• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2000.05a
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• pp.33-36
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• 2000

The purpose of this study investigated underground oil storage(USTs) and Landfill using the envi-cone penetrometer system. The electrical resistivity sensor, pH sensor, ORP sensor, and thermometer are installed in envi-cone penetrometer system. This envi-cone penetrometer system provides a continuous profile of measurements, and it is rapid, repeatable, reliable and cost effective for investigation of contaminated ground.

• Electronics and Telecommunications Trends
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• v.18 no.6 s.84
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• pp.49-58
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• 2003

현재 UWB 기술은 무선통신을 비롯하여, 투과용 이미징 시스템, 차량용 및 지하 탐사용 레이더 등에 이르기까지 다양한 응용분야에 적용되고 있다. 이러한 다양한 분야에서 사용되는 UWB 기기들이 만족시켜야 할 기술적 조건들은 저마다 다를 수 있는데, 현재로서는 미국만이 자국의 기술기준을 마련한 상태이다. 따라서 본 고에서는 미국의 UWB 기술규제 동향을 바탕으로 유럽과 일본의 기술기준 제정동향과 함께 향후 제정될 국내의 기술기준의 방향에 대하여 함께 살펴보았다.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.8
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• pp.56-63
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• 2010

This work proposes a 12b 100MS/s 0.13um CMOS pipeline ADC for battery-powered mobile video applications such as DVB-Handheld (DVB-H), DVB-Terrestrial (DVB-T), Satellite DMB (SDMB), and Terrestrial DMB (TDMB) requiring high resolution, low power, and small size at high speed. The proposed ADC employs a three-step pipeline architecture to optimize power consumption and chip area at the target resolution and sampling rate. A single shared and switched op-amp for two MDACs removes a memory effect and a switching time delay, resulting in a fast signal settling. A two-step reference selection scheme for the last-stage 6b FLASH ADC reduces power consumption and chip area by 50%. The prototype ADC in a 0.13um 1P7M CMOS technology demonstrates a measured DNL and INL within 0.40LSB and 1.79LSB, respectively. The ADC shows a maximum SNDR of 60.0dB and a maximum SFDR of 72.4dB at 100MS/s, respectively. The ADC with an active die area of 0.92 $mm^2$ consumes 24mW at 1.0V and 100MS/s. The FOM, power/($f_s{\times}2^{ENOB}$), of 0.29pJ/conv. is the lowest of ever reported 12b 100MS/s ADCs.

• The Korean Journal of Ecology
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• v.28 no.2
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• pp.93-98
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• 2005

The effects of the presence of a submerged plant, Zizania latifolia, on physico-chemical characteristics, including Eh, pH, and concentrations of nitrogen and phosphorus in the sediments were studied under pot culture condition. It was shown that Eh value at reduced layer of the sediments was higher in the planted pots than in the non-planted. It was also revealed that $NH_4^+-N$ concentration of the sediments in the planted pots was lower than that of the non-planted, which might be due to the uptake by the plants. In contrast, $NO_3^--N$ concentration in the sediment increased in the presence of the plants compared to the non-planted, which might be attributed to oxygen released from the roots to the reduced layer. The concentration of organic phosphorus in the sediments was much higher than that of NAIP at the beginning of the planting experiment. However, at the end of the experiment, it was reversed; NAIP concentration was much higher than that of organic phosphorus, possibly indicating the transformation of organic phosphorus to NAIP during the experimental period. Both concentrations of $NH_4^+-N$ and $PO_4^{3-}-P$ in the overlying and percolated water were lower in the planted pots than in the non-planted. The concentration of $NO_3^--N$ in the percolated water, however, was higher in the planted pots than in the non-planted. The data was discussed with regard to the potential effects of a submerged plant on dynamics of phosphorus and nitrogen in the rhizosphere of the sediment.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.10
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• pp.1567-1575
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• 2013

Anti-inflammatory effects of sulfur-fed duck extract on colitis induced by 2.5% dextran sulfate sodium (DSS) were examined in male Balb/c mice. Animals were divided into eight groups: normal (0.1 mL of PBS without 2.5% DSS), control (0.1 mL of PBS with 2.5% DSS), SD-H (3 mL/kg of high sulfur-fed duck extract), SD-L (1 mL/kg of low sulfur-fed duck extract), GD-H (3 mL/kg of high general duck extract), GD-L (1 mL/kg of low general duck extract), GC-H (3 mL/kg of high general chicken extract), and GC-L (1 mL/kg of low general chicken extract). Mice were fed PBS or six different doses of extracts (sulfur-fed duck, general duck, and chicken), once daily for 14 days. Colitis was induced from day 7 to 14 via the administration of 2.5% DSS in drinking water. The colon length was significantly shortened in mice compared to the control group. The administration of SD-H, SD-L, and GD-L increased colon length and decreased histological colon injury from DSS-induced colitis. However, chicken extracts did not recover any clinical sign of the colitis. SD-L significantly suppressed not only the concentrations of IL-$1{\beta}$, IL-6, TNF-${\alpha}$, IL-17A, and IL-12 in serum but also the mRNA expressions of IL-6, TNF-${\alpha}$, iNOS and COX-2 in DSS-treated colon tissues (P<0.05). The administration of SD-H suppressed the concentrations of IL-6 in serum and the mRNA expressions of IL-6, iNOS, and COX-2 in colon tissues. Administration of GD-L suppressed the concentrations of IL-6, TNF-${\alpha}$, and IL-17A in serum and the mRNA expressions of IL-6, iNOS, and COX-2 in colon tissues. The inhibitory effects of sulfur-fed duck extracts were effective at a dose of 1 mL/kg. Our results indicate that sulfur-fed duck extracts may possess anti-inflammatory effects on DSS-induced colitis mice.

• Journal of Conservation Science
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• v.35 no.5
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• pp.480-493
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• 2019

In this study, the method for processing glue and glue-alum sizing from the dancheong ground treatment was evaluated with respect to weather resistance, and its effect on the conservation of dancheong was analyzed. Viscosity and pH of the glue and glue-alum specimen were measured and classified into three categories(none layer, glue layer, and glue-alum layer), which were further classified according to low concentration(four times for 2%) and high concentration(once for 10%). The base layer formation was subsequently classified into three categories based on pigment adoption, namely, Noerok(celadonite), Seokganju(terra rossa), and Jangdan(red lead). The completed specimen was subjected to a changing-environment experiment for evaluating weather resistance and observing the surface. Color variations were analyzed before and after the experiment. The results indicate that glue-alum sizing comprising 5% alum or 7% alum has strong acidity that can affect the life of dancheong, and the high level of 7% alum makes it difficult to create a solid coating layer. After ultraviolet irradiation, the specimen with 7% alum changes its color to yellow. Furthermore, after moisture absorption and drying, cracks can be observed on the entire specimen surface that corroborate the physical change. Additionally, gas-based corrosion causes marginal surface changes. Hence, the formation of a stable coating layer can be achieved by incorporating a low concentration glue solution that is almost neutral, and the application of glue-alum sizing having 2% concentration can aid in the conservation of dancheong.

• Journal of the Korea Concrete Institute
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• v.20 no.6
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• pp.713-719
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• 2008

Various types of coatings have been developed for use as reinforcement in concrete and to resist chloride environment. The most commonly used coatings are inhibited and sealed cement slurry coating, cement polymer compositing coating and epoxy coating. Cement slurry offers passive protection, epoxy coating offers barrier protection whereas polymer coating offers both passive protection and barrier protection. Moreover, damage during handling of the steel may result in disbondment of the epoxy coating, which would increase the risk of localized corrosion. In the present study, inhibiting technique was used to increase the calcium hydroxide content at the interface up to 20%. Calcium hydroxide provides a high buffering capacity that resists a local fall in pH and thus maintains the alkaline environment necessary to prevent chloride corrosion. This study examines the use of a calcium hydroxide coating on the steel surface to enhance the pH buffering capacity of steel-concrete interface. Finally, the chloride threshold level (CTL) of polymer inhibitive coating calcium hydroxide is evaluated.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.4
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• pp.663-668
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• 2000

To develop natural intermediate flavoring substances, optimal processing conditions and qualities for two stage enzyme hydrolysate (TSEH) from low-utilized small longfinned squid were investigated. The optimal conditions for TSEH method were found as digestion with Alcalase (0.2% w/w-sample, pH 8.0) at 55$^{\circ}C$ 3 hours at the 1st stage and with Neutrase (exo-peptidase, 0.2% w/w-sample, pH 6.0) at 45$^{\circ}C$ for 2~3 hours at the 2nd stage. Among the method of water extract, autolytic extract and various kinds yields, transparency and organoleptic taste. From the results of chemical experiments and sensory evaluation, longfinned squid TSEH is flavorable as the natural intermediate taste-active substances for fisheries products such as soup base, squid-taste pasty and snacks.

• Korean Journal of Food Science and Technology
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• v.26 no.3
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• pp.324-330
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• 1994

This study was conducted to examine the effects of the kinds and the levels of salted and fermented seafoods, shrimp and juice of anchovy, on the properties of kimchi during fermentation. There were no significant differences in pH and contents of total acid, reducing sugar, and organic acid examined except lactic acid contents among the kimchi samples at the same fermentation period. Until four days of fermentation, kimchi containing higher level of salted and fermented anchovy juice tended to have greater number of total microorganisms and of Leuconostoc genus microorganisms than the other kimchi samples. Sensory characteristics were not significantly different among the samples at the same fermentation period. significant decrease in pH and in reducing sugar content, and increase in total acid content were noticed in all the kimchi samples during fermentation. This was more marked in kimchi samples containg salted and fermented seafoods. Contents of malic and succinic acids decreased while those of actic and acetic acids increased with longer fermentation. There were significant changes in the numbers of microorganisms during fermentation. Carbonic mouthfeel, salty taste, sour taste and staled flay or of all the kimchi samples increased while firmness and crispness decreased with extended fermentation.

• Journal of Life Science
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• v.14 no.4
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• pp.702-707
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• 2004

In native-polyacrylamide gel electrophoresis of Pangasius polyuranodon, the lactate dehydrogenase (EC 1.1.1.27, LDH) $A_4$, $A_3$B, $A_2$$B_2$,$AB_3$ and $B_4$ isozymes were expressed in various tissues. The LDH $A_4$ and liver-specific $C_4$ isozymes were expressed in the tissues of Hypostomus Plecostomus. The bands of LDH in skeletal muscle, heart and eye tissues were not detected while one band was detected in kidney and liver, and four bands were detected in brain. The detected one band in liver was identified as alcohol dehydrogenase and an anodal band of skeletal muscle was identified as nothing dehydrogenase. The LDH in skeletal muscle, heart and eye might function as pyruvate reductase. The degree of inhibitions of LDH in skeletal muscle and heart of P. polyuranodon by 10 mM pyruvate were measured 57.6% and 73.8%, respectively. However, those of LDH in tissues of H. plecostomus were measured 52.7-61.8% so tissue specificity did not appear. Therefore, H. ple-costomus might be more acclimated to hypoxic environment by anaerobic metabolism of LDH iso-zymes than P. polyuranodon.