• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.5
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• pp.601-604
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• 2009

This study was conducted to examine the effect of aqueous chlorine dioxide treatment as a washing method on removal of pesticide residues. Three pesticides of chlorpyrifos, diazinon, and metalaxyl, which are commonly used in vegetable crops, were treated with 10, 50, and 100 ppm of aqueous chlorine dioxide and decomposition of the pesticides was determined using gas chromatography. Three pesticides used in this study were decomposed by aqueous chlorine dioxide treatment and removal rate was proportional to treatment time as well as concentration of aqueous chlorine dioxide. In particular, 100 ppm of aqueous chlorine dioxide treatment decreased the pesticides efficiently. In addition, lettuce was treated by dipping in distilled water and 100 ppm aqueous chlorine dioxide, respectively, and was compared regarding removal efficiency of the pesticides. The results revealed that washing with 100 ppm aqueous chlorine dioxide for 10 min was the most effective for removing the pesticides. These results suggest that aqueous chlorine dioxide can be used as a washing method of fresh produce to remove the residual of pesticides.

• Research in Plant Disease
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• v.11 no.1
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• pp.39-42
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• 2005

Powdery mildew, caused by Sphaerotheca aphanis var. aphanis, is an economically significant disease of strawberry in Korea. When powdery mildew is not controlled adequately, it often spreads rapidly through strawberry plants and damage is associated with reduced yields. Proper timing of fungicide applications is, therefore, essential for effective disease control. This study evaluated the efficacy by application schedule of fungicides before harvest stage for preventing powdery mildew in 2001-2003. The systemic fungicides, azoxystrobin, kresoxim-methyl, and cupper fungicide DBEDC were applied preventively during the first part of the cultivating season. Preventative applications of DBEDC by dipping treatment before transplanting and kresoxim-methyl by foliar spray before blooming stage were one of the most effective control schedule tested to prevent and manage this disease. This research demonstrated the significance of application time to control of powdery mildew, particularly provided elimination unnecessary sprays of agrochemicals and reduction costs for strawberry growers.

• Journal of the Korean Society of Food Culture
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• v.10 no.4
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• pp.291-300
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• 1995

The purpose of this paper is to survey various recipes of the roasted beef with twenty three classical cookboods written before 1943. The roasted beefis found total 32 times in the literature which can be classified into seven groups such as the roasted rib, roasted foot, roasted tail, roasted heart, roasted gall, roasted kidney and roasted fresh meat. The most frequent one is the roasted rib appearing eight times and the next is the roasted sliced beef with seasoning appearing seven. This proves that the those recipes have been the most favorite ones to Korean people for a long time. The roasted rib has been found since the middle of the 17th century, but the process of roasting ribs again with seasoning after three successions of dipping shortly into cold water in the midst of roast wasz disappeared. The roasted sliced beef with seasoning originated since the late 18th century, and the roasted beef with salt since the early 19th century which has been inherited as the roasted raw upper part of roasted beef recipes have been continued until today in the similar manner. Generally the roasted meat with bones and the roasted internal organs started in 1766 earlier than the roasted fresh meat by a century. The main ingredients were rib, foot, tail, heart, gall, kidney, fresh meat and knee bone, and the seasonings were mixtures of scallion stalk, garlic, pepper, oil, soy sauce and sesame seed powder. And peculiarly salted shrimp, pear juice, ginger were added to seasonings and pine nut powder was used as decorating ingredient.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.1
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• pp.104-115
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• 1992

The rice culture techniques included 'Jodosukyungbeob'(旱稻水耕法 : culture techniques of early-ripening paddy rice), 'Mandosukyungbeob' (晩稻水耕法) : culture techniques of late-Ripening paddy rice 'Handobeob'(旱稻＆lt;山稻＆gt;法 : culture techniques of upland rice), 'Myojongbeob'(苗種法 : culture techniques of paddy rice by transplanting), 'Kunangbeob'(乾秧法 : culture techniques of rice by transplanting which rears seeding in dry paddy) and 'Sudogunpanongbeob'(水稻乾播農法 : culture techniques of paddy rice seeding in dry field). Especially, 'Kunangbeob' and 'Sudogunpanongbeob' were originally developed in Korea as seen in 1600s(Kyoungje : 經濟) and early 1800s (Yoji : 要旨). In 'Jodosukyungbeob' it took 9 days for seed dipping, water-sprouting and prevent damage by birds, each for 3 days in China, but in Korea seed dipping in water took 3 days and the rest of the procedures were flexibly established. In matured soils, practices were fall plowing right after harvest, recognition of effective tillering and additional fertilization use of human manure, and stimulation of sprouting by lime application. The unique culture techniques adequate for Korean situations were practiced, which included weed control after draining accurately for 3 to 4 times, draining at mid season for improving wind and drought tolerance, rice harvesting at appropriate time for preventing grain shattering, and seeding in rows. 'Mandosukyungbeob' was improved techniques contrast to those of China, and the major contents were selection of proper varieties, good stand establishment by seeding high rates, induction of vigorous tillers, and adoption of 'Jokjongbeob'(足種法 : seeding method by foot). Also, one of the most prominent rice cultures by our ancestors was 'Kunpanongbeob' that was systemized form habitual practice of Pyongan Province. The unique technique actualized was 'Hando [旱稻(山稻)]' culture technique which was the combinations of 'Jokjongbeob', root stimulation method, and disaster-tolerant mixture cropping with adoptation of variety theory, although it was originated from China. The transplanting techniques has come before 'Jikseol'($\ulcorner$直說$\lrcorner$) and its merits were sufficiently realized. However, this method was basically prohibited from the early Chosun dynasty because extremely bad harvest was expected under drought conditions and insufficient conditions of water storage. But, it was permitted in the areas that contained water all the times and in case of large-scale farming especially. Most of rice culture was transplanted in the end of the Chosun dynasty because transplanting was continuously spreaded in the three southern provinces of Korea. Under these circumstances, transplanting technique was improved from the early to the end of the Chosun dynasty by weed control, fertilizing, water management, and quadratic transplanting. Based on these techniques, agricultural productivity was improved 5 times by that time. 'Kunpanongbeob' was created and developed properly for Korean conditions that is dry in early season and flooding in late season. This was successively developed and established into transplanting technique of nursery seedling.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.28 no.5
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• pp.265-276
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• 2016

The 2011 Tohoku, Japan Tsunami, which occurred on March 11, 2011, reached the Korean Peninsula and was recorded at numerous tide stations. In the records of the north-eastern tide stations, tsunami forerunners were found in only about a few minutes after the earthquake, which was much earlier than the expected arrival time based on a numerical simulation. Murotani et al. (2015) found out that the bathymetry effect is related to the tsunami forerunners observed in Japan and Russia. In this study, the tsunami forerunners observed in Korea were well reproduced by a numerical simulation considering the bathymetry effect. This indicates that it is important to consider the bathymetry effect for a tsunami caused by an earthquake on shallowly dipping fault plane(e.g. 2011 Tohoku, Japan Earthquake). However, since the bathymetry effect requires additional computation time, it is necessary to examine the problems that results from applying the bathymetry effect to the tsunami warning system.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.6
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• pp.375-380
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• 2017

This study assessed the technology to minimize the discoloration to reduce the defect rate and penetrate the curing solution through the egg shells to produce quality smoked eggs that meet the preference of consumers. The discoloration refers to the defects on the colors of egg shells due to overheated smoking fluids, causing the eggs to be discarded. The manufacturing process was prepared by the manufacturer of the regular smoked egg manufacturing process. A preliminary study found that the preferred salinity of smoked eggs was 1.67~2.00% and the major processing factors have been set to maintain the optimal salinity of smoked eggs and an industrially attainable minimum defect rate below 3%. When the eggs were aged at $50^{\circ}C$ for 96 hours to produce the smoked eggs, the discoloration rate was 0%. When the circulatory dipping method was applied, 3.00% salinity was achieved after 8 hours. When the eggs were smoked at that time, the salinity was 1.67%. With a $2.07kg/cm^2$ pressure, 3.33% salinity was achieved after 4 hours and 2.00% salinity was achieved when the smoked eggs were produced. To identify the most efficient pressurizing method, 0.52, 1.55, 1.86, 2.07, 2.38, 2.58, and $3.62kg/cm^2$ were applied, the discoloration rate was 2.2% after 4 hours under a $2.07kg/cm^2$ pressure. The aging and pressurized method is considered to be the basis for reducing the manufacturing time and decreasing the rate of error during the smoked eggs process.

• Korean Journal of Agricultural Science
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• v.40 no.4
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• pp.325-331
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• 2013

This experiment has been carried out to determine optimal culture conditions for the production of cut flowers and tubers of Calla (Zantedeschia 'Golden Affair' and 'Black Magic') in highlands. Treatments consisted of various levels of root zone environments, Results are as follows: Calla 'Golden Affair' were grown with different mulching materials such as Non-mulching, Black film, reflective film, Rice hull. Mulching materials resulted in no difference in the number of cut flowers but flower length was highest in reflective film. Calla 'Black Magic' were treated with various soil water content, soil type and watering time. Number of cut flowers and flower quality were greatest when the plants were watered at -80 kPa soil water content. No symptoms of soft rot (Erwinia carotovora) was observed at this soil water content. The occurrence of soft rot was observed with similar percentage according to soil type and the soil water content. When Calla 'Black Magic' were watered at the time of soil surface drying, growth was greater compared to others. Air temperature and PPF affected plant growth and photosynthesis. Photosynthetic rate was greatest at $25^{\circ}C$ and PPF $200{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, while lowest at $28^{\circ}C$ and PPF $800{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. Soft rot did not occur without regard to dipping treatment (0, 5, 10, 24, 48 hours) when the day and night temperature were maintained at $25^{\circ}C$ and $20^{\circ}C$, respectively.

• Economic and Environmental Geology
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• v.32 no.5
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• pp.445-454
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• 1999

The Sanjeon Au-Ag deposit consists of three subparallel hydrothermal quartz-calcite veins which filled fault-related fractures (generally $N20^{\circ}$ to 35"W-trending and $70^{\circ}$ to $80^{\circ}$ SW-dipping) within quartz porphyry. The vein mineralization shows an apparent variation of mineral assemblages with paragenetic time: (1) early, white quartz + pyrite + arsenopyrite + brown sphalerite, (2) middle, white (vein) to clear quartz (vug) + base-metal sulfides + electrum + argentite, (3) late, calcite + pyrite + native silver. Mineralogic and fluid inclusion data indicate that gold-silver minerals were deposited at temperatures from 2l $0^{\circ}$ to $250^{\circ}$ with salinities of 4 to 5 wt. % equiv. NaCl and log fS2 values from -14.0 to -12.2 atm. The linear relationship between homogenization temperature and salinity data indicates that gold-silver deposition was a result of meteoric water mixing. Ore mineralization occurred at pressure conditions of about 70 bars, which corresponds to the mineralization depths of about 260 m to 700 m. There is a remarkable decrease of the calculated 1)180 values of water from 1.3 to -9.7%0 in hydrothermal fluid with increasing paragenetic time. This indicates a progressive increase of meteoric water influx in the hydrothermal system at the Sanjeon deposit. Oxygen-hydrogen, sulfur, and carbon isotope values of hydrothermal fluids indicate that the ore mineralization was formed largely from meteoric waters with the contribution of sulfur and carbon from a deep igneous source.

• Geophysics and Geophysical Exploration
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• v.16 no.2
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• pp.71-78
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• 2013

The one-way wave equation migration is much more computationally efficient comparing with reverse time migration and it can provide better image than the migration algorithm based on the ray theory. We have developed the prestack depth migration module adopting (GS) propagator designed for vertical transverse isotropic media. Since GS propagator considers the higher-order term by expanding the Taylor series of the vertical slowness in the thin slab of the phase-screen propagator, the GS migration can offer more correct image for the complex subsurface with large lateral velocity variation or steep dip. To verify the validity of the developed GS migration module, we analyzed the accuracy with the order of the GS propagator for VTI media (GSVTI propagator) and confirmed that the accuracy of the wavefield propagation with the wide angles increases as the order of the GS propagator increases. Using the synthetic seismic data, we compared the migration results obtained from the isotropic GS migration module with the anisotropic GS migration module. The results show that the anisotropic GS migration provides better images and the improvement is more evident on steeply dipping structures and in a strongly anisotropic medium.

• Journal of Aquaculture
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• v.10 no.4
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• pp.417-424
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• 1997

This study was carried out to investigate the effects of experimental formulated diets, commercial diets and natural diet(dried Undaria) on growth and body composition of Haliotis discus hannai. Experimental diets was formulated to provide 34.1% protein and 7.5% lipid, and prepared by different $CaCl_2$ concentration (5, 10 and 15%) and dipping time (10, 20 and 60 second) in solution. The juvenile abalone average weighing 0.3g were distributed in a flow-through aquarium system using a cmpletely randomized desing with 13 diets and 3 replictes per diet (50 abalone/tank), and fed diets for 17 weeks. The abalone fed the time nine experimental formulated diets and two commercial diets showed better growth performance than that of natural diets. No significant differences were found among abalone fed the experimental diets and commercial diets in survival rate, weight gain, soft body weight and soft body composition (P>0.05).