• Fisheries and Aquatic Sciences
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• v.8 no.3
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• pp.142-150
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• 2005

The effects of photoperiod, temperature, and fish size on oxygen consumption (OC) in the black porgy Acanthopagrus schlegeli, a euryhaline marine teleost, were studied using a closed recirculating seawater system with a respiratory chamber. Fish reared in indoor recirculating seawater tanks were divided into two groups: small (15.7-55.8 g, mean 38.1$\pm$15.9 g) and large (108.7-238.8 g, mean 181.8$\pm$54.9 g) fish. The OC of the fish showed a clear diel rhythm, with higher values in the daytime and lower values at night, in accordance with light (09:00-20:59 h) and dark (21:00-08:59 h) cycles. The OC of the fish increased linearly with the water temperature. The OC was the highest at 10:00 h, one hour after the onset of daylight and was the lowest at 03:00 h, six hours after dusk. The average OC at $20^{\circ}C$ during the light period was as high as 219.8 mg $O_2$/kg/h in the small fish and 156.3 mg $O_2$/kg/h in the large fish, while during the dark period it was as low as 130.5 and 110.4 mg $O_2$/kg/h, respectively. The OC during the dark period, which showed limited variation, could be regarded as the resting OC, and was 107.6, 130.5, and 219.8 mg $O_2$/kg/h at 15, 20, and $25^{\circ}C$, respectively, in small fish, and 52.3, 110.4, and 171.0 mg $O_2$/kg/h in large fish. As the body weight of black porgy increased, the OC decreased exponentially and the relationship was expressed as OC=1,222.8$BW^{-0.567}$, OC=1,113.2$BW^{-0.448}$, and OC=1,495.3$BW^{-0.468}$ at 15, 20, and $25^{\circ}C$, respectively. At a fish density of 14.5 g/L at $20^{\circ}C$, black porgy had the highest OC per breath compared to fish at the same density at 15 or $25^{\circ}C$. This suggests that the black porgy responds to the stocking density (15 kg/$m^3$) and water temperature ($20^{\circ}C$) conditions commonly observed in intensive aquaculture with the deepest breath and the highest metabolic activity.

• Radiation Oncology Journal
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• v.19 no.3
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• pp.275-286
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• 2001

Purpose : To setup procedures of quality assurance (OA) for implementing intensity modulated radiation therapy (IMRT) clinically, report OA procedures peformed for one patient with prostate cancer. Materials and methods : $P^3IMRT$ (ADAC) and linear accelerator (Siemens) with multileaf collimator are used to implement IMRT. At first, the positional accuracy, reproducibility of MLC, and leaf transmission factor were evaluated. RTP commissioning was peformed again to consider small field effect. After RTP recommissioning, a test plan of a C-shaped PTV was made using 9 intensity modulated beams, and the calculated isocenter dose was compared with the measured one in solid water phantom. As a patient-specific IMRT QA, one patient with prostate cancer was planned using 6 beams of total 74 segmented fields. The same beams were used to recalculate dose in a solid water phantom. Dose of these beams were measured with a 0.015 cc micro-ionization chamber, a diode detector, films, and an array detector and compared with calculated one. Results : The positioning accuracy of MLC was about 1 mm, and the reproducibility was around 0.5 mm. For leaf transmission factor for 10 MV photon beams, interleaf leakage was measured $1.9\%$ and midleaf leakage $0.9\%$ relative to $10\times\;cm^2$ open filed. Penumbra measured with film, diode detector, microionization chamber, and conventional 0.125 cc chamber showed that $80\~20\%$ penumbra width measured with a 0.125 cc chamber was 2 mm larger than that of film, which means a 0.125 cc ionization chamber was unacceptable for measuring small field such like 0.5 cm beamlet. After RTP recommissioning, the discrepancy between the measured and calculated dose profile for a small field of $1\times1\;cm^2$ size was less than $2\%$. The isocenter dose of the test plan of C-shaped PTV was measured two times with micro-ionization chamber in solid phantom showed that the errors upto $12\%$ for individual beam, but total dose delivered were agreed with the calculated within $2\%$. The transverse dose distribution measured with EC-L film was agreed with the calculated one in general. The isocenter dose for the patient measured in solid phantom was agreed within $1.5\%$. On-axis dose profiles of each individual beam at the position of the central leaf measured with film and array detector were found that at out-of-the-field region, the calculated dose underestimates about $2\%$, at inside-the-field the measured one was agreed within $3\%$, except some position. Conclusion : It is necessary more tight quality control of MLC for IMRT relative to conventional large field treatment and to develop QA procedures to check intensity pattern more efficiently. At the conclusion, we did setup an appropriate QA procedures for IMRT by a series of verifications including the measurement of absolute dose at the isocenter with a micro-ionization chamber, film dosimetry for verifying intensity pattern, and another measurement with an array detector for comparing off-axis dose profile.

• Journal of the Korean Wood Science and Technology
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• v.35 no.2
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• pp.39-50
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• 2007

The purpose of this study was to investigate the physico-mechanical properties and characteristics on reduction of formaldehyde and total volatile organic compound (TVOC) emission from particleboard (PB) with added volcanic pozzolan. Pozzolan was added as a scavenger at the level of 1, 3, 5, and 10 wt.% of urea formaldehyde (UF) resin for PB manufacture. The moisture content, density, thickness swelling, water absorption and physical properties of PBs were examined. Three-point bending strength and internal bond strength were determined using a universal testing machine. Formaldehyde and TVOC were determined by desiccator and 20L small chamber methods. With increasing pozzolan content the physical and mechanical properties of the PBs were not significantly changed, but formaldehyde and TVOC emissions were decreased. Because pozzolan has a rough and irregular surface with porous form, it can be used as a scavenger for PBs at a content up to 10 wt.% without any detrimental effect on the physical and mechanical properties.

• Korean Journal of Weed Science
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• v.30 no.2
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• pp.153-163
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• 2010

This study was carried out to establish an improved bioassay system, whole-plant bioassay which is more effective in developing natural herbicides for foliar treatment such as herbicidal essential oils. Two bioassay systems using four weed species (Echinochloa crus-galli, Digitaria sanguinalis, Aeschynomene indica, and Abutilon theophrasti), spraying method and spotting method, were established. Spraying method is applicable if the amount of test compounds is enough, while spotting method is useful for the small amount of test compounds. The initial application rate was desirable at $2,500{\sim}5,000\;{\mu}g\;mL^{-1}$. Herbicidal activities were higher in the NOP treatment when compared to the Tween 20 treatment. To efficiently evaluate volatile compounds such as essential oils, if the compound-treated pots were incubated in dew chamber for about 10hrs, better results were obtained in the degree and stability of herbicidal responses. When the efficiency of bioassay systems established in this study was compared, the spraying method was minimized four times to the conventional method that has beed used for screening of synthetic compounds in KRICT. On the other hand, in the spotting method, screening for development of a natural herbicides was possible even in level of 1/100 test volume and 1/200 amounts of test compound compared to the spraying method.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.13 no.2
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• pp.140-146
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• 2008

Marine ecotoxicological standard method using fish larvae was established with the standard test species of Oryzias latipes(Japanese Medaka) and Paralichthys olivaceus(flounder) and with the 7 day $LC_{50}$ as endpoint. Test method referred to the USEPA(1994) with the replacement of test species found in the Korean water. Standard test species were selected in terms of the species supply and ecological importance in Korean waters. Japanese medaka can be reared with small tanks in the lab and has wide tolerance on salinity, and flounder eggs can be easily obtained from commercial fish hatcheries. General conditions for larval fish toxicity test are as follows. The possible salinity ranges for toxicity test were $0{\sim}35\;psu$ for medaka and >20 psu for flounder. Test type was designated as static non-renewal test if the dissolved oxygen in the test chamber does not fall below 4.0 mg/L. Ages of test species were selected as 7 days after hatched for medaka(about 5 mm TL) and 25 days for flounder(about 10 mm TL) because of the low natural mortality after these periods. Test can be accepted when the survival rates are over 80% in control. Also, species sensitivity on standard reference materials(copper, cadmium or zinc) must be provided with the toxicity test results.

• Journal of Sericultural and Entomological Science
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• v.51 no.2
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• pp.173-179
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• 2013

This study was investigation for primary bionomical characteristics, emergence rate of wintering type pupa and oviposition preference, of Papilio xuthus. The emergence rate of wintering type pupa stored at cold chamber($4{\pm}1^{\circ}C$) was 85%, after 10 months. The average emergence rate of wintering type pupa during storage was 89.6%, and the emergence periods were $7.9{\pm}1.9days$ in room temperature. Mating ratio in large oviposition room, $6,000{\times}6,000{\times}3,500$ mm($W{\times}L{\times}H$), was $86.7{\pm}5.8%$ higher than $63.3{\pm}15.3%$ in small room, $2,500{\times}3,000{\times}2,000$ mm($W{\times}L{\times}H$). But the number of eggs in the large room were $137.0{\pm}16.5$ fewer than $141.7{\pm}20.4$ in the small room. As a result of oviposition preference experiment on three different host plants, 10 mated female laid $141.7{\pm}27.8$ on the leaves of Phellodendron amurensew more than $67.7{\pm}20.6$ on Zanthoxylum schinifolium and $77.0{\pm}21.8$ on Citrus unshiu. The egg periods were $4.4{\pm}0.8$ days after oviposition, and the hatchability was 92.2% in $25^{\circ}C$ room condition. The larval period were $19.9{\pm}2.1$ days in the high temperature, long day condition($25^{\circ}C$, 14L : 10D). The headwidth of each developmental larval stage were $0.72{\pm}0.02$(1st), $1.19{\pm}0.02$(2nd), $1.65{\pm}0.05$(3rd), $2.43{\pm}0.07$(4th), $3.21{\pm}0.12$(5th). The pupal ratio was 91.6%. The pupal period were $8.8{\pm}0.9$ days, and the emergence rate was 92.2%.

• Journal of the Korean Wood Science and Technology
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• v.45 no.5
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• pp.580-587
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• 2017

Woodfiber insulation board can be considered as a one of the key material for low energy consumption, comfortable and safety construction of residential space because of its eco-friendly and high thermal insulation performance. This study was carried out to investigate the formaldehyde (HCHO) total volatile organic compounds (TVOC) emission properties and combustion shapes by flame test of low density fiberboards (LDFs) prepared with different adhesives. HCHO TVOC emission and combustion properties of LDFs prepared by melamine urea formaldehyde (MUF), phenol formaldehyde (PF), emulsified methylene diphenyl diisocyanate (eMDI) and latex resin adhesives were measured by desiccator method, 20 L chamber method, and flame test, respectively. As results, LDFs manufactured by MUF, eMDI and latex resin adhesives satisfied the Super $E_0$ grade of HCHO emission performance except PF resin. Furthermore, TVOC emission of all LDFs were satisfied the Korean indoor air quality standard (below $400{\mu}g/m^2{\cdot}h$). Especially, LDF with eMDI resin adhesive showed the lowest HCHO and TVOC emissivity, that $0.14mg/{\ell}$, $12{\mu}g/m^2{\cdot}h$, respectively. However, eMDI emitted the small amount ($3{\mu}g/m^2{\cdot}h$) of toluene in VOC components. In the flame test, LDF with MUF resin adhesives showed the most favorable shape after flame test compare to LDFs prepared other adhesives. Based on HCHO and TVOC emission, and combustion shapes, MUF resin adhesive may be recommended to prepare LDF for insulation purpose.