• Biomedical Science Letters
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• v.4 no.1
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• pp.65-72
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• 1998

Recently there have been frequent reports on human infection caused by the Diphyllobothridae in Korea. The adequate opportunities for Koreans to eat raw fish, the primary infection medium of cestodes and the human infection through drinking water by cyclops, the first intermediate host are believed to be main reasons for the infection. The first task of this study was to classify and diagnose the species by differentiating morphological characteristic between scolex and proglottids of cestodes. However, the initially available diagnosis was done with the patient's symptoms and the eggs obtained from his stool. It is important to differentiate the species by the eggs of Diphyllobothrium latum especially in that it can help get advance information for a more reliable analysis in the near future. The morphological and diagnostic results from proglottids and eggs of Diphyllobothrium latum, Diphyllobothrium latum parvum and Spirometra erinacei are as follows； In each kind of cestodes from the patient's stool, the shape and size of 50 eggs were measured. Eggs of Diphyllobothrium latum had an operculum and were ovoidal or ellipsoid to elliptical in shape. Eggs of Diphyllobothrium latum parvum were more ovoidal in shape and smaller in size than Diphyllobothrium latum. And eggs of Spirometra erinacei were asymmetrical in width and long and slender in shape. The average lengths and widths of Diphyllobothrium latum, Diphyllobothrium latum parvum and Spirometra erinacei were 61.4$\times$41.7 $\mu\textrm{m}$, 55.9$\times$41.4 $\mu\textrm{m}$ and 66.7$\times$36.4 $\mu\textrm{m}$, respectively. After the segments of each cestode were fixed, embedding and hematoxylin-eosin dyeing on a microtome-made specimen were done. The micrographs of the semicon's aceto-carmine dyed specimen showed that Diphyllobothrium latum and Diphyllobothrium latum parvum had a centrally-located genital gland and an opened uterine pore. The yolks were observed on both sides of proglottids and had a typical rosette pattern. Yet, Diphyllobothrium latum parvum was shown smaller than Diphyllobothrium latum in the micrograph. Proglottids of Spirometra erinacei displayed that the uterus was rolled spirally more than five to seven times, and connected successively to the seminal vesicle in the cirrus sac. Shown above, this study was performed to measure the size of eggs and analyze the morphological characteristics of proglottids and provided the measurements of three types of cestodes obtained by a light microscope.

• Journal of the Korea Concrete Institute
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• v.17 no.1 s.85
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• pp.129-137
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• 2005

In Korea, due to the insufficiency of natural aggregates and increasing needs of crushed stones, it is necessary to examine the alkali-silica reaction of the crushed stones. The reaction produces an alkali-silica reaction gel which can imbibe pore solution and swell to generate cracks that are visible In affected concrete. In general, crushed stones are tested by petrograptuc examination, chemical method and mortar-bar method, but the most reliable method Is mortar-bar test. This study tested alkali-silica reactivity of crushed stones of various rock types using ASTM C 227 and C 1260, and compared the results of two test methods. This study also analyzed effects of particle size and grading of reactive aggregate on alkali-silica reaction expansion of mortar-bar. The effectiveness of mineral admixtures to reduce detrimental expansion caused by alkali-silica reaction was investigated through the ASTM C 1260 method. The mineral admixtures used were nv ash, silica fume, metakaolin and ground granulated blast furnace slag. The replacement ratios of 0, 5, 10, 15, 25 and $35\%$ were commonly applied for all the mineral admixtures and the replacement ratios of 45 and $55\%$ were additional applied for the admixtures that could maintain workability. The results indicate that replacement ratios of $25\%$ for ay ash, $10\%$ for silica fume, $25\%$ for metakaolin or $35\%$ for ground granulated blast furnace slag were most effective to reduce alkali-silica reaction expansion under the experimental conditions.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.7
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• pp.694-699
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• 2008

Considering the severe regulation associated with sludge treatment such as direct landfill and ocean dumping, there is no doubt in that an advanced study for the proper treatment of sludge is urgently needed in near feature. As one of viable method for sludge treatment, fry-drying of sludge by waste oil has been investigated in this study. The fundamental mechanism of this drying method lies in the phenomenon of rapid moisture escape in the sludge pore toward oil media. This is caused by the severe pressure gradient formed by the rapid oil heating between sludge and oil. As part of research effort of fry-drying using waste oil, a series of basic study has been made experimentally to obtain typical drying curves as function of important parameters such as drying temperature, drying time, oil type and geometrical shape of sludge formed. Based on this study, a number of useful conclusion can be drawn as following. The fry-drying method by oil immersion was found quite effective in the removal efficiency of sludge moisture, in general, the moisture content decreases significantly after 10 minutes and the whole moisture content was less than 5% after 14 minutes regardless of the drying temperature. The increase of oil temperature up to 140$^{\circ}C$ favors significantly for the removal of moisture but there was no visible difference above 140$^{\circ}C$. As expected, the decrease of diameter in sludge was efficient in drying due to the increased surface area per unit volume. Further, the effect of oil property by the change of oil type was noted. To be specific, for the case of engine oil the efficiency was found to be remarkably delayed in moisture evaporation compared with that of vegetable oil due to the increased viscosity of engine oil. It produced a result of increasing the evaporation of moisture largely relatively high in the drying temperature over 140$^{\circ}C$ compared with the drying temperature 120$^{\circ}C$ drying temperature as the drying time passed. Accordingly, the drying temperature is considered desirable as keeping over 140$^{\circ}C$ regardless of a sort of used oil.

• Journal of the Korean Wood Science and Technology
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• v.46 no.1
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• pp.17-28
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• 2018

In this study, catalytic activation using sulfuric acid lignin (SAL), the condensed solid by-product from saccharification process, with potassium hydroxide at $750^{\circ}C$ for 1 h in order to investigate its potential to nanoporous carbon In this study, catalytic activation using sulfuric acid lignin (SAL), the condensed solid by-product from saccharification process, with potassium hydroxide at $750^{\circ}C$ for 1 h in order to investigate its potential to nanoporous carbon material. Comparison study was also conducted by production of activated carbon from coconut shell (CCNS), Pinus, and Avicel, and each activated carbon was characterized by chemical composition, Raman spectroscopy, SEM analysis, and BET analysis. The amount of solid residue after thermogravimetric analysis of biomass samples at the final temperature of $750^{\circ}C$ was SAL > CCNS > Pinus > Avicel, which was the same as the order of activated carbon yields after catalytic activation. Specifically, SAL-derived activated carbon showed the highest value of carbon content (91.0%) and $I_d/I_g$ peak ratio (4.2), indicating that amorphous large aromatic structure layer was formed with high carbon fixation. In addition, the largest changes was observed in SAL with the maximum BET specific surface area and pore volume of $2341m^2/g$ and $1.270cm^3/g$, respectively. Furthermore, the adsorption test for three kinds of organic pollutants (phenol, 2,4-Dichlorophenoxyacetic acid, and carbofuran) were conducted, and an excellent adsorption capacity more than 90 mg/g for all activated carbon was determined using 100 ppm of the standard solution. Therefore, SAL, a condensed structure, can be used not only as a nanoporous carbon material with high specific surface area but also as a biosorbent applied to a carbon filter for remediation of organic pollutants in future.

• Journal of Animal Environmental Science
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• v.8 no.1
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• pp.9-16
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• 2002

This study was conducted to develope the new solid separating system which can be efficiently and economically removed the solid parts in high pollutants concentration of pig slurry. The pollutants concentration, BOD$_{5}$ , COD and SS of the slurry used in this study was 15,990($\pm$2,389)mg/l, 20,004($\pm$5,512)mg/l and 26,486($\pm$5,935)mg/l, respectively. After removal of solid part in slurry, the pollutants concentration, BOD$_{5}$, COD and SS was change into 5,617($\pm$690)mg/l, 5,553($\pm$633)mg/land 1,456($\pm$341)mg/l, respectively in the Fixed biological membrane tank. The reduction of the pollutants concentration of suspend liquid through membrane will be allowed to greatly improve the water purification by an Activated sludge method. This separating system consisted of a temporary storage, a circulating tank and a Fixed Biological membrane tank. A temporary storage which has a draining system of screw type and an aeration device played a tremendous role in draining the solid by filled an aeration of 0.3 l/min. A Fixed Biological membrane tank of which a styrofoam filled in a 2/3 volume as a Biological media was fixed by a stainless steel net (pore size : 0.5mm) to separate the liquid layer of influx in them. The separating system efficiency factors were the speed of screw motor, cycle number of slurries in a circulating tank and moisture contents of solid effluent through the screw path. Although the pollutants concentration was very variable in temporary storage, the final concentration of $BOD_5$ and SS, except COD of the suspended liquid in a Fixed biological membrane were not different regardless of cycle number of a circulating tank. Moisture contents of effluent from temporary storage was 73% under the speed 1 ppm of screw motor and 62% under the 1/4rpm of it.

• Tunnel and Underground Space
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• v.30 no.4
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• pp.320-334
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• 2020

This study presents an application of hydro-mechanical coupled Particle Flow Code 3D (PFC3D) to simulation of fluid injection induced fault slip experiment conducted in Mont Terri Switzerland as a part of a task in an international research project DECOVALEX-2019. We also aimed as identifying the current limitations of the modelling method and issues for further development. A fluid flow algorithm was developed and implemented in a 3D pore-pipe network model in a 3D bonded particle assembly using PFC3D v5, and was applied to Mont Terri Step 2 minor fault activation experiment. The simulated results showed that the injected fluid migrates through the permeable fault zone and induces fault deformation, demonstrating a full hydro-mechanical coupled behavior. The simulated results were, however, partially matching with the field measurement. The simulated pressure build-up at the monitoring location showed linear and progressive increase, whereas the field measurement showed an abrupt increase associated with the fault slip We conclude that such difference between the modelling and the field test is due to the structure of the fault in the model which was represented as a combination of damage zone and core fractures. The modelled fault is likely larger in size than the real fault in Mont Terri site. Therefore, the modelled fault allows several path ways of fluid flow from the injection location to the pressure monitoring location, leading to smooth pressure build-up at the monitoring location while the injection pressure increases, and an early start of pressure decay even before the injection pressure reaches the maximum. We also conclude that the clay filling in the real fault could have acted as a fluid barrier which may have resulted in formation of fluid over-pressurization locally in the fault. Unlike the pressure result, the simulated fault deformations were matching with the field measurements. A better way of modelling a heterogeneous clay-filled fault structure with a narrow zone should be studied further to improve the applicability of the modelling method to fluid injection induced fault activation.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.6 no.3
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• pp.126-134
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• 2001

Several angular sandstone fragments (about 7 cm in longest diameter) occur in two piston cores, obtained from the submarine trough in the northeastern part of Korea Strait. The origin of the sandstone fragments and the paleoenvironment of trough sediment could be suggested from sedimentary facies analysis of cores and identification of ostracod within sandstone fragments. Echo characteristics around two core sites in submarine trough represent the prolonged bottom echoes with diffuse or no subbottom reflectors. The cores consist of a lower bioturbated mud and an upper gravelly sand sediments with sandstone/shell fragments. The bioturbated mud sediments show low water contents (27-44%) and high shear strength (19.2->37 kPa) compared with those of Holocene sediments (60-219% and 1.0-2.7 kPa, respectively) in the inner shelf and continental slope. However, clay contents (48-56%) of the bioturbated mud sediments are similar to those of fluviatile Holocene sediments in the inner shelf. The mean grain size of gravelly sand sediments ranges from 2.3 to 3.0 ${\phi}$ and shows coarsening upward with sandstone/shell fragments. The Holocene palimpsest in the continental shelf are composed of muddy sand sediments or sandy mud sediments (mean grain size: 4.6-7.6 ${\phi}$). Those suggest that two core sediments might be formed from Paleofluvial and paleocoastal deposits during sea-level lowstand. However, sandstone fragments mainly consist of quartz grains and bioclasts, with carbonate matrix, hollow pore, and glauconite. Two extinct ostracod species, Normanicythere sp. and Kotoracythere sp., are recovered in the sand-stone fragments of core EP-7, and they continued to exist from late Pliocene to early Pleistocene in cold water environment of this area. Thus, the sandstone fragments are interpreted to be formed at the paleocoastal environment derived from the Plio-Pleistocene outcrops exposed around the submarine trough during the LGM (Last Glacial Maximum) period.

• Economic and Environmental Geology
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• v.36 no.4
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• pp.285-293
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• 2003

Tailings of Dukum mine in the vadose and saturated zone were investigated to reveal the mobility of metal elements and the condition of mineralogical solubility according to redox environments throughout the geochemical analysis, thermodynamic modelling, and mineralogical study for solid-samples and water samples(vadose zone; distilled water: tailings=5 : 1 reacted, saturated zone; pore-water extracted). In the vadose zone, sulfide oxidation has generated low-pH(2.72∼6.91) condition and high concentration levels of S $O_4$$^{2-}$(561∼1430mg/L) and other metals(Zn : 0.12∼l57 mg/L, Pb : 0.06∼0.83 mg/L, Cd : 0.06∼l.35 mg/L). Jarosite$(KFe_3(SO_4)_2(OH)_6)$ and gypsum$(CaSO_4{\cdot}2H_2O$) were identified on XRD patterns and thermodynamics modelling. In the saturated zone, concentration of metal ions decreased because pH values were neutral(7.25∼8.10). But Fe and Mn susceptible to redox potential increased by low-pe values(7.40∼3.40) as the depth increased. Rhodochrosite$(MnCO_3)$ identified by XRD and thermodynamics modelling suggested that $Mn^{4+}$ or $Mn^{3+}$ was reduced to $Mn^{2+}$. Along pH conditions, concentrations of dissolved metal ions has been most abundant in vadose zone throughout borehole samples. It was observed that pH had more effect on metal solubilities than redox potential. How-ever, the release of co-precipitated heavy metals following the dissolution of Fe-Mn oxyhydroxides could be the mechanism by which reduced condition affected heavy metal solubility considering the decrease of pe as depth increased in tile saturated zone.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.7
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• pp.833-840
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• 2017

For wide application of perilla leaf, which has various healthy functions and can be easily cultured across Korea, the physicochemical and sensory properties of pan bread made with various amounts of squeezed perilla leaf juice (SPLJ) were analyzed. When dough characteristics were analyzed by using farinograph, consistency and dough development time were not significantly different between the control and bread dough made with various amounts of SPLJ, whereas dough stability time increased with increasing SPLJ amount. Expansion rate of dough decreased with increasing SPLJ amount. The volume, specific volume, and baking loss rate of pan bread made with various SPLJ amounts decreased with increasing SPLJ amount. Pan bread crumb colors became thickened and greenish with increasing SPLJ amount. For physical properties of pan bread made with various SPLJ amounts, springiness and cohesiveness decreased with increasing SPLJ amount, whereas brittleness, chewiness, and hardness increased with increasing SPLJ amount. In the sensory strength analysis, pore uniformity and soft texture decreased with increasing SPLJ amount, whereas crumb color (dark greenish), perilla leaf odor, perilla leaf taste, and chewing texture increased with increasing SPLJ amount. In the overall acceptance analysis, 1.5% SPLJ was the most preferred with a score of 7.10. However, statistical differences between 1.5% and 1.0% SPLJ were not detected at P<0.05. In the partial least squares analysis, consumers liked bread with a green crumb color, perilla leaf odor, perilla leaf taste, and soft and chewing texture. In conclusion, physicochemical properties of pan bread made with SPLJ were less desirable than those of the control; however, consumer acceptance of pan bread made with 1.5% SPLJ was shown the highest. Therefore, methods for increasing physicochemical properties of pan bread made with SPLJ need to be developed for wide application of perilla leaf.

• Horticultural Science & Technology
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• v.33 no.1
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• pp.70-82
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• 2015

This study was conducted to establish an efficient screening system to identify melon resistant to Fusarium oxysporum f. sp. melonis. F. oyxsporum f. sp. melonis GR was isolated from infected melon plants collected at Goryeong and identified as F. oxysporum f. sp. melonis based on morphological characteristics, molecular analyses, and host-specificity tests on cucurbits including melon, oriental melon, cucumber, and watermelon. In addition, the GR isolate was determined as race 1 based on resistance responses of melon differentials to the fungus. To select optimized medium for mass production of inoculum of F. oxysporum f. sp. melonis GR, six media were tested. The fungus produced the most spores (microconidia) in V8-juice broth. Resistance degrees to the GR isolate of 22 commercial melon cultivars and 6 rootstocks for melon plants were investigated. All tested rootstocks showed no symptoms of Fusarium wilt. Among the tested melon cultivars, only three cultivars were susceptible and the other cultivars displayed moderate to high resistance to the GR isolate. For further study, six melon cultivars (Redqueen, Summercool, Superseji, Asiapapaya, Eolukpapaya, and Asiahwanggeum) showing different degrees of resistance to the fungus were selected. The development of Fusarium wilt on the cultivars was tested according to several conditions such as plant growth stage, root wounding, dipping period of roots in spore suspension, inoculum concentration, and incubation temperature to develop the disease. On the basis of the test results, we suggest that an efficient screening method for melon plants resistant to F. oxysporum f. sp. melonis is to remove soil from roots of seven-day-old melon seedlings, to dip the seedlings without cutting in s pore s uspension of $3{\times}10^5conidia/mL$ for 30 min, to transplant the inoculated seedlings to plastic pots with horticulture nursery media, and then to cultivate the plants in a growth room at 25 to $28^{\circ}C$ for about 3 weeks with 12-hour light per day.