• Asian-Australasian Journal of Animal Sciences
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• v.20 no.2
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• pp.273-282
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• 2007

This study was carried out to compare the changes of nutrients, sensory and chemical properties of freeze-concentrated and evaporated milks during storage. For pasteurization, the freeze-concentrated milk containing 27% of total solid was treated with 150 rpm ozone for 5 min, and 99% of microflora was eliminated. Also, the activities of protease and lipase decreased 93.31% and 96.15%, respectively, and phosphatase showed negative activity. Total bacteria count was maintained below$2.0{\times}10^4$CFU/ml. During storage, TBA absorbance was lower in freeze-concentrated milk than that in the evaporated milk. The production of short-chain free fatty acids and free amino acids increased proportionally to the storage period in both samples. While the short-chain free fatty acid production was lower in the freeze-concentrated milk compared with that in the evaporated milk, the production of individual free amino acid was similar in both samples. In sensory evaluation, cooked flavor and color were much lower in the freeze-concentrated milk than that in the evaporated milk. Overall acceptability score was higher in the freeze-concentrated than the evaporated milk. Based on above results, ozone treatment for the freeze-concentrated milk pasteurization was positive at the elimination of microflora and enzyme inactivation. During storage, the freeze-concentrated sample minimized the change of color and TBA absorbance, the production of short-chain free fatty acid and vitamins than the evaporated milk. Therefore, the freeze-concentrated milk process in the present study resulted in the positive effect in minimizing nutrient loss and keeping quality of milk during storage.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2005.11a
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• pp.75-76
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• 2005

• Proceedings of the KSRS Conference
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• 2004.10a
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• pp.182-183
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• 2004

Atmospheric carbon monoxide (CO) and ozone $(O_3)$ play the important trace gases in tropospheric chemistry, through its concentration in the troposphere directly influences the concentrations of tropospheric hydroxyl (OH). Understanding the impact of CO and $O_3$ on the global tropospheric chemistry requires measurements of the global atmospheric CO and $O_3$ distributions. This study focuses on the identification of CO and O3 released in the East Asia between March 2000 and February 2004. During the period, the MOPITT instrument onboard the Earth Observing System (EOS)-Terra platform collected extensive measurement of CO. So we have used MOPITT data at 700hPa to analyze seasonal distribution of CO concentration. And the O3 measurements for this study were Total Ozone Mapping Spectrometer (TOMS) and Dobson spectrometer provided NASA/GSFC and Yonsei University, Korea. During springtime, the CO and O3 concentrations were increased over East Asia for April, May, and June. CO and O3 transport and chemistry in the springtime in East Asia are studied by use of the HYbrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model.

• Bulletin of the Korean Space Science Society
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• 2004.10b
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• pp.372-375
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• 2004

The UV radiometer payload was launched successfully from the west coastal area of Korea Peninsula aboard KSR-III on 28, Nov 2002. KSR-III was the Korean third generation sounding rocket and was developed as intermediate step to larger space launch vehicle with liquid propulsion engine system. UV radiometer onboard KSR-III consists of UV and visible band optical phototubes to measure the direct solar attenuation during rocket ascending phase. For UV detection, 4 channel of sensors were installed in electronics payload section and each channel has 255, 290, 310nm center wavelengths, respectively. 450nm channel was used as reference for correction of the rocket attitude during the flight. Transmission characteristics of all channels were calibrated precisely prior to the flight test at the Optical Lab. in KARI (Korea Aerospace Research Institute). During a total of 231s flight time, the onboard data telemetered to the ground station in real time. The ozone column density was calculated by this telemetry raw data. From the calculated column density, the vertical ozone profile over Korea Peninsula was obtained with sensor calibration data. Our results had reasonable agreements compared with various observations such as ground Umkhr measurement at Yonsei site, ozonesonde at Pohang site, and satellite measurements of HALOE and POAM. The sensitivity analysis of retrieval algorithm for parameters was performed and it was provided that significant error sources of the retrieval algorithm.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.5
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• pp.1319-1328
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• 2016

Since Ballast Water Management Convention has been effected, BWTS, applied to new-building vessels and existing vessels, have been developed from many countries with various treatment methods. However, BWTS is mainly typed Electrolysis, Ozone and UV type. Approximately 70 products have been type approved by the Flag Administrations. For the new-building vessels, the vessels' design and construction have been considered for arrangements and installations for BWTS. However, existing vessels which already construction had finished have problem with selection of BWTS type for installation and arrangement. The selection of the most economized BWTS system is important though, CAPEX has not been made any significant differences. However, OPEX is more important factor. Consequently, detail analysis of OPEX is the key to the selection of the most economized BWTS system and also it can be the purpose of this study. The feasibility study on the main three type of BWTS (Electrolysis, Ozone and UV type) for 175K Bulk Carrier and 57K Cargo ship has been conducted for this study. Because, these three type of BWTS have been the most frequently installed and used and the two type of object vessels are consist of the 40% of the world merchant ship market. For this study, interest rate, project duration (operation time after installation), maintenance cost and fuel oil price are considered as major factor of feasibility study. In addition, expecting Interest rates to sensitivity analysis conducted for more accurate feasibility study. For 175K Bulk carrier, ozone treatment system is more economical than other types. For 57K cargo ship, UV type is considered more economical than other types. However, it is concluded that electrolysis type is more suitable compare to installation space, total weight and electrical power consumption.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.6
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• pp.688-696
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• 2018

This study investigated the effects of ozone-produced oxidants (OPO) on the growth, hematology, and histology of olive flounder Paralichthys olivaceus (average weight 500 g), raised in an ozonated semi-recirculating aquaculture system. The system was ozonated to maintained OPO concentrations of 0.004 (Control), 0.014 (OPO15), and 0.025 (OPO25) mg $Cl_2/L$ in culture tanksfor 26 days. The specific growth rate, feed conversion ratio, and survival rate did not significantly differ among the groups (P>0.05), while the daily feeding rate decreased OPO-dose-dependently (P<0.05). OPO appeared to affect the gill, hepatopancreas, and kidney tissues of fish from ozonated tanks. Hematologically, OPO affected some blood indices. The levels of chloride, glucose, glutamic oxaloacetic transaminase, and glutamic pyruvic transaminase were significantly increased in the ozonated groups, while the total cholesterol and cortisol decreased dose-dependently. These results imply that long-term exposure of olive flounder to an OPO concentration ${\geq}0.014mg\;Cl_2/L$ might result in damage to the gill, hepatopancreas, and kidney tissues and cause physiological stress, albeit with no apparent short-term effects on growth or survival.

• International Journal of Aeronautical and Space Sciences
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• v.14 no.2
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• pp.193-199
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• 2013

This work investigates the orbital perturbations of the cubesats that lie on LEO due to Earth albedo. The motivation for this paper originated in the investigation of the orbital perturbations for closed- Earth pico-satellites due to the sunlight reflected by the Earth (the albedo). Having assumed that the Sun lies on the equator, the albedo irradiance is calculated using a numerical model in which irradiance depends on the geographical latitude, longitude and altitude of the satellite. However, in the present work the longitude dependency is disregarded. Albedo force and acceleration components are formulated using a detailed model in a geocentric equatorial system in which the Earth is an oblate spheroid. Lagrange planetary equations in its Gaussian form are used to analyze the orbital changes when $e{\neq}0$ and $i{\neq}0$. Based on the Earth's reflectivity data measured by NASA Total Ozone Mapping Spectrometer (TOMS project), the orbital perturbations are calculated for some cubesats. The outcome of the numerical test shows that the albedo force has a significant contribution on the orbital perturbations of the pico-satellite which can affect the satellite life time.

• Journal of Korean Society for Atmospheric Environment
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• v.24 no.E2
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• pp.74-82
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• 2008

We have examined seasonal and annual means of clear-sky solar noon and daily erythemal ultraviolet-B irradiances measured in Anmyeon. The intensity of the EUV-B irradiance is mainly dependent on solar zenith angle (SZA) and total ozone amounts on clear day conditions. The daily maximum occurs near solar noon time and the highest monthly accumulated EUV-B is seen in July in Anmyeon. The maximum daily variation occurs in June and July due to precipitation and clouds. The 7-year trend of EUV-B irradiance shows that it is slightly increasing. Additionally, we could confirm that aerosol effects such as Asian Dust decreases the EUV-B irradiance reaching the ground surface by 35% to 60%. For more than 45% of the summer days, EUV-B irradiacne was high enough that the UV index registered higher than category Extremely High. This information will be very important for evaluation of the UV index for prevention of both skin cancer and ecosystem damages as well as to understand UV climatology over the Korean Peninsula.

• Journal of Korean Society for Atmospheric Environment
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• v.20 no.6
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• pp.759-771
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• 2004

This study analyzed concentrations of volatile organic compounds (VOCs) produced from incineration of plastic wastes at $600^{\circ}C$. The plastic wastes used in this study included polyethyleneterephthlate (PETE), high density polyethylene (HOPE), polyvinyl chloride (PVC), low density polyethylene (LOPE), polypropylene (PP), polystyrene (PS) and other. Plastic wastes were heated from room temperature upto $600^{\circ}C$ providing the compressed air inside of a small-scale electric furnace for 90 minutes and then they were oxidized (incinerated) for 60 minutes at $600^{\circ}C$ maintaining the same air supply. VOCs emitted from the incineration process were sampled using an air sampling pump and Tedlar air bags for 150 minutes and then the components and concentrations of the VOCs were analyzed by a GC-MS. The most prominent chemical structure of the VOCs obtained from the incineration process of the HOPE, LOPE and PP, which include ethylene groups in their main chains, was identified as aliphatic hydrocarbons such as 1-hexene. However, aromatics such as benzene were major chemical structure from the incineration of PETE, PVC and PS which include benzene rings in their main chains. This study estimated the total VOC production from the incineration of the plastic wastes based on the real plastic waste production and the emission factors. 64% and 27% of the total VOC emissions consisted of aliphatic hydrocarbons and aromatics, respectively, which have double bonds within their molecular structure and thus a high ground level ozone formation potential.

• Journal of Korean Society for Atmospheric Environment
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• v.34 no.3
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• pp.457-468
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• 2018

To improve understanding of the physico-chemical characteristics of aerosols in the national park and comparing the air pollution between national park and the urban area nearby national park, the aerosol characterization study was conducted in Bukhansan National Park, Seoul, from July through September 2017. Semi-continuous measurements of $PM_{2.5}$ using PILS (Particle Into Liquid System) coupled with IC (Ion Chromatography) and TOC (Total Organic Carbon) analyzer allowed quantification of concentrations of major ionic species($Cl^-$, $SO_4{^{2-}}$, $NO_3{^-}$, $Na^+$, $NH_4{^+}$, $K^+$, $Mg{^{2+}}$ and $Ca{^{2+}}$) and water soluble organic carbon (WSOC) with 30-minute time resolution. The total mass concentration of $PM_{2.5}$ was measured by T640 (Teledyne) with 5-minute time resolution. The black carbon (BC) and ozone were measured with a minute time resolution. The timeline of aerosol chemical compositions reveals a strong influence from urban area (Seoul) at the site in Bukhansan National Park. Inorganic aerosol composition was observed to be dominated by ammoniated sulfate at most times with ranging from $0.1{\sim}32.6{\mu}g/m^3$ (6.5~76.1% of total mass of $PM_{2.5}$). The concentration of ammonium nitrate, a potential indicator of the presence of local source, ranged from below detection limits to $20{\mu}g/m^3$ and was observed to be highest during times of maximum local urban (Seoul) impact. The total mass of $PM_{2.5}$ in Bukhansan National Park was observed to be 10~23% lower than the total mass of $PM_{2.5}$ in urban area (Gireum-dong and Bulgwang-dong, Seoul). In general, ozone concentration in Bukhansan National Park was observed to be similar or higher than urban sites in Seoul, suggesting additional biogenic VOCs with $NO_x$ from vehicle emission were to be precursors for ozone formation in Bukhansan National Park.