameter to measure the size distribution of aerosols. Since obtaining a size distribution based on aerodynamic diameter is important to understand aerosol characteristics, lots of researcher had been developed experimental equations which can convert optical diameter into aerodynamic diameter. However, previous studies have conducted repeated experiments on particles having a single diameter. In this study, an experimental method of converting optical diameter into aerodynamic diameter through a single experiment was presented. The collection efficiencies of an axial cyclone were measured using APS and OPC at the same time, and the correlation equation between aerodynamic diameter and optical diameter was driven through a theoretical model. Using the proposed method, the size distribution of NaCl particles measured by OPC showed a high correlation with the size distribution obtained by APS (0.93 of R-squared value). In the tests conducted on ISO A1, A2, and A4 test particles, the converted OPC size distribution tended to be similar to the APS size distribution, and for each of test particles (ISO A1, A2, and A4), the R-squared values for the APS particle size distribution were 0.75, 0.86, and 0.89, respectively.

• Proceedings of the Korea Air Pollution Research Association Conference
• /
• 1999.10a
• /
• pp.83-84
• /
• 1999

시정악화나 광화학 스모그를 비롯하여 지구 온난화에 부유 입자상 물질이 미치는 영향 등을 파악하기 위해선 중량농도, 화학적 성분분석 등과 함께 그 입경별 크기 분포도 반드시 고려되어야만 한다. 입경분포 측정을 위하여 다단식 임팩터(Cascade Impactor)나 광학입자계수기(OPC, Optical Particle Counter), Aerosizer, SMPS (Scanning Mobility Particle Sizer), EAA(Electrical Aerosol Analyzer) 등 이주로 사용되고 있다.(중략)

• Proceedings of the Korea Air Pollution Research Association Conference
• /
• 2002.11a
• /
• pp.314-315
• /
• 2002

대기중에는 다양한 크기와 모양, 그리고 화학성분을 가진 입자들이 존재한다. 이러한 입자들은 발생원이 다양하고 대기중에 존재하면서 광화학적인 변화를 거쳐 형성되기도 한다. 입자의 화학조성과 크기는 발생원을 구분하기 위한 일반적인 척도로 쓰이고 있다. 대기 에어러솔의 크기분포특성은 에어러솔의 변화 요소인 발생원과 제거 그리고 동역학적인 과정을 이해하는데 중요한 역할을 한다. (중략)

• Journal of The Korean Society of Agricultural Engineers
• /
• v.61 no.5
• /
• pp.79-87
• /
• 2019

With desires for safe food, there is growing concern that pesticide spray drift will expose people, plants, and the environment to pesticide residue and potential negative effects thereof. For highly efficient, safe spray application, technologies for measuring the spray drift should be developed and improved with some urgency. This study investigated the applicability of two optical particle counters (OPCs), which are mostly used to measure airborne particle mass concentration, for measurement of airborne pesticide spray drift. Experiments were conducted in a controlled laboratory and an ash tree orchard to evaluate the handiness and accuracy of two OPCs, OPC 1 and OPC 2. The experimental results indicated that the OPC 1 was better applicable to the measurement of spray drift in the field while the use of the OPC 2 was limited due to its narrow range of measurable droplet sizes. The readings of the OPC 1 produced highly accurate results ($R^2=0.9637$) compared to the actual spray drift. For better application of OPCs, this study suggests the OPCs should be positioned properly to inhale spray droplets of the appropriate size and concentration.