• Journal of the Mineralogical Society of Korea
• /
• v.21 no.2
• /
• pp.139-159
• /
• 2008

Geochemical analysis of the various kinds of water including observation borehole groundwater was carried out for the assessment of the hydrological safety of the underground oil storage cavern and the potentiality of mineralogical and microbiological clogging was estimated. Most of water samples belonged to $Ca-HCO_3$ and $Ca-HCO_3-SO_4$ types. There was no distinct chemical difference in the various kinds of water. All kinds of water are undersaturated with the calcite which is the major clogging mineral. Most water samples have low Fe and Mn concentrations. However, they are saturated or oversaturated with the iron-oxide/hydroxide minerals and have high dissolved oxygen contents which suggests the possibility of clogging by the iron-oxide/hydroxide minerals as a long-term aspect. Several water samples from the ground observation borehole also show the high saturation indices far the clay minerals, which can fill up the fractures, indicating the possibility of clogging by the clay minerals. Statistical analysis shows the degree of mineral precipitation or dissolution is mainly controlled by pH, Eh and DO of water samples. According to the microbial analysis, the aerobic microbes and slime forming bacteria are dominant in most water samples and anaerobic microbes including sulfate reducing bacteria are very low or not detected. Although the slime forming bacteria which are known as a main microbial cause of the clogging is lower than $10^5\;CFUs/mL$ in all water samples, because the slime forming bacteria are dominant microbe in several observation boreholes, the clogging can be caused by it as a long-term aspect. In addition, the possibility of clogging can be increased if the microbial effect is combined with the mineralogical effect such as iron oxide/hydroxide minerals for the possibility of clogging. Therefore, the systematic and long-term program for the assessment of clogging is required for the safe operation of underground oil storage cavern.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.12 no.1
• /
• pp.529-536
• /
• 2011

In this study, we confirmed that the SWRO(Sea Water Reverse Osmosis) production water has more hard corrosiveness than the tap water by fundamental experiment. According to the result, the target of this study was aimed at developing maintenance and anti-corrosion method. In the early stages of the research, batch tests using mild steel coupons and electrochemical experiments were applied to compare the corrosiveness between SWRO production water and the tap water. After then, two corrosion control methods for SWRO production water were applied. Liquid lime($Ca(OH)_2$) and Carbon Dioxide($CO_2$) were inserted and compared with the combination of liquid lime with phosphate corrosion inhibitor and carbon dioxide. The water qualities were evaluated through LSI(Langelier Saturation Index) and proper injection ratio was deduced by the result. Since then, simulated loop system test were performed to evaluate anti-corrosion effect depending on corrosion inhibitors. Subsequently, carbon steel pipes equipped at the loop system were detached for SEM, EDX and XRD analysis to acquire quantitative and qualitative data of the major corrosion products inside the pipes. In conclusion, the controled groups with anti-corrosion techniques applied were effective by appearing 97.4% and 90.9% of improvements in both case of liquid lime and the liquid lime with a phosphate corrosion Inhibitor. furthermore, major components of scale were iron oxides, on the other hand, protective effect of film formation by calcium carbonate($CaCO_3$) could be confirmed.

• Tuberculosis and Respiratory Diseases
• /
• v.53 no.6
• /
• pp.612-618
• /
• 2002

Background : Bronchoscopy is an important diagnostic and a therapeutic tool in chest medicine. However, most patients feel that a bronchoscopy is an unpleasant procedure, and it is important to sedate the patients appropriately, particularly where repetitive examinations are required. Midazolam is a sedative drug with amnestic qualities and a rapid 2 hour half-life. This study have attempted to determine the safety, appropriate dosage, and the effect of midazolam premedication in patients who underwent a bronchoscopy. Methods : One hundred and eighty consecutive patients undergoing bronchoscopy were enrolled in this study. The patients received a midzolam doses of 0.03 mg/kg, 0.06 mg/kg, or a placebo. An additional dose of lidocaine, the total number of coughs, and the duration of the procedures were recorded with monitoring the the blood pressure, heart rate, and oxygen saturation. The level of satisfaction was assessed by the patient, bronchoscopist, and the nurse. Results : The blood pressure, pulse rates, oxygen saturation, number of coughs, lidocaine dose, and procedure time in the 3 groups were similar. There was a trend for the midazolam 0.03 mg/kg group to satisfy bronchoscopists more than the other two groups. The nurses' acceptability was lower in the midazolam 0.06 mg/kg group than the other groups. The patients' acceptablity was greater in both the midazolam 0.03 mg/kg and 0.06 mg/kg groups than in the control group. Conclusion : Sedation with low doses of intravenous midazolam is a safe technique for fiberoptic bronchoscopy with a low morbidity and high acceptable to patients and bronchoscopists.

• The Journal of Engineering Geology
• /
• v.22 no.2
• /
• pp.145-155
• /
• 2012

The matric suction and volumetric water content of Jumunin standard sand with a relative density of 60% were measured using an Automated Soil-Water Characteristic Curve (SWCC) apparatus during both drying and wetting processes. The test time for the drying process was longer than that for the wetting process, because the flow of water is likely to be protected by air trapped in voids within the soils during the drying process. Based on the matric suction and volumetric water content, the SWCC was estimated using the model proposed by van Genuchten (1980). For the drying process, the unsaturated fitting parameters ${\alpha}$, n, and m were 0.399, 8.586, and 0.884, respectively; for the wetting process, the values were 0.548, 5.625, and 8.220, respectively. The hysteresis phenomenon occurred in the SWCCs, which means the SWCC of the drying process is not matched with the SWCC of the wetting process. Using these unsaturated parameters, we estimated the Suction Stress Characteristic Curve (SSCC), based on the relationship between suction stress and the effective degree of saturation. The suction stress showed a rapid decrease when the matric suction exceeds the Air Entry Value (AEV). Therefore, the effective stress of unsaturated soils is different from that of saturated soils when the matric suction exceeds the AEV. The suction stress of the drying process exceeds that of the wetting process for a given effective degree of saturation. The hysteresis phenomenon was also recognized in SSCCs. The hysteresis phenomenon of SSCCs arises from that of SWCCs, which is induced by the ink bottle effect and the contact angle effect. In the case of a sandy slope, the suction stress is positive and acts to enhance the slope stability as the water infiltrates the ground, but is negative when the suction stress exceeds the AEV. The results obtained for the wetting process should be applied in analyses of slope stability, because the process of water infiltration into ground is similar to the wetting process.

• The Korean Journal of Ceramics
• /
• v.6 no.2
• /
• pp.100-102
• /
• 2000

Co fine particles were dispersed in Au metal and $AlO_x$ amorphous matrices by vacuum evaporation and rf-sputtering, respectively, thus forming granular composite films having chemical compositions of $Co_{0.59}-Au_{0.41}$ and $Co_{0.52}/(AlO_x$)_{0.48}$. The films were annealed at 200~$500^{\circ}C$ to increase the size of the Co particles, from 30$\AA$ to 180$\AA$ in the Au matrix and 40$\AA$ to 180$\AA$ in the $AlO_x$ matrix, as revealed by X-ray diffraction analysis. The Co metal in as-deposited films have saturation magnetization equivalent to that of bulk Co, which is unchanged by the annealing, showing that the Co metal is not oxidized by the annealing. Magneto-optical Kerr rotation measured at $\lambda$=400-900nm for the $Co_{0.59}-Au_{0.41}$ film as deposited is larger than that calculated for the composition. The rotation increases as the film is annealed at $200^{\circ}C$ and $300^{\circ}C$, approaching to that of bulk Co. The Kerr rotation for the $Co_{0.52}-(AlO_x)_{0.48}$ film as deposited is smaller than that calculated for the composition based on Bruggeman effective medium theory. However, the rotation increases much, exceeding the rotation of the bulk Co as annealed at $300^{\circ}C$ and $400^{\circ}C$. As a possible origin of the marked magneto-optical enhancement a weak localization of light in granular structure is suggested.

• Journal of Fashion Business
• /
• v.13 no.6
• /
• pp.125-136
• /
• 2009

The main objective of this research was to understand the characteristics of complementary color scheme through the analysis of contemporary women's fashion color coordination as they appear in the 'Collections'. Data collection of 115 was done through review of 'pr$\hat{e}$t-$\grave{a}$-porter Collections' of four cities; Milan, London, New York, Paris. Statistical analysis of frequency and also qualitative interpretation of characteristics of complementary color harmony characteristics which appeared in four collections were completed. The main findings were as followed; (1) Only 115 complementary color schemes out of 4968 two color combinations appeared. Compared the comparative ratios of appearance frequency between the two color combination and the complementary color harmony, London showed the highest, and followed by New York, and Milan and Paris. (2)The combined color type of 'red+green' was the most frequently appeared, and followed by 'violet+yellow' and 'orange+blue'. For the type of tone harmony, the contrast tone showed the most, and followed by the similarity and identity. According to the type of complementary color combination, the type of tone harmony used differently. Some differences showed in the types of color harmony and tone harmony between collections. (3) The complementary color scheme which shown in four collections harmonized two opposite colors mainly through the strong tone contrast and this could cause tension along with interest in the image. The complementary colors intensified and brought out the attributes each other. More details, high contrast of two complementary colors of yellow and violet created a vibrant look especially when used at higher saturation. Sometimes, however, some tone variations of two hues neutralized the strong effect and sometimes enhanced each other. When they used in similarity tones or identity tones in light colors, the tension was reduced and became softened but still presented nice harmony. In the type of 'red+green' color harmony, the various color combinations were demonstrated, mostly through tone manipulation of green color. The similarity tone harmony, which used the most, could effect a better sense of harmony and present more sophisticated looks. When used in contrast tone harmony, some changes in its own color which have only one color of two the excessive intensity led a good harmony. The 'orange+blue' color harmony was shown the least and used three tone harmony almost the same ratio. In this color harmony, blue amplified its energy and brilliance of orange and seemed to work better when one color was at a lower intensity than the other. In harmony with a similarity and an identity tone, this color harmony produces a stable and calm image. (4) The complementary scheme appeared more frequently in the S/S collections than in A/W collections and showed some differences in the types of color harmony and tone harmony between seasons, however, no big differences between collections.

• Journal of the Korean Geotechnical Society
• /
• v.36 no.11
• /
• pp.149-156
• /
• 2020

Permeation grouting effectively enhances soil strength and decreases permeability of soil; however, the flow of grout is heavily affected by anisotropy of hydraulic conductivity in layers. Therefore, this study investigates the effect of permeability anisotropy on the effective radius of horizontal permeation grout using computational fluid dynamics (CFD). We modeled the horizontal permeation grout flow as a two-phase viscous fluid flow in porous media, and the model incorporated the chemical diffusion and the viscosity variation due to hardening. The numerical simulation reveals that the permeability anisotropy shapes the grout bulb to be elliptic and the dissolution-driven diffusion causes a gradual change in grout pore saturation at the edge of the grout bulb. For the grout pore saturations of 10%, 50% and 90%, the horizontal and vertical radii of grout bulb are estimated when the horizontal-to-vertical permeability ratio varies from 0.01 to 100, and the predictive model equations are suggested. This result contributes to more efficient design of injection strategy in formation layers with permeability anisotropy.

• Journal of the Institute of Electronics Engineers of Korea SP
• /
• v.47 no.6
• /
• pp.107-116
• /
• 2010

Smear is a phenomenon that occurs when an extremely strong light source appears in the imaging system with CCD sensor. It occurs due to the signal charge transfer of CCD and appears as bright lines of noise emanating vertically (or horizontally) from the light source. For still images, smear can be reduced by using a mechanical shutter or special drive methods, but these techniques cannot be applied to image sequences. In this paper, we propose a smear removal method that can be applied to imaging systems for not only still images but also image sequences. The proposed method uses the optical black region(OBR) which is a group of pixels located in the boundary of CCD imaging sensors. Although the OBR is not exposed to light, it contains smear information caused by the charge transport. First, noise and the smear signal in the OBR is separated, and noise is removed to correctly estimate smear effect. Then, corrected OBR signal is uniformly subtracted to eliminate smear effect. Also, if saturation is occurred, the current pixel is substituted by weighted summation of neighboring pixels to improve the visual degradation. Experimental results show that the proposed algorithm outperforms the conventional methods.

• Korean Journal of Materials Research
• /
• v.30 no.6
• /
• pp.292-300
• /
• 2020

In this study, the effect of tempering on the stretch-flangeability is investigated in 980 MPa grade dual-phase steel consisting of ferrite and martensite phases. During tempering at 300 ℃, the strength of ferrite increases due to the pinning of dislocations by carbon atoms released from martensite, while martensite is softened as a consequence of a reduction in its carbon super-saturation. This strength variation results in a considerable increase in yield strength of the steel, without loss of tensile strength. The hole expansion test shows that steel tempered for 20 min (T20 steel) exhibits a higher hole expansion ratio than that of steel without tempering (T0 steel). In T0 steel, severe plastic localization in ferrite causes easy pore formation at the ferrite-martensite interface and subsequent brittle crack propagation through the highly deformed ferrite area during hole expansion testing; this propagation is mainly attributed to the large difference in hardness between ferrite and martensite. When the difference in hardness is not so large (T20 steel), on the other hand, tempered martensite can be considerably deformed together with ferrite, thereby delaying pore formation and hindering crack propagation by crack blunting. Eventually, these different deformation and fracture behaviors contribute to the superior stretch-flangeability of T20 steel.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.25 no.2
• /
• pp.240-248
• /
• 1996

To clarify the potentiality of sea cucumbers as dietary food, the effects of those glycoprotein on dietary proteins and physicochemical properties of those proteins were studied. Crude glycoprotein was efficiently extracted using 20mM sodium phosphate beffer(pH 7.0) and by salting out with 80% ammoniym sulfate saturation. The fractions obtained through the DEAE-cellulose ion exchange chromatography was identified as glycoprotein by Schiff's reagent and SDS polyacrylanide gel electro-phoresis. The yields of each glycoprotein from the three kinds of sea cucumbers were 0.814(red), 0.184(blue) and 0.232(black) and the molecular weights of the glycoproteins subunits were ranged from 20,000 dalton(blue and black) to 29,000 dalton(red), respectively. The electrophoretic patterns of the glycoprotein isolates were similar to each other and any significant difference in amino acid pattern was observed. Predominant arnino scids were Asx(aspartic acid and asparagine) and Glx(glutamic acid and glutamine) ; in contrast, histidine and methionine were below 2% as compared to total amino acids. water holding capacities of the glycoprotein isolates from red, blue and black cucumbers were equally 100% and emulsion activities ranged from 53% to 64%. In addition the emulsion stabilities were 7.04, 1.37 and 2.44, respectively. In vitro digestibility of some proteins(casein, SPI and squid) was decreased as increasing the level of the freeze dried sea cucumber powder and glycoprotein isolates. But squid protein was not affected.