• Journal of the Korean Society of Marine Environment & Safety
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• v.21 no.6
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• pp.617-636
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• 2015

The Mokpo coastal waters receive discharges from three artificial lakes(Youngsan, Youngam, Geumho) and other terrigenous freshwater inflows(streams, sewage treatment effluent, fresh groundwater), which exhibit very high concentrations of nutrients and/or organic matters. To understand spatial distributions of nutrients(DIN, DIP, DSi) and other water quality parameters(Chl-a, water temperature, salinity, DO, COD, SS), field surveys were conducted at 10 stations in the Mokpo harbor and adjacent estuaries on May, July, September, and November 2008 within 10 days following discharge events from artificial lakes. In this study, the freshwater flow rate influxed by the operation of sea dike sluice had significant influence on water qualities of the Mokpo coastal waters, although nutrient concentrations in other freshwater sources such as streams, sewage treatment effluent, and fresh groundwater were much higher. As a result of statistical analysis, DIN, COD, and Chl-a had a negative correlation with salinity. Therefore it was shown that discharge extents, time, and nutrients from the Youngsan lake were major impact factors dominating the spatial characteristics of nutrients and other water quality parameters in the Mokpo harbor and adjacent waters. However, despite non-discharge from the Youngsan Lake on September of this investigated period, it was observed that the nutrient addition was taking place in the lower layer of the estuary suggesting nutrient supply through different pathways. This result has emphasized the need to implement the combined assessment about the cumulative impacts on the Youngsan Estuary environment and ecosystem due to freshwater inputs derived from the artificial lakes as well as other terrigenous inflows, or benthic releases.

• Korean Journal of Optics and Photonics
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• v.27 no.1
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• pp.18-24
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• 2016

To effectively utilize a flash and predict its effects on an infrared device, it is essential to know the infrared characteristics of the flash source. In this paper, a study of the IR characteristics of flash light sources is carried out. The IR characteristics of three flash sources, of which two are combustive and the other is explosive, are measured with an IR characteristic measurement system over the middle- and long-wavelength infrared ranges. From the measurements, the radiances over the two IR ranges and the radiative temperatures of the flashes are extracted. The IR radiance of flash A is found to be the strongest among the three, followed by those of sources C and B. It is also shown that the IR radiance of flash A is about 10 times stronger than that of flash B, even though these two sources are the same type of flash with the same powder. This means that the IR radiance intensity of a combustive flash source depends only on the amount of powder, not on the characteristics of the powder. From the measured radiance over MWIR and LWIR ranges for each flashes, the radiative temperatures of the flashes are extracted by fitting the measured data to blackbody radiance. The best-fit radiative temperatures (equivalent to black-body temperatures) of the three flash sources A, B, and C are 3300, 1120, and 1640 K respectively. From the radiance measurements and radiative temperatures of the three flash sources, it is shown that a combustive source radiates more IR energy than an explosive one; this mean, in turn, that the effects of a combustive flash on an IR device are more profound than those of an explosive flash source. The measured IR radiances and radiative temperatures of the flash sources in this study can be used to estimate the effects of flashes on various IR devices, and play a critical role for the modeling and simulation of the effects of a flash source on various IR devices.

• Korean Journal of Food Science and Technology
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• v.28 no.2
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• pp.345-351
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• 1996

Studies on extraction and color characteristics of purple sweet potato (PSP) pigment were performed to provide the basic information for the utilization of PSP as a new source of natural food colorant. PSP pigment was extracted well with the polar solvents such as distilled water, ethanol, and methanol. but hardly extracted with the non-polar solvents. Among the tested solvents, 20% ethanol solution containing 0.1% citric acid was found to be the most efficient for extraction of the pigment from PSP. PSP contained high amount of pigment not only in the epidermis but also in the flesh of the potato. The PSP pigment was heat stable even under pretreatments such as autoclaving and blanching of the potato before extraction. The optimum temperature of the extraction for the PSP Pigment was decided to be $30^{\circ}C$ by considering the stability and the rate of extraction. The pigment was markedly influenced by the change of pH. The color of the pigment solution was red at the pH range of $1.0{\sim}3.0$, became blue at $7.0{\sim}8.0$, then turned green at $9.0{\sim}10.0$. A characteristic batho-chromic shift of the pigment solution was observed as the pH of the solution increased.

• Journal of Bio-Environment Control
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• v.17 no.4
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• pp.336-341
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• 2008

The objective of this research was to investigate the suitable cultivar for organic strawberry (Fragaria ananassa Duch.) cultivation in Korea. The six strawberry cultivars which were bred and commonly cultivated in Korea as forcing and semi-forcing culture were tested in this experiment. To achieve the objectives, various characteristics of these cultivars were investigated for two consecutive years such as growth habit, yield, fruit quality and occurrence rate of disease/pest. As results of this research, the total yield of 'Seolhyang' was the highest among cultivars tested in both forcing and semi-forcing cultivation. The average of soluble solid contents (SSC) in 'Seolhyang' was $12.0^{\circ}Bx$ that is lower than other cultivars and especially below $10^{\circ}Bx$ after March (high temperature period). But there was not much difference in SSC among 6 cultivars until the end of February. The average of hardness in 'Seolhyang' was 279g/${\phi}5\;mm$ which was a little higher than that of 'Akihime'. Titration acidity (TA) in 'Maehyang' was 0.69% which was the highest value among 6 cultivars. Total fresh/root weight of 'Seonhong' and leaf area of 'Seolhyang' were significant among other cultivars' ones in forcing culture. Growth habits (fresh weight, root weight, leaf area, etc.) showed no significant difference among cultivars in semi-forcing culture. The lowest occurrence rate for powdery mildew and aphids was found in 'Seolhyang', but gray mold was severer than other cultivars. The density of two spider mites was the lowest in 'Redpearl'. We have concluded that 'Seolhyang' is the most suitable cultivar for organic strawberry cultivation by the result of yield, fruit quality and resistance of disease/pest.

• Economic and Environmental Geology
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• v.35 no.3
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• pp.203-210
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• 2002

In order to elucidate the growth mechanism of sulfide chimney formed as a result of seafloor hydrothermal mineralization, we carried out the mineralogical and fluid inclusion studies on the inactive, sulfide- and silica-rich chimney which has been recovered from a hydrothermal field in the Cleft segment of the Juan de Fuca Ridge. According to previous studies, many active and inactive vents are present in the Cleft segment. The sulfide- and silica-rich chimney is composed of amorphous silica, pyrite, sphalerite and wurtzite with minor amounts of chalcopyrite and marcasite. The interior part of the chimney is highly porous and represents a flow channel. Open spaces within chimneys are typically coated with colloform layers of amorphous silica. The FeS content of Zn-sulfides varies widely from 13.9 to 34.3 mole% with Fe-rich core and Fe-poor rims. This variation possibly reflects the change of physicochemical characteristics of hydrothermal fluids. Chemical and mineralogical compositions of the each growth zone are also varied, possibly due to a thermal gradient. Based on the microthermometric measurements of liquid-rich, two-phase inclusions in amorphous silica that was precipitated in the late stage of mineralization, minimum trapping temperatures are estimated to be about 1140 to 145$^{\circ}$C with the salinities between 3.2 and 4.8 wt.% NaCI equiv. Although the actual fluid temperatures of the vent are not available, this study suggests that the lowtemperature conditions were predominant during the mineralization in the hydrothermal field at Cleft segment. Comparing with the previously reported chimney types, the morphology, colloform texture, bulk chemistry, and a characteristic mineral assemblage (pyrite + marcasite + wurtzite + amorphous silica) of this chimney indicate that the chimney have been formed from a relatively low-temperature (<250$^{\circ}$C) hydrothermal fluid that was changed by sluggish fluid flow and conductive cooling.

• Journal of Animal Science and Technology
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• v.50 no.3
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• pp.391-400
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• 2008

Odor management is significantly concerned with sustainable livestock production because odor nuisance is a primary cause for complaint to neighbors. This study was conducted to measure the concentration of odorous compounds, odor intensity, and odor offensiveness at unit process in animal waste treatment facility combined composting and methane fermentation process by an instrumental analysis and direct olfactory method. Ammonia, sulfur-containing compounds, and volatile fatty acid were analyzed at each process units and boundary area in summer and winter, respectively. Higher concentration of odorants occurred in the summer than in the winter due to high ambient temperature. The maximum concentration of odorants was detected in composting pile when mixed manure was being turned followed by inlet, curing, outlet, and screen & packing process. Highest concentration of detected odorous compounds was ammonia ranging from 3.4 to 224.7 ppm. Among the sulfur-containing compounds measured, hydrogen sulfide was a maximum level of 2.3 ppm and most of them exceeded reported odor detection thresholds. Acetic acid was the largest proportion of VFA generated, reaching a maximum of 51 to 89%, followed by propionic and butyric acid at 1.9 to 35% and 1.8 to 15%, respectively. Malodor assessment by a human panel appeared a similar tendency in instrumental analysis data. Odor quotient for predicting major odor-causing compounds was calculated by dividing concentrations measured in process units by odor detection thresholds. In the composting process, hydrogen sulfide, ammonia, dimethyl sulfide, and methyl mercaptan were deeply associated with odor-causing compounds, while the major malodor compounds in the inlet process were methyl mercaptan, hydrogen sulfide, and butyric acid.

• Journal of Sericultural and Entomological Science
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• v.45 no.1
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• pp.10-17
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• 2003

This study was carried out to analyze physicochemical characteristics of sericin cocoon from silkworm, Bombyx mori. The degumming loss increased with increasing treatment time up to 2 hr, and temperature up to 130$^{\circ}C$. At 130$^{\circ}C$, degumming loss of Nd-s jam and Nd$\^$H/ jam were 100% while that of Baegok jam was 24%. Nd-s jam and Baegok jam ha high glycine content of 29.1∼46.3 mol% where as Nd$\^$H/ jam had high serine content of 32.6 mol%. Thermal denaturation temperatures were found at 218$^{\circ}C$ for Nd-s jam, 216$^{\circ}C$ for Nd$\^$H/ jam, and 218$^{\circ}C$ for Baegok jam. Before degumming, crystallinities obtained by FT-IR analysis were 44.3, 43.7, and 59.9% for Nd-s jam, Nd$\^$H/ jam, and Baegok jam respectively. After degumming, crystallinity increased to 61.8% for Baegok jam. Before degumming, crystallinitics obtained from XRD were 35.9, 33.5, and 47.2%, for Nd-s jam, Nd$\^$H/ jam, and Baegok jam. After degumming, crystallinity increased to 49.8% for Baegok jam. The molecular weight of Nd$\^$H/ jam were 9,417 in 1 hr, 3,744 in 2 hr, 4,944 in hr, and 3,910 in 6 hr.

• Pediatric Infection and Vaccine
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• v.16 no.1
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• pp.40-46
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• 2009

Purpose : The purpose of this study was to identify useful predictors for diagnosing bacterial meningitis and performing CSF studies in febrile infants three months or younger. Methods : Six hundred and fifty two febrile infants with a rectal temperature ${\geq}38.0^{\circ}C$ presented from January 2003 to April 2008 and were retrospectively studied. The total white blood cell count (WBC), band count, absolute neutrophil count (ANC), quantitative C-reactive protein (CRP) and blood cultures were performed on admission. The clinical variables associated with bacterial meningitis were analyzed. Results : In patients with bacterial meningitis, the clinical variables including CRP (P=0.036), band count (P=0.037), ANC (P=0.036) and age (P=0.001) were significantly different. The area under the receiver-operating characteristic curve was 0.969 for CRP, 0.946 for the band count, 0.765 for the ANC and 0.235 for age. A CRP cutoff point of 8 mg/dL was determined to maximize both the sensitivity and specificity (sensitivity 83%, specificity 95%, likelihood ratio 16.6). A CRP concentration of <7 mg/dL "ruled-out" bacterial meningitis, with a likelihood ratio of 0.17, a posttest probability of <0.1% and negative predictive value 91%. A CRP concentration greater than 9 mg/dL had a much higher likelihood ratio (20.1) than the band count (16.6) and ANC (2.2). Conclusion : The CRP concentration was a useful laboratory test for the differential diagnosis of bacterial meningitis among febrile infants three months of age or younger. A CRP concentration of <7 mg/dL effectively ruled out bacterial meningitis; a value ${\geq}9mg/dL$ increased the clinical suspicion of bacterial meningitis and the need for CSF evaluation.

• Korean journal of food and cookery science
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• v.30 no.6
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• pp.670-678
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• 2014

The purpose of this study was to find the optimal swelling method and condition for seacucumber to improve its taste and texture to accomodate the rapid increase of consumption. Another purpose was to try to determine an easy way to soak dried sea-cucumber under different conditions, and identify the influence of swelling time on the texture of sea-cucumber, in order to reduce preparation time and provide basic data for easy handling. After boiling or steaming for six different periods including 5, 15, 30 and 60 minutes the texture of the sea-cucumbers were compared, For the additive test, the sea-cucumbers were boiling for 30 minutes period with 4 different additives and the textures were compared, Since the texture is an important characteristic of sea-cucumber, there are many variables that affect this property including the, drying and preservation methods. This study provides basic understanding of the influence of the heating method, time and temperature on the swelling of sea-cucumber for handy use at processing sites.

• Korean Journal of Breeding Science
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• v.41 no.3
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• pp.349-353
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• 2009

We developed a new barley cultivar "Dami" (Hordeum vulgare L.) with the auricleless gene lig (al, li, aur-a). The characteristic of auricleless is a spontaneous mutant type which has known as a monogenic recessive gene. The plant with the gene has erect leaf blades because of no auricle. The cultivar was derived from a cross between 'BGS60' and 'Kangbori'. 'BGS60' has the auricleless gene (li), while 'Kangbori' showed a high biomass with winter hardiness and resistance to BaYMV (Barley Yellow Mosaic Virus). Subsequent generations were handled by the bulk method in a pedigree selection program. A promising line showed both high yield and lodging resistance in the yield trials at Iksan in 2003 to 2004, and designated as Iksan414. The line was subsequently evaluated for winter hardiness, earliness, and yield in the seven locations around Korea for three years from 2005 to 2007 and was designated as "Dami" and released. It has the growth habit of III, erect plant type, green leaf and stem similar to the check cultivar 'Sunwoo' Its heading date was April 30, and maturing date May 31 in paddy field conditions, which were similar to those of 'Sunwoo' respectively. The cultivar Dami was 97 cm in culm length, had 643 spikes per $m^2$ and higher leaf dry weight, and better adaptability to dense planting, winter hardiness, and resistance to BaYMV than the check cultivar did. The average forage yield of "Dami" was about 12 ton $ha^{-1}$ in dry matter (33 ton $ha^{-1}$ in fresh matter) in paddy field. "Dami" also showed 7.5% of crude protein content, 28.5% of ADF (Acid Detergent Fiber), 50.1% of NDF (Neutral Detergent Fiber), and 66.4% of TDN (Total Digestible Nutrients), including higher grade of silage quality for whole crop barley. This cultivar would be suitable for the area where the daily minimum temperature of January is above $-8^{\circ}C$ in Korean peninsula.